11cb0ef41Sopenharmony_ci<!DOCTYPE html> 21cb0ef41Sopenharmony_ci<html lang="en"> 31cb0ef41Sopenharmony_ci<head> 41cb0ef41Sopenharmony_ci <meta charset="utf-8"> 51cb0ef41Sopenharmony_ci <meta name="viewport" content="width=device-width"> 61cb0ef41Sopenharmony_ci <meta name="nodejs.org:node-version" content="v18.20.1"> 71cb0ef41Sopenharmony_ci <title>Web Streams API | Node.js v18.20.1 Documentation</title> 81cb0ef41Sopenharmony_ci <link rel="stylesheet" href="https://fonts.googleapis.com/css?family=Lato:400,700,400italic&display=fallback"> 91cb0ef41Sopenharmony_ci <link rel="stylesheet" href="assets/style.css"> 101cb0ef41Sopenharmony_ci <link rel="stylesheet" href="assets/hljs.css"> 111cb0ef41Sopenharmony_ci <link rel="canonical" href="https://nodejs.org/api/webstreams.html"> 121cb0ef41Sopenharmony_ci <script async defer src="assets/api.js" type="text/javascript"></script> 131cb0ef41Sopenharmony_ci <style>@media(max-width:358px){.with-17-chars>.js-flavor-selector{float:none;margin:0 0 1em auto;}}@media(max-width:654px){.with-54-chars>.js-flavor-selector{float:none;margin:0 0 1em auto;}}@media(max-width:334px){.with-14-chars>.js-flavor-selector{float:none;margin:0 0 1em auto;}}@media(max-width:678px){.with-57-chars>.js-flavor-selector{float:none;margin:0 0 1em auto;}}@media(max-width:622px){.with-50-chars>.js-flavor-selector{float:none;margin:0 0 1em auto;}}@media(max-width:638px){.with-52-chars>.js-flavor-selector{float:none;margin:0 0 1em auto;}}</style> 141cb0ef41Sopenharmony_ci</head> 151cb0ef41Sopenharmony_ci<body class="alt apidoc" id="api-section-webstreams"> 161cb0ef41Sopenharmony_ci <div id="content" class="clearfix"> 171cb0ef41Sopenharmony_ci <div id="column2" class="interior"> 181cb0ef41Sopenharmony_ci <div id="intro" class="interior"> 191cb0ef41Sopenharmony_ci <a href="/" title="Go back to the home page"> 201cb0ef41Sopenharmony_ci Node.js 211cb0ef41Sopenharmony_ci </a> 221cb0ef41Sopenharmony_ci </div> 231cb0ef41Sopenharmony_ci <ul> 241cb0ef41Sopenharmony_ci<li><a href="documentation.html" class="nav-documentation">About this documentation</a></li> 251cb0ef41Sopenharmony_ci<li><a href="synopsis.html" class="nav-synopsis">Usage and example</a></li> 261cb0ef41Sopenharmony_ci</ul> 271cb0ef41Sopenharmony_ci<hr class="line"> 281cb0ef41Sopenharmony_ci<ul> 291cb0ef41Sopenharmony_ci<li><a href="assert.html" class="nav-assert">Assertion testing</a></li> 301cb0ef41Sopenharmony_ci<li><a href="async_context.html" class="nav-async_context">Asynchronous context tracking</a></li> 311cb0ef41Sopenharmony_ci<li><a href="async_hooks.html" class="nav-async_hooks">Async hooks</a></li> 321cb0ef41Sopenharmony_ci<li><a href="buffer.html" class="nav-buffer">Buffer</a></li> 331cb0ef41Sopenharmony_ci<li><a href="addons.html" class="nav-addons">C++ addons</a></li> 341cb0ef41Sopenharmony_ci<li><a href="n-api.html" class="nav-n-api">C/C++ addons with Node-API</a></li> 351cb0ef41Sopenharmony_ci<li><a href="embedding.html" class="nav-embedding">C++ embedder API</a></li> 361cb0ef41Sopenharmony_ci<li><a href="child_process.html" class="nav-child_process">Child processes</a></li> 371cb0ef41Sopenharmony_ci<li><a href="cluster.html" class="nav-cluster">Cluster</a></li> 381cb0ef41Sopenharmony_ci<li><a href="cli.html" class="nav-cli">Command-line options</a></li> 391cb0ef41Sopenharmony_ci<li><a href="console.html" class="nav-console">Console</a></li> 401cb0ef41Sopenharmony_ci<li><a href="corepack.html" class="nav-corepack">Corepack</a></li> 411cb0ef41Sopenharmony_ci<li><a href="crypto.html" class="nav-crypto">Crypto</a></li> 421cb0ef41Sopenharmony_ci<li><a href="debugger.html" class="nav-debugger">Debugger</a></li> 431cb0ef41Sopenharmony_ci<li><a href="deprecations.html" class="nav-deprecations">Deprecated APIs</a></li> 441cb0ef41Sopenharmony_ci<li><a href="diagnostics_channel.html" class="nav-diagnostics_channel">Diagnostics Channel</a></li> 451cb0ef41Sopenharmony_ci<li><a href="dns.html" class="nav-dns">DNS</a></li> 461cb0ef41Sopenharmony_ci<li><a href="domain.html" class="nav-domain">Domain</a></li> 471cb0ef41Sopenharmony_ci<li><a href="errors.html" class="nav-errors">Errors</a></li> 481cb0ef41Sopenharmony_ci<li><a href="events.html" class="nav-events">Events</a></li> 491cb0ef41Sopenharmony_ci<li><a href="fs.html" class="nav-fs">File system</a></li> 501cb0ef41Sopenharmony_ci<li><a href="globals.html" class="nav-globals">Globals</a></li> 511cb0ef41Sopenharmony_ci<li><a href="http.html" class="nav-http">HTTP</a></li> 521cb0ef41Sopenharmony_ci<li><a href="http2.html" class="nav-http2">HTTP/2</a></li> 531cb0ef41Sopenharmony_ci<li><a href="https.html" class="nav-https">HTTPS</a></li> 541cb0ef41Sopenharmony_ci<li><a href="inspector.html" class="nav-inspector">Inspector</a></li> 551cb0ef41Sopenharmony_ci<li><a href="intl.html" class="nav-intl">Internationalization</a></li> 561cb0ef41Sopenharmony_ci<li><a href="modules.html" class="nav-modules">Modules: CommonJS modules</a></li> 571cb0ef41Sopenharmony_ci<li><a href="esm.html" class="nav-esm">Modules: ECMAScript modules</a></li> 581cb0ef41Sopenharmony_ci<li><a href="module.html" class="nav-module">Modules: <code>node:module</code> API</a></li> 591cb0ef41Sopenharmony_ci<li><a href="packages.html" class="nav-packages">Modules: Packages</a></li> 601cb0ef41Sopenharmony_ci<li><a href="net.html" class="nav-net">Net</a></li> 611cb0ef41Sopenharmony_ci<li><a href="os.html" class="nav-os">OS</a></li> 621cb0ef41Sopenharmony_ci<li><a href="path.html" class="nav-path">Path</a></li> 631cb0ef41Sopenharmony_ci<li><a href="perf_hooks.html" class="nav-perf_hooks">Performance hooks</a></li> 641cb0ef41Sopenharmony_ci<li><a href="permissions.html" class="nav-permissions">Permissions</a></li> 651cb0ef41Sopenharmony_ci<li><a href="process.html" class="nav-process">Process</a></li> 661cb0ef41Sopenharmony_ci<li><a href="punycode.html" class="nav-punycode">Punycode</a></li> 671cb0ef41Sopenharmony_ci<li><a href="querystring.html" class="nav-querystring">Query strings</a></li> 681cb0ef41Sopenharmony_ci<li><a href="readline.html" class="nav-readline">Readline</a></li> 691cb0ef41Sopenharmony_ci<li><a href="repl.html" class="nav-repl">REPL</a></li> 701cb0ef41Sopenharmony_ci<li><a href="report.html" class="nav-report">Report</a></li> 711cb0ef41Sopenharmony_ci<li><a href="single-executable-applications.html" class="nav-single-executable-applications">Single executable applications</a></li> 721cb0ef41Sopenharmony_ci<li><a href="stream.html" class="nav-stream">Stream</a></li> 731cb0ef41Sopenharmony_ci<li><a href="string_decoder.html" class="nav-string_decoder">String decoder</a></li> 741cb0ef41Sopenharmony_ci<li><a href="test.html" class="nav-test">Test runner</a></li> 751cb0ef41Sopenharmony_ci<li><a href="timers.html" class="nav-timers">Timers</a></li> 761cb0ef41Sopenharmony_ci<li><a href="tls.html" class="nav-tls">TLS/SSL</a></li> 771cb0ef41Sopenharmony_ci<li><a href="tracing.html" class="nav-tracing">Trace events</a></li> 781cb0ef41Sopenharmony_ci<li><a href="tty.html" class="nav-tty">TTY</a></li> 791cb0ef41Sopenharmony_ci<li><a href="dgram.html" class="nav-dgram">UDP/datagram</a></li> 801cb0ef41Sopenharmony_ci<li><a href="url.html" class="nav-url">URL</a></li> 811cb0ef41Sopenharmony_ci<li><a href="util.html" class="nav-util">Utilities</a></li> 821cb0ef41Sopenharmony_ci<li><a href="v8.html" class="nav-v8">V8</a></li> 831cb0ef41Sopenharmony_ci<li><a href="vm.html" class="nav-vm">VM</a></li> 841cb0ef41Sopenharmony_ci<li><a href="wasi.html" class="nav-wasi">WASI</a></li> 851cb0ef41Sopenharmony_ci<li><a href="webcrypto.html" class="nav-webcrypto">Web Crypto API</a></li> 861cb0ef41Sopenharmony_ci<li><a href="webstreams.html" class="nav-webstreams active">Web Streams API</a></li> 871cb0ef41Sopenharmony_ci<li><a href="worker_threads.html" class="nav-worker_threads">Worker threads</a></li> 881cb0ef41Sopenharmony_ci<li><a href="zlib.html" class="nav-zlib">Zlib</a></li> 891cb0ef41Sopenharmony_ci</ul> 901cb0ef41Sopenharmony_ci<hr class="line"> 911cb0ef41Sopenharmony_ci<ul> 921cb0ef41Sopenharmony_ci<li><a href="https://github.com/nodejs/node" class="nav-https-github-com-nodejs-node">Code repository and issue tracker</a></li> 931cb0ef41Sopenharmony_ci</ul> 941cb0ef41Sopenharmony_ci </div> 951cb0ef41Sopenharmony_ci 961cb0ef41Sopenharmony_ci <div id="column1" data-id="webstreams" class="interior"> 971cb0ef41Sopenharmony_ci <header class="header"> 981cb0ef41Sopenharmony_ci <div class="header-container"> 991cb0ef41Sopenharmony_ci <h1>Node.js v18.20.1 documentation</h1> 1001cb0ef41Sopenharmony_ci <button class="theme-toggle-btn" id="theme-toggle-btn" title="Toggle dark mode/light mode" aria-label="Toggle dark mode/light mode" hidden> 1011cb0ef41Sopenharmony_ci <svg xmlns="http://www.w3.org/2000/svg" class="icon dark-icon" height="24" width="24"> 1021cb0ef41Sopenharmony_ci <path fill="none" d="M0 0h24v24H0z" /> 1031cb0ef41Sopenharmony_ci <path d="M11.1 12.08c-2.33-4.51-.5-8.48.53-10.07C6.27 2.2 1.98 6.59 1.98 12c0 .14.02.28.02.42.62-.27 1.29-.42 2-.42 1.66 0 3.18.83 4.1 2.15A4.01 4.01 0 0111 18c0 1.52-.87 2.83-2.12 3.51.98.32 2.03.5 3.11.5 3.5 0 6.58-1.8 8.37-4.52-2.36.23-6.98-.97-9.26-5.41z"/> 1041cb0ef41Sopenharmony_ci <path d="M7 16h-.18C6.4 14.84 5.3 14 4 14c-1.66 0-3 1.34-3 3s1.34 3 3 3h3c1.1 0 2-.9 2-2s-.9-2-2-2z"/> 1051cb0ef41Sopenharmony_ci </svg> 1061cb0ef41Sopenharmony_ci <svg xmlns="http://www.w3.org/2000/svg" class="icon light-icon" height="24" width="24"> 1071cb0ef41Sopenharmony_ci <path d="M0 0h24v24H0z" fill="none" /> 1081cb0ef41Sopenharmony_ci <path d="M6.76 4.84l-1.8-1.79-1.41 1.41 1.79 1.79 1.42-1.41zM4 10.5H1v2h3v-2zm9-9.95h-2V3.5h2V.55zm7.45 3.91l-1.41-1.41-1.79 1.79 1.41 1.41 1.79-1.79zm-3.21 13.7l1.79 1.8 1.41-1.41-1.8-1.79-1.4 1.4zM20 10.5v2h3v-2h-3zm-8-5c-3.31 0-6 2.69-6 6s2.69 6 6 6 6-2.69 6-6-2.69-6-6-6zm-1 16.95h2V19.5h-2v2.95zm-7.45-3.91l1.41 1.41 1.79-1.8-1.41-1.41-1.79 1.8z"/> 1091cb0ef41Sopenharmony_ci </svg> 1101cb0ef41Sopenharmony_ci </button> 1111cb0ef41Sopenharmony_ci </div> 1121cb0ef41Sopenharmony_ci <div id="gtoc"> 1131cb0ef41Sopenharmony_ci <ul> 1141cb0ef41Sopenharmony_ci <li class="pinned-header">Node.js v18.20.1</li> 1151cb0ef41Sopenharmony_ci 1161cb0ef41Sopenharmony_ci <li class="picker-header"> 1171cb0ef41Sopenharmony_ci <a href="#"> 1181cb0ef41Sopenharmony_ci <span class="collapsed-arrow">►</span><span class="expanded-arrow">▼</span> 1191cb0ef41Sopenharmony_ci Table of contents 1201cb0ef41Sopenharmony_ci </a> 1211cb0ef41Sopenharmony_ci 1221cb0ef41Sopenharmony_ci <div class="picker"><div class="toc"><ul> 1231cb0ef41Sopenharmony_ci<li><span class="stability_1"><a href="#web-streams-api">Web Streams API</a></span> 1241cb0ef41Sopenharmony_ci<ul> 1251cb0ef41Sopenharmony_ci<li><a href="#overview">Overview</a> 1261cb0ef41Sopenharmony_ci<ul> 1271cb0ef41Sopenharmony_ci<li><a href="#example-readablestream">Example <code>ReadableStream</code></a></li> 1281cb0ef41Sopenharmony_ci</ul> 1291cb0ef41Sopenharmony_ci</li> 1301cb0ef41Sopenharmony_ci<li><a href="#api">API</a> 1311cb0ef41Sopenharmony_ci<ul> 1321cb0ef41Sopenharmony_ci<li><a href="#class-readablestream">Class: <code>ReadableStream</code></a> 1331cb0ef41Sopenharmony_ci<ul> 1341cb0ef41Sopenharmony_ci<li><a href="#new-readablestreamunderlyingsource--strategy"><code>new ReadableStream([underlyingSource [, strategy]])</code></a></li> 1351cb0ef41Sopenharmony_ci<li><a href="#readablestreamlocked"><code>readableStream.locked</code></a></li> 1361cb0ef41Sopenharmony_ci<li><a href="#readablestreamcancelreason"><code>readableStream.cancel([reason])</code></a></li> 1371cb0ef41Sopenharmony_ci<li><a href="#readablestreamgetreaderoptions"><code>readableStream.getReader([options])</code></a></li> 1381cb0ef41Sopenharmony_ci<li><a href="#readablestreampipethroughtransform-options"><code>readableStream.pipeThrough(transform[, options])</code></a></li> 1391cb0ef41Sopenharmony_ci<li><a href="#readablestreampipetodestination-options"><code>readableStream.pipeTo(destination[, options])</code></a></li> 1401cb0ef41Sopenharmony_ci<li><a href="#readablestreamtee"><code>readableStream.tee()</code></a></li> 1411cb0ef41Sopenharmony_ci<li><a href="#readablestreamvaluesoptions"><code>readableStream.values([options])</code></a></li> 1421cb0ef41Sopenharmony_ci<li><a href="#async-iteration">Async Iteration</a></li> 1431cb0ef41Sopenharmony_ci<li><a href="#transferring-with-postmessage">Transferring with <code>postMessage()</code></a></li> 1441cb0ef41Sopenharmony_ci</ul> 1451cb0ef41Sopenharmony_ci</li> 1461cb0ef41Sopenharmony_ci<li><a href="#class-readablestreamdefaultreader">Class: <code>ReadableStreamDefaultReader</code></a> 1471cb0ef41Sopenharmony_ci<ul> 1481cb0ef41Sopenharmony_ci<li><a href="#new-readablestreamdefaultreaderstream"><code>new ReadableStreamDefaultReader(stream)</code></a></li> 1491cb0ef41Sopenharmony_ci<li><a href="#readablestreamdefaultreadercancelreason"><code>readableStreamDefaultReader.cancel([reason])</code></a></li> 1501cb0ef41Sopenharmony_ci<li><a href="#readablestreamdefaultreaderclosed"><code>readableStreamDefaultReader.closed</code></a></li> 1511cb0ef41Sopenharmony_ci<li><a href="#readablestreamdefaultreaderread"><code>readableStreamDefaultReader.read()</code></a></li> 1521cb0ef41Sopenharmony_ci<li><a href="#readablestreamdefaultreaderreleaselock"><code>readableStreamDefaultReader.releaseLock()</code></a></li> 1531cb0ef41Sopenharmony_ci</ul> 1541cb0ef41Sopenharmony_ci</li> 1551cb0ef41Sopenharmony_ci<li><a href="#class-readablestreambyobreader">Class: <code>ReadableStreamBYOBReader</code></a> 1561cb0ef41Sopenharmony_ci<ul> 1571cb0ef41Sopenharmony_ci<li><a href="#new-readablestreambyobreaderstream"><code>new ReadableStreamBYOBReader(stream)</code></a></li> 1581cb0ef41Sopenharmony_ci<li><a href="#readablestreambyobreadercancelreason"><code>readableStreamBYOBReader.cancel([reason])</code></a></li> 1591cb0ef41Sopenharmony_ci<li><a href="#readablestreambyobreaderclosed"><code>readableStreamBYOBReader.closed</code></a></li> 1601cb0ef41Sopenharmony_ci<li><a href="#readablestreambyobreaderreadview"><code>readableStreamBYOBReader.read(view)</code></a></li> 1611cb0ef41Sopenharmony_ci<li><a href="#readablestreambyobreaderreleaselock"><code>readableStreamBYOBReader.releaseLock()</code></a></li> 1621cb0ef41Sopenharmony_ci</ul> 1631cb0ef41Sopenharmony_ci</li> 1641cb0ef41Sopenharmony_ci<li><a href="#class-readablestreamdefaultcontroller">Class: <code>ReadableStreamDefaultController</code></a> 1651cb0ef41Sopenharmony_ci<ul> 1661cb0ef41Sopenharmony_ci<li><a href="#readablestreamdefaultcontrollerclose"><code>readableStreamDefaultController.close()</code></a></li> 1671cb0ef41Sopenharmony_ci<li><a href="#readablestreamdefaultcontrollerdesiredsize"><code>readableStreamDefaultController.desiredSize</code></a></li> 1681cb0ef41Sopenharmony_ci<li><a href="#readablestreamdefaultcontrollerenqueuechunk"><code>readableStreamDefaultController.enqueue([chunk])</code></a></li> 1691cb0ef41Sopenharmony_ci<li><a href="#readablestreamdefaultcontrollererrorerror"><code>readableStreamDefaultController.error([error])</code></a></li> 1701cb0ef41Sopenharmony_ci</ul> 1711cb0ef41Sopenharmony_ci</li> 1721cb0ef41Sopenharmony_ci<li><a href="#class-readablebytestreamcontroller">Class: <code>ReadableByteStreamController</code></a> 1731cb0ef41Sopenharmony_ci<ul> 1741cb0ef41Sopenharmony_ci<li><a href="#readablebytestreamcontrollerbyobrequest"><code>readableByteStreamController.byobRequest</code></a></li> 1751cb0ef41Sopenharmony_ci<li><a href="#readablebytestreamcontrollerclose"><code>readableByteStreamController.close()</code></a></li> 1761cb0ef41Sopenharmony_ci<li><a href="#readablebytestreamcontrollerdesiredsize"><code>readableByteStreamController.desiredSize</code></a></li> 1771cb0ef41Sopenharmony_ci<li><a href="#readablebytestreamcontrollerenqueuechunk"><code>readableByteStreamController.enqueue(chunk)</code></a></li> 1781cb0ef41Sopenharmony_ci<li><a href="#readablebytestreamcontrollererrorerror"><code>readableByteStreamController.error([error])</code></a></li> 1791cb0ef41Sopenharmony_ci</ul> 1801cb0ef41Sopenharmony_ci</li> 1811cb0ef41Sopenharmony_ci<li><a href="#class-readablestreambyobrequest">Class: <code>ReadableStreamBYOBRequest</code></a> 1821cb0ef41Sopenharmony_ci<ul> 1831cb0ef41Sopenharmony_ci<li><a href="#readablestreambyobrequestrespondbyteswritten"><code>readableStreamBYOBRequest.respond(bytesWritten)</code></a></li> 1841cb0ef41Sopenharmony_ci<li><a href="#readablestreambyobrequestrespondwithnewviewview"><code>readableStreamBYOBRequest.respondWithNewView(view)</code></a></li> 1851cb0ef41Sopenharmony_ci<li><a href="#readablestreambyobrequestview"><code>readableStreamBYOBRequest.view</code></a></li> 1861cb0ef41Sopenharmony_ci</ul> 1871cb0ef41Sopenharmony_ci</li> 1881cb0ef41Sopenharmony_ci<li><a href="#class-writablestream">Class: <code>WritableStream</code></a> 1891cb0ef41Sopenharmony_ci<ul> 1901cb0ef41Sopenharmony_ci<li><a href="#new-writablestreamunderlyingsink-strategy"><code>new WritableStream([underlyingSink[, strategy]])</code></a></li> 1911cb0ef41Sopenharmony_ci<li><a href="#writablestreamabortreason"><code>writableStream.abort([reason])</code></a></li> 1921cb0ef41Sopenharmony_ci<li><a href="#writablestreamclose"><code>writableStream.close()</code></a></li> 1931cb0ef41Sopenharmony_ci<li><a href="#writablestreamgetwriter"><code>writableStream.getWriter()</code></a></li> 1941cb0ef41Sopenharmony_ci<li><a href="#writablestreamlocked"><code>writableStream.locked</code></a></li> 1951cb0ef41Sopenharmony_ci<li><a href="#transferring-with-postmessage_1">Transferring with postMessage()</a></li> 1961cb0ef41Sopenharmony_ci</ul> 1971cb0ef41Sopenharmony_ci</li> 1981cb0ef41Sopenharmony_ci<li><a href="#class-writablestreamdefaultwriter">Class: <code>WritableStreamDefaultWriter</code></a> 1991cb0ef41Sopenharmony_ci<ul> 2001cb0ef41Sopenharmony_ci<li><a href="#new-writablestreamdefaultwriterstream"><code>new WritableStreamDefaultWriter(stream)</code></a></li> 2011cb0ef41Sopenharmony_ci<li><a href="#writablestreamdefaultwriterabortreason"><code>writableStreamDefaultWriter.abort([reason])</code></a></li> 2021cb0ef41Sopenharmony_ci<li><a href="#writablestreamdefaultwriterclose"><code>writableStreamDefaultWriter.close()</code></a></li> 2031cb0ef41Sopenharmony_ci<li><a href="#writablestreamdefaultwriterclosed"><code>writableStreamDefaultWriter.closed</code></a></li> 2041cb0ef41Sopenharmony_ci<li><a href="#writablestreamdefaultwriterdesiredsize"><code>writableStreamDefaultWriter.desiredSize</code></a></li> 2051cb0ef41Sopenharmony_ci<li><a href="#writablestreamdefaultwriterready"><code>writableStreamDefaultWriter.ready</code></a></li> 2061cb0ef41Sopenharmony_ci<li><a href="#writablestreamdefaultwriterreleaselock"><code>writableStreamDefaultWriter.releaseLock()</code></a></li> 2071cb0ef41Sopenharmony_ci<li><a href="#writablestreamdefaultwriterwritechunk"><code>writableStreamDefaultWriter.write([chunk])</code></a></li> 2081cb0ef41Sopenharmony_ci</ul> 2091cb0ef41Sopenharmony_ci</li> 2101cb0ef41Sopenharmony_ci<li><a href="#class-writablestreamdefaultcontroller">Class: <code>WritableStreamDefaultController</code></a> 2111cb0ef41Sopenharmony_ci<ul> 2121cb0ef41Sopenharmony_ci<li><a href="#writablestreamdefaultcontrollererrorerror"><code>writableStreamDefaultController.error([error])</code></a></li> 2131cb0ef41Sopenharmony_ci<li><a href="#writablestreamdefaultcontrollersignal"><code>writableStreamDefaultController.signal</code></a></li> 2141cb0ef41Sopenharmony_ci</ul> 2151cb0ef41Sopenharmony_ci</li> 2161cb0ef41Sopenharmony_ci<li><a href="#class-transformstream">Class: <code>TransformStream</code></a> 2171cb0ef41Sopenharmony_ci<ul> 2181cb0ef41Sopenharmony_ci<li><a href="#new-transformstreamtransformer-writablestrategy-readablestrategy"><code>new TransformStream([transformer[, writableStrategy[, readableStrategy]]])</code></a></li> 2191cb0ef41Sopenharmony_ci<li><a href="#transformstreamreadable"><code>transformStream.readable</code></a></li> 2201cb0ef41Sopenharmony_ci<li><a href="#transformstreamwritable"><code>transformStream.writable</code></a></li> 2211cb0ef41Sopenharmony_ci<li><a href="#transferring-with-postmessage_2">Transferring with postMessage()</a></li> 2221cb0ef41Sopenharmony_ci</ul> 2231cb0ef41Sopenharmony_ci</li> 2241cb0ef41Sopenharmony_ci<li><a href="#class-transformstreamdefaultcontroller">Class: <code>TransformStreamDefaultController</code></a> 2251cb0ef41Sopenharmony_ci<ul> 2261cb0ef41Sopenharmony_ci<li><a href="#transformstreamdefaultcontrollerdesiredsize"><code>transformStreamDefaultController.desiredSize</code></a></li> 2271cb0ef41Sopenharmony_ci<li><a href="#transformstreamdefaultcontrollerenqueuechunk"><code>transformStreamDefaultController.enqueue([chunk])</code></a></li> 2281cb0ef41Sopenharmony_ci<li><a href="#transformstreamdefaultcontrollererrorreason"><code>transformStreamDefaultController.error([reason])</code></a></li> 2291cb0ef41Sopenharmony_ci<li><a href="#transformstreamdefaultcontrollerterminate"><code>transformStreamDefaultController.terminate()</code></a></li> 2301cb0ef41Sopenharmony_ci</ul> 2311cb0ef41Sopenharmony_ci</li> 2321cb0ef41Sopenharmony_ci<li><a href="#class-bytelengthqueuingstrategy">Class: <code>ByteLengthQueuingStrategy</code></a> 2331cb0ef41Sopenharmony_ci<ul> 2341cb0ef41Sopenharmony_ci<li><a href="#new-bytelengthqueuingstrategyinit"><code>new ByteLengthQueuingStrategy(init)</code></a></li> 2351cb0ef41Sopenharmony_ci<li><a href="#bytelengthqueuingstrategyhighwatermark"><code>byteLengthQueuingStrategy.highWaterMark</code></a></li> 2361cb0ef41Sopenharmony_ci<li><a href="#bytelengthqueuingstrategysize"><code>byteLengthQueuingStrategy.size</code></a></li> 2371cb0ef41Sopenharmony_ci</ul> 2381cb0ef41Sopenharmony_ci</li> 2391cb0ef41Sopenharmony_ci<li><a href="#class-countqueuingstrategy">Class: <code>CountQueuingStrategy</code></a> 2401cb0ef41Sopenharmony_ci<ul> 2411cb0ef41Sopenharmony_ci<li><a href="#new-countqueuingstrategyinit"><code>new CountQueuingStrategy(init)</code></a></li> 2421cb0ef41Sopenharmony_ci<li><a href="#countqueuingstrategyhighwatermark"><code>countQueuingStrategy.highWaterMark</code></a></li> 2431cb0ef41Sopenharmony_ci<li><a href="#countqueuingstrategysize"><code>countQueuingStrategy.size</code></a></li> 2441cb0ef41Sopenharmony_ci</ul> 2451cb0ef41Sopenharmony_ci</li> 2461cb0ef41Sopenharmony_ci<li><a href="#class-textencoderstream">Class: <code>TextEncoderStream</code></a> 2471cb0ef41Sopenharmony_ci<ul> 2481cb0ef41Sopenharmony_ci<li><a href="#new-textencoderstream"><code>new TextEncoderStream()</code></a></li> 2491cb0ef41Sopenharmony_ci<li><a href="#textencoderstreamencoding"><code>textEncoderStream.encoding</code></a></li> 2501cb0ef41Sopenharmony_ci<li><a href="#textencoderstreamreadable"><code>textEncoderStream.readable</code></a></li> 2511cb0ef41Sopenharmony_ci<li><a href="#textencoderstreamwritable"><code>textEncoderStream.writable</code></a></li> 2521cb0ef41Sopenharmony_ci</ul> 2531cb0ef41Sopenharmony_ci</li> 2541cb0ef41Sopenharmony_ci<li><a href="#class-textdecoderstream">Class: <code>TextDecoderStream</code></a> 2551cb0ef41Sopenharmony_ci<ul> 2561cb0ef41Sopenharmony_ci<li><a href="#new-textdecoderstreamencoding-options"><code>new TextDecoderStream([encoding[, options]])</code></a></li> 2571cb0ef41Sopenharmony_ci<li><a href="#textdecoderstreamencoding"><code>textDecoderStream.encoding</code></a></li> 2581cb0ef41Sopenharmony_ci<li><a href="#textdecoderstreamfatal"><code>textDecoderStream.fatal</code></a></li> 2591cb0ef41Sopenharmony_ci<li><a href="#textdecoderstreamignorebom"><code>textDecoderStream.ignoreBOM</code></a></li> 2601cb0ef41Sopenharmony_ci<li><a href="#textdecoderstreamreadable"><code>textDecoderStream.readable</code></a></li> 2611cb0ef41Sopenharmony_ci<li><a href="#textdecoderstreamwritable"><code>textDecoderStream.writable</code></a></li> 2621cb0ef41Sopenharmony_ci</ul> 2631cb0ef41Sopenharmony_ci</li> 2641cb0ef41Sopenharmony_ci<li><a href="#class-compressionstream">Class: <code>CompressionStream</code></a> 2651cb0ef41Sopenharmony_ci<ul> 2661cb0ef41Sopenharmony_ci<li><a href="#new-compressionstreamformat"><code>new CompressionStream(format)</code></a></li> 2671cb0ef41Sopenharmony_ci<li><a href="#compressionstreamreadable"><code>compressionStream.readable</code></a></li> 2681cb0ef41Sopenharmony_ci<li><a href="#compressionstreamwritable"><code>compressionStream.writable</code></a></li> 2691cb0ef41Sopenharmony_ci</ul> 2701cb0ef41Sopenharmony_ci</li> 2711cb0ef41Sopenharmony_ci<li><a href="#class-decompressionstream">Class: <code>DecompressionStream</code></a> 2721cb0ef41Sopenharmony_ci<ul> 2731cb0ef41Sopenharmony_ci<li><a href="#new-decompressionstreamformat"><code>new DecompressionStream(format)</code></a></li> 2741cb0ef41Sopenharmony_ci<li><a href="#decompressionstreamreadable"><code>decompressionStream.readable</code></a></li> 2751cb0ef41Sopenharmony_ci<li><a href="#decompressionstreamwritable"><code>decompressionStream.writable</code></a></li> 2761cb0ef41Sopenharmony_ci</ul> 2771cb0ef41Sopenharmony_ci</li> 2781cb0ef41Sopenharmony_ci<li><a href="#utility-consumers">Utility Consumers</a> 2791cb0ef41Sopenharmony_ci<ul> 2801cb0ef41Sopenharmony_ci<li><a href="#streamconsumersarraybufferstream"><code>streamConsumers.arrayBuffer(stream)</code></a></li> 2811cb0ef41Sopenharmony_ci<li><a href="#streamconsumersblobstream"><code>streamConsumers.blob(stream)</code></a></li> 2821cb0ef41Sopenharmony_ci<li><a href="#streamconsumersbufferstream"><code>streamConsumers.buffer(stream)</code></a></li> 2831cb0ef41Sopenharmony_ci<li><a href="#streamconsumersjsonstream"><code>streamConsumers.json(stream)</code></a></li> 2841cb0ef41Sopenharmony_ci<li><a href="#streamconsumerstextstream"><code>streamConsumers.text(stream)</code></a></li> 2851cb0ef41Sopenharmony_ci</ul> 2861cb0ef41Sopenharmony_ci</li> 2871cb0ef41Sopenharmony_ci</ul> 2881cb0ef41Sopenharmony_ci</li> 2891cb0ef41Sopenharmony_ci</ul> 2901cb0ef41Sopenharmony_ci</li> 2911cb0ef41Sopenharmony_ci</ul></div></div> 2921cb0ef41Sopenharmony_ci </li> 2931cb0ef41Sopenharmony_ci 2941cb0ef41Sopenharmony_ci 2951cb0ef41Sopenharmony_ci <li class="picker-header"> 2961cb0ef41Sopenharmony_ci <a href="#"> 2971cb0ef41Sopenharmony_ci <span class="collapsed-arrow">►</span><span class="expanded-arrow">▼</span> 2981cb0ef41Sopenharmony_ci Index 2991cb0ef41Sopenharmony_ci </a> 3001cb0ef41Sopenharmony_ci 3011cb0ef41Sopenharmony_ci <div class="picker"><ul> 3021cb0ef41Sopenharmony_ci<li><a href="documentation.html" class="nav-documentation">About this documentation</a></li> 3031cb0ef41Sopenharmony_ci<li><a href="synopsis.html" class="nav-synopsis">Usage and example</a></li> 3041cb0ef41Sopenharmony_ci 3051cb0ef41Sopenharmony_ci <li> 3061cb0ef41Sopenharmony_ci <a href="index.html">Index</a> 3071cb0ef41Sopenharmony_ci </li> 3081cb0ef41Sopenharmony_ci </ul> 3091cb0ef41Sopenharmony_ci 3101cb0ef41Sopenharmony_ci<hr class="line"> 3111cb0ef41Sopenharmony_ci<ul> 3121cb0ef41Sopenharmony_ci<li><a href="assert.html" class="nav-assert">Assertion testing</a></li> 3131cb0ef41Sopenharmony_ci<li><a href="async_context.html" class="nav-async_context">Asynchronous context tracking</a></li> 3141cb0ef41Sopenharmony_ci<li><a href="async_hooks.html" class="nav-async_hooks">Async hooks</a></li> 3151cb0ef41Sopenharmony_ci<li><a href="buffer.html" class="nav-buffer">Buffer</a></li> 3161cb0ef41Sopenharmony_ci<li><a href="addons.html" class="nav-addons">C++ addons</a></li> 3171cb0ef41Sopenharmony_ci<li><a href="n-api.html" class="nav-n-api">C/C++ addons with Node-API</a></li> 3181cb0ef41Sopenharmony_ci<li><a href="embedding.html" class="nav-embedding">C++ embedder API</a></li> 3191cb0ef41Sopenharmony_ci<li><a href="child_process.html" class="nav-child_process">Child processes</a></li> 3201cb0ef41Sopenharmony_ci<li><a href="cluster.html" class="nav-cluster">Cluster</a></li> 3211cb0ef41Sopenharmony_ci<li><a href="cli.html" class="nav-cli">Command-line options</a></li> 3221cb0ef41Sopenharmony_ci<li><a href="console.html" class="nav-console">Console</a></li> 3231cb0ef41Sopenharmony_ci<li><a href="corepack.html" class="nav-corepack">Corepack</a></li> 3241cb0ef41Sopenharmony_ci<li><a href="crypto.html" class="nav-crypto">Crypto</a></li> 3251cb0ef41Sopenharmony_ci<li><a href="debugger.html" class="nav-debugger">Debugger</a></li> 3261cb0ef41Sopenharmony_ci<li><a href="deprecations.html" class="nav-deprecations">Deprecated APIs</a></li> 3271cb0ef41Sopenharmony_ci<li><a href="diagnostics_channel.html" class="nav-diagnostics_channel">Diagnostics Channel</a></li> 3281cb0ef41Sopenharmony_ci<li><a href="dns.html" class="nav-dns">DNS</a></li> 3291cb0ef41Sopenharmony_ci<li><a href="domain.html" class="nav-domain">Domain</a></li> 3301cb0ef41Sopenharmony_ci<li><a href="errors.html" class="nav-errors">Errors</a></li> 3311cb0ef41Sopenharmony_ci<li><a href="events.html" class="nav-events">Events</a></li> 3321cb0ef41Sopenharmony_ci<li><a href="fs.html" class="nav-fs">File system</a></li> 3331cb0ef41Sopenharmony_ci<li><a href="globals.html" class="nav-globals">Globals</a></li> 3341cb0ef41Sopenharmony_ci<li><a href="http.html" class="nav-http">HTTP</a></li> 3351cb0ef41Sopenharmony_ci<li><a href="http2.html" class="nav-http2">HTTP/2</a></li> 3361cb0ef41Sopenharmony_ci<li><a href="https.html" class="nav-https">HTTPS</a></li> 3371cb0ef41Sopenharmony_ci<li><a href="inspector.html" class="nav-inspector">Inspector</a></li> 3381cb0ef41Sopenharmony_ci<li><a href="intl.html" class="nav-intl">Internationalization</a></li> 3391cb0ef41Sopenharmony_ci<li><a href="modules.html" class="nav-modules">Modules: CommonJS modules</a></li> 3401cb0ef41Sopenharmony_ci<li><a href="esm.html" class="nav-esm">Modules: ECMAScript modules</a></li> 3411cb0ef41Sopenharmony_ci<li><a href="module.html" class="nav-module">Modules: <code>node:module</code> API</a></li> 3421cb0ef41Sopenharmony_ci<li><a href="packages.html" class="nav-packages">Modules: Packages</a></li> 3431cb0ef41Sopenharmony_ci<li><a href="net.html" class="nav-net">Net</a></li> 3441cb0ef41Sopenharmony_ci<li><a href="os.html" class="nav-os">OS</a></li> 3451cb0ef41Sopenharmony_ci<li><a href="path.html" class="nav-path">Path</a></li> 3461cb0ef41Sopenharmony_ci<li><a href="perf_hooks.html" class="nav-perf_hooks">Performance hooks</a></li> 3471cb0ef41Sopenharmony_ci<li><a href="permissions.html" class="nav-permissions">Permissions</a></li> 3481cb0ef41Sopenharmony_ci<li><a href="process.html" class="nav-process">Process</a></li> 3491cb0ef41Sopenharmony_ci<li><a href="punycode.html" class="nav-punycode">Punycode</a></li> 3501cb0ef41Sopenharmony_ci<li><a href="querystring.html" class="nav-querystring">Query strings</a></li> 3511cb0ef41Sopenharmony_ci<li><a href="readline.html" class="nav-readline">Readline</a></li> 3521cb0ef41Sopenharmony_ci<li><a href="repl.html" class="nav-repl">REPL</a></li> 3531cb0ef41Sopenharmony_ci<li><a href="report.html" class="nav-report">Report</a></li> 3541cb0ef41Sopenharmony_ci<li><a href="single-executable-applications.html" class="nav-single-executable-applications">Single executable applications</a></li> 3551cb0ef41Sopenharmony_ci<li><a href="stream.html" class="nav-stream">Stream</a></li> 3561cb0ef41Sopenharmony_ci<li><a href="string_decoder.html" class="nav-string_decoder">String decoder</a></li> 3571cb0ef41Sopenharmony_ci<li><a href="test.html" class="nav-test">Test runner</a></li> 3581cb0ef41Sopenharmony_ci<li><a href="timers.html" class="nav-timers">Timers</a></li> 3591cb0ef41Sopenharmony_ci<li><a href="tls.html" class="nav-tls">TLS/SSL</a></li> 3601cb0ef41Sopenharmony_ci<li><a href="tracing.html" class="nav-tracing">Trace events</a></li> 3611cb0ef41Sopenharmony_ci<li><a href="tty.html" class="nav-tty">TTY</a></li> 3621cb0ef41Sopenharmony_ci<li><a href="dgram.html" class="nav-dgram">UDP/datagram</a></li> 3631cb0ef41Sopenharmony_ci<li><a href="url.html" class="nav-url">URL</a></li> 3641cb0ef41Sopenharmony_ci<li><a href="util.html" class="nav-util">Utilities</a></li> 3651cb0ef41Sopenharmony_ci<li><a href="v8.html" class="nav-v8">V8</a></li> 3661cb0ef41Sopenharmony_ci<li><a href="vm.html" class="nav-vm">VM</a></li> 3671cb0ef41Sopenharmony_ci<li><a href="wasi.html" class="nav-wasi">WASI</a></li> 3681cb0ef41Sopenharmony_ci<li><a href="webcrypto.html" class="nav-webcrypto">Web Crypto API</a></li> 3691cb0ef41Sopenharmony_ci<li><a href="webstreams.html" class="nav-webstreams active">Web Streams API</a></li> 3701cb0ef41Sopenharmony_ci<li><a href="worker_threads.html" class="nav-worker_threads">Worker threads</a></li> 3711cb0ef41Sopenharmony_ci<li><a href="zlib.html" class="nav-zlib">Zlib</a></li> 3721cb0ef41Sopenharmony_ci</ul> 3731cb0ef41Sopenharmony_ci<hr class="line"> 3741cb0ef41Sopenharmony_ci<ul> 3751cb0ef41Sopenharmony_ci<li><a href="https://github.com/nodejs/node" class="nav-https-github-com-nodejs-node">Code repository and issue tracker</a></li> 3761cb0ef41Sopenharmony_ci</ul></div> 3771cb0ef41Sopenharmony_ci </li> 3781cb0ef41Sopenharmony_ci 3791cb0ef41Sopenharmony_ci 3801cb0ef41Sopenharmony_ci <li class="picker-header"> 3811cb0ef41Sopenharmony_ci <a href="#"> 3821cb0ef41Sopenharmony_ci <span class="collapsed-arrow">►</span><span class="expanded-arrow">▼</span> 3831cb0ef41Sopenharmony_ci Other versions 3841cb0ef41Sopenharmony_ci </a> 3851cb0ef41Sopenharmony_ci <div class="picker"><ol id="alt-docs"><li><a href="https://nodejs.org/docs/latest-v21.x/api/webstreams.html">21.x</a></li> 3861cb0ef41Sopenharmony_ci<li><a href="https://nodejs.org/docs/latest-v20.x/api/webstreams.html">20.x <b>LTS</b></a></li> 3871cb0ef41Sopenharmony_ci<li><a href="https://nodejs.org/docs/latest-v19.x/api/webstreams.html">19.x</a></li> 3881cb0ef41Sopenharmony_ci<li><a href="https://nodejs.org/docs/latest-v18.x/api/webstreams.html">18.x <b>LTS</b></a></li> 3891cb0ef41Sopenharmony_ci<li><a href="https://nodejs.org/docs/latest-v17.x/api/webstreams.html">17.x</a></li> 3901cb0ef41Sopenharmony_ci<li><a href="https://nodejs.org/docs/latest-v16.x/api/webstreams.html">16.x</a></li></ol></div> 3911cb0ef41Sopenharmony_ci </li> 3921cb0ef41Sopenharmony_ci 3931cb0ef41Sopenharmony_ci <li class="picker-header"> 3941cb0ef41Sopenharmony_ci <a href="#"> 3951cb0ef41Sopenharmony_ci <span class="collapsed-arrow">►</span><span class="expanded-arrow">▼</span> 3961cb0ef41Sopenharmony_ci Options 3971cb0ef41Sopenharmony_ci </a> 3981cb0ef41Sopenharmony_ci 3991cb0ef41Sopenharmony_ci <div class="picker"> 4001cb0ef41Sopenharmony_ci <ul> 4011cb0ef41Sopenharmony_ci <li> 4021cb0ef41Sopenharmony_ci <a href="all.html">View on single page</a> 4031cb0ef41Sopenharmony_ci </li> 4041cb0ef41Sopenharmony_ci <li> 4051cb0ef41Sopenharmony_ci <a href="webstreams.json">View as JSON</a> 4061cb0ef41Sopenharmony_ci </li> 4071cb0ef41Sopenharmony_ci <li class="edit_on_github"><a href="https://github.com/nodejs/node/edit/main/doc/api/webstreams.md">Edit on GitHub</a></li> 4081cb0ef41Sopenharmony_ci </ul> 4091cb0ef41Sopenharmony_ci </div> 4101cb0ef41Sopenharmony_ci </li> 4111cb0ef41Sopenharmony_ci </ul> 4121cb0ef41Sopenharmony_ci </div> 4131cb0ef41Sopenharmony_ci <hr> 4141cb0ef41Sopenharmony_ci </header> 4151cb0ef41Sopenharmony_ci 4161cb0ef41Sopenharmony_ci <details id="toc" open><summary>Table of contents</summary><ul> 4171cb0ef41Sopenharmony_ci<li><span class="stability_1"><a href="#web-streams-api">Web Streams API</a></span> 4181cb0ef41Sopenharmony_ci<ul> 4191cb0ef41Sopenharmony_ci<li><a href="#overview">Overview</a> 4201cb0ef41Sopenharmony_ci<ul> 4211cb0ef41Sopenharmony_ci<li><a href="#example-readablestream">Example <code>ReadableStream</code></a></li> 4221cb0ef41Sopenharmony_ci</ul> 4231cb0ef41Sopenharmony_ci</li> 4241cb0ef41Sopenharmony_ci<li><a href="#api">API</a> 4251cb0ef41Sopenharmony_ci<ul> 4261cb0ef41Sopenharmony_ci<li><a href="#class-readablestream">Class: <code>ReadableStream</code></a> 4271cb0ef41Sopenharmony_ci<ul> 4281cb0ef41Sopenharmony_ci<li><a href="#new-readablestreamunderlyingsource--strategy"><code>new ReadableStream([underlyingSource [, strategy]])</code></a></li> 4291cb0ef41Sopenharmony_ci<li><a href="#readablestreamlocked"><code>readableStream.locked</code></a></li> 4301cb0ef41Sopenharmony_ci<li><a href="#readablestreamcancelreason"><code>readableStream.cancel([reason])</code></a></li> 4311cb0ef41Sopenharmony_ci<li><a href="#readablestreamgetreaderoptions"><code>readableStream.getReader([options])</code></a></li> 4321cb0ef41Sopenharmony_ci<li><a href="#readablestreampipethroughtransform-options"><code>readableStream.pipeThrough(transform[, options])</code></a></li> 4331cb0ef41Sopenharmony_ci<li><a href="#readablestreampipetodestination-options"><code>readableStream.pipeTo(destination[, options])</code></a></li> 4341cb0ef41Sopenharmony_ci<li><a href="#readablestreamtee"><code>readableStream.tee()</code></a></li> 4351cb0ef41Sopenharmony_ci<li><a href="#readablestreamvaluesoptions"><code>readableStream.values([options])</code></a></li> 4361cb0ef41Sopenharmony_ci<li><a href="#async-iteration">Async Iteration</a></li> 4371cb0ef41Sopenharmony_ci<li><a href="#transferring-with-postmessage">Transferring with <code>postMessage()</code></a></li> 4381cb0ef41Sopenharmony_ci</ul> 4391cb0ef41Sopenharmony_ci</li> 4401cb0ef41Sopenharmony_ci<li><a href="#class-readablestreamdefaultreader">Class: <code>ReadableStreamDefaultReader</code></a> 4411cb0ef41Sopenharmony_ci<ul> 4421cb0ef41Sopenharmony_ci<li><a href="#new-readablestreamdefaultreaderstream"><code>new ReadableStreamDefaultReader(stream)</code></a></li> 4431cb0ef41Sopenharmony_ci<li><a href="#readablestreamdefaultreadercancelreason"><code>readableStreamDefaultReader.cancel([reason])</code></a></li> 4441cb0ef41Sopenharmony_ci<li><a href="#readablestreamdefaultreaderclosed"><code>readableStreamDefaultReader.closed</code></a></li> 4451cb0ef41Sopenharmony_ci<li><a href="#readablestreamdefaultreaderread"><code>readableStreamDefaultReader.read()</code></a></li> 4461cb0ef41Sopenharmony_ci<li><a href="#readablestreamdefaultreaderreleaselock"><code>readableStreamDefaultReader.releaseLock()</code></a></li> 4471cb0ef41Sopenharmony_ci</ul> 4481cb0ef41Sopenharmony_ci</li> 4491cb0ef41Sopenharmony_ci<li><a href="#class-readablestreambyobreader">Class: <code>ReadableStreamBYOBReader</code></a> 4501cb0ef41Sopenharmony_ci<ul> 4511cb0ef41Sopenharmony_ci<li><a href="#new-readablestreambyobreaderstream"><code>new ReadableStreamBYOBReader(stream)</code></a></li> 4521cb0ef41Sopenharmony_ci<li><a href="#readablestreambyobreadercancelreason"><code>readableStreamBYOBReader.cancel([reason])</code></a></li> 4531cb0ef41Sopenharmony_ci<li><a href="#readablestreambyobreaderclosed"><code>readableStreamBYOBReader.closed</code></a></li> 4541cb0ef41Sopenharmony_ci<li><a href="#readablestreambyobreaderreadview"><code>readableStreamBYOBReader.read(view)</code></a></li> 4551cb0ef41Sopenharmony_ci<li><a href="#readablestreambyobreaderreleaselock"><code>readableStreamBYOBReader.releaseLock()</code></a></li> 4561cb0ef41Sopenharmony_ci</ul> 4571cb0ef41Sopenharmony_ci</li> 4581cb0ef41Sopenharmony_ci<li><a href="#class-readablestreamdefaultcontroller">Class: <code>ReadableStreamDefaultController</code></a> 4591cb0ef41Sopenharmony_ci<ul> 4601cb0ef41Sopenharmony_ci<li><a href="#readablestreamdefaultcontrollerclose"><code>readableStreamDefaultController.close()</code></a></li> 4611cb0ef41Sopenharmony_ci<li><a href="#readablestreamdefaultcontrollerdesiredsize"><code>readableStreamDefaultController.desiredSize</code></a></li> 4621cb0ef41Sopenharmony_ci<li><a href="#readablestreamdefaultcontrollerenqueuechunk"><code>readableStreamDefaultController.enqueue([chunk])</code></a></li> 4631cb0ef41Sopenharmony_ci<li><a href="#readablestreamdefaultcontrollererrorerror"><code>readableStreamDefaultController.error([error])</code></a></li> 4641cb0ef41Sopenharmony_ci</ul> 4651cb0ef41Sopenharmony_ci</li> 4661cb0ef41Sopenharmony_ci<li><a href="#class-readablebytestreamcontroller">Class: <code>ReadableByteStreamController</code></a> 4671cb0ef41Sopenharmony_ci<ul> 4681cb0ef41Sopenharmony_ci<li><a href="#readablebytestreamcontrollerbyobrequest"><code>readableByteStreamController.byobRequest</code></a></li> 4691cb0ef41Sopenharmony_ci<li><a href="#readablebytestreamcontrollerclose"><code>readableByteStreamController.close()</code></a></li> 4701cb0ef41Sopenharmony_ci<li><a href="#readablebytestreamcontrollerdesiredsize"><code>readableByteStreamController.desiredSize</code></a></li> 4711cb0ef41Sopenharmony_ci<li><a href="#readablebytestreamcontrollerenqueuechunk"><code>readableByteStreamController.enqueue(chunk)</code></a></li> 4721cb0ef41Sopenharmony_ci<li><a href="#readablebytestreamcontrollererrorerror"><code>readableByteStreamController.error([error])</code></a></li> 4731cb0ef41Sopenharmony_ci</ul> 4741cb0ef41Sopenharmony_ci</li> 4751cb0ef41Sopenharmony_ci<li><a href="#class-readablestreambyobrequest">Class: <code>ReadableStreamBYOBRequest</code></a> 4761cb0ef41Sopenharmony_ci<ul> 4771cb0ef41Sopenharmony_ci<li><a href="#readablestreambyobrequestrespondbyteswritten"><code>readableStreamBYOBRequest.respond(bytesWritten)</code></a></li> 4781cb0ef41Sopenharmony_ci<li><a href="#readablestreambyobrequestrespondwithnewviewview"><code>readableStreamBYOBRequest.respondWithNewView(view)</code></a></li> 4791cb0ef41Sopenharmony_ci<li><a href="#readablestreambyobrequestview"><code>readableStreamBYOBRequest.view</code></a></li> 4801cb0ef41Sopenharmony_ci</ul> 4811cb0ef41Sopenharmony_ci</li> 4821cb0ef41Sopenharmony_ci<li><a href="#class-writablestream">Class: <code>WritableStream</code></a> 4831cb0ef41Sopenharmony_ci<ul> 4841cb0ef41Sopenharmony_ci<li><a href="#new-writablestreamunderlyingsink-strategy"><code>new WritableStream([underlyingSink[, strategy]])</code></a></li> 4851cb0ef41Sopenharmony_ci<li><a href="#writablestreamabortreason"><code>writableStream.abort([reason])</code></a></li> 4861cb0ef41Sopenharmony_ci<li><a href="#writablestreamclose"><code>writableStream.close()</code></a></li> 4871cb0ef41Sopenharmony_ci<li><a href="#writablestreamgetwriter"><code>writableStream.getWriter()</code></a></li> 4881cb0ef41Sopenharmony_ci<li><a href="#writablestreamlocked"><code>writableStream.locked</code></a></li> 4891cb0ef41Sopenharmony_ci<li><a href="#transferring-with-postmessage_1">Transferring with postMessage()</a></li> 4901cb0ef41Sopenharmony_ci</ul> 4911cb0ef41Sopenharmony_ci</li> 4921cb0ef41Sopenharmony_ci<li><a href="#class-writablestreamdefaultwriter">Class: <code>WritableStreamDefaultWriter</code></a> 4931cb0ef41Sopenharmony_ci<ul> 4941cb0ef41Sopenharmony_ci<li><a href="#new-writablestreamdefaultwriterstream"><code>new WritableStreamDefaultWriter(stream)</code></a></li> 4951cb0ef41Sopenharmony_ci<li><a href="#writablestreamdefaultwriterabortreason"><code>writableStreamDefaultWriter.abort([reason])</code></a></li> 4961cb0ef41Sopenharmony_ci<li><a href="#writablestreamdefaultwriterclose"><code>writableStreamDefaultWriter.close()</code></a></li> 4971cb0ef41Sopenharmony_ci<li><a href="#writablestreamdefaultwriterclosed"><code>writableStreamDefaultWriter.closed</code></a></li> 4981cb0ef41Sopenharmony_ci<li><a href="#writablestreamdefaultwriterdesiredsize"><code>writableStreamDefaultWriter.desiredSize</code></a></li> 4991cb0ef41Sopenharmony_ci<li><a href="#writablestreamdefaultwriterready"><code>writableStreamDefaultWriter.ready</code></a></li> 5001cb0ef41Sopenharmony_ci<li><a href="#writablestreamdefaultwriterreleaselock"><code>writableStreamDefaultWriter.releaseLock()</code></a></li> 5011cb0ef41Sopenharmony_ci<li><a href="#writablestreamdefaultwriterwritechunk"><code>writableStreamDefaultWriter.write([chunk])</code></a></li> 5021cb0ef41Sopenharmony_ci</ul> 5031cb0ef41Sopenharmony_ci</li> 5041cb0ef41Sopenharmony_ci<li><a href="#class-writablestreamdefaultcontroller">Class: <code>WritableStreamDefaultController</code></a> 5051cb0ef41Sopenharmony_ci<ul> 5061cb0ef41Sopenharmony_ci<li><a href="#writablestreamdefaultcontrollererrorerror"><code>writableStreamDefaultController.error([error])</code></a></li> 5071cb0ef41Sopenharmony_ci<li><a href="#writablestreamdefaultcontrollersignal"><code>writableStreamDefaultController.signal</code></a></li> 5081cb0ef41Sopenharmony_ci</ul> 5091cb0ef41Sopenharmony_ci</li> 5101cb0ef41Sopenharmony_ci<li><a href="#class-transformstream">Class: <code>TransformStream</code></a> 5111cb0ef41Sopenharmony_ci<ul> 5121cb0ef41Sopenharmony_ci<li><a href="#new-transformstreamtransformer-writablestrategy-readablestrategy"><code>new TransformStream([transformer[, writableStrategy[, readableStrategy]]])</code></a></li> 5131cb0ef41Sopenharmony_ci<li><a href="#transformstreamreadable"><code>transformStream.readable</code></a></li> 5141cb0ef41Sopenharmony_ci<li><a href="#transformstreamwritable"><code>transformStream.writable</code></a></li> 5151cb0ef41Sopenharmony_ci<li><a href="#transferring-with-postmessage_2">Transferring with postMessage()</a></li> 5161cb0ef41Sopenharmony_ci</ul> 5171cb0ef41Sopenharmony_ci</li> 5181cb0ef41Sopenharmony_ci<li><a href="#class-transformstreamdefaultcontroller">Class: <code>TransformStreamDefaultController</code></a> 5191cb0ef41Sopenharmony_ci<ul> 5201cb0ef41Sopenharmony_ci<li><a href="#transformstreamdefaultcontrollerdesiredsize"><code>transformStreamDefaultController.desiredSize</code></a></li> 5211cb0ef41Sopenharmony_ci<li><a href="#transformstreamdefaultcontrollerenqueuechunk"><code>transformStreamDefaultController.enqueue([chunk])</code></a></li> 5221cb0ef41Sopenharmony_ci<li><a href="#transformstreamdefaultcontrollererrorreason"><code>transformStreamDefaultController.error([reason])</code></a></li> 5231cb0ef41Sopenharmony_ci<li><a href="#transformstreamdefaultcontrollerterminate"><code>transformStreamDefaultController.terminate()</code></a></li> 5241cb0ef41Sopenharmony_ci</ul> 5251cb0ef41Sopenharmony_ci</li> 5261cb0ef41Sopenharmony_ci<li><a href="#class-bytelengthqueuingstrategy">Class: <code>ByteLengthQueuingStrategy</code></a> 5271cb0ef41Sopenharmony_ci<ul> 5281cb0ef41Sopenharmony_ci<li><a href="#new-bytelengthqueuingstrategyinit"><code>new ByteLengthQueuingStrategy(init)</code></a></li> 5291cb0ef41Sopenharmony_ci<li><a href="#bytelengthqueuingstrategyhighwatermark"><code>byteLengthQueuingStrategy.highWaterMark</code></a></li> 5301cb0ef41Sopenharmony_ci<li><a href="#bytelengthqueuingstrategysize"><code>byteLengthQueuingStrategy.size</code></a></li> 5311cb0ef41Sopenharmony_ci</ul> 5321cb0ef41Sopenharmony_ci</li> 5331cb0ef41Sopenharmony_ci<li><a href="#class-countqueuingstrategy">Class: <code>CountQueuingStrategy</code></a> 5341cb0ef41Sopenharmony_ci<ul> 5351cb0ef41Sopenharmony_ci<li><a href="#new-countqueuingstrategyinit"><code>new CountQueuingStrategy(init)</code></a></li> 5361cb0ef41Sopenharmony_ci<li><a href="#countqueuingstrategyhighwatermark"><code>countQueuingStrategy.highWaterMark</code></a></li> 5371cb0ef41Sopenharmony_ci<li><a href="#countqueuingstrategysize"><code>countQueuingStrategy.size</code></a></li> 5381cb0ef41Sopenharmony_ci</ul> 5391cb0ef41Sopenharmony_ci</li> 5401cb0ef41Sopenharmony_ci<li><a href="#class-textencoderstream">Class: <code>TextEncoderStream</code></a> 5411cb0ef41Sopenharmony_ci<ul> 5421cb0ef41Sopenharmony_ci<li><a href="#new-textencoderstream"><code>new TextEncoderStream()</code></a></li> 5431cb0ef41Sopenharmony_ci<li><a href="#textencoderstreamencoding"><code>textEncoderStream.encoding</code></a></li> 5441cb0ef41Sopenharmony_ci<li><a href="#textencoderstreamreadable"><code>textEncoderStream.readable</code></a></li> 5451cb0ef41Sopenharmony_ci<li><a href="#textencoderstreamwritable"><code>textEncoderStream.writable</code></a></li> 5461cb0ef41Sopenharmony_ci</ul> 5471cb0ef41Sopenharmony_ci</li> 5481cb0ef41Sopenharmony_ci<li><a href="#class-textdecoderstream">Class: <code>TextDecoderStream</code></a> 5491cb0ef41Sopenharmony_ci<ul> 5501cb0ef41Sopenharmony_ci<li><a href="#new-textdecoderstreamencoding-options"><code>new TextDecoderStream([encoding[, options]])</code></a></li> 5511cb0ef41Sopenharmony_ci<li><a href="#textdecoderstreamencoding"><code>textDecoderStream.encoding</code></a></li> 5521cb0ef41Sopenharmony_ci<li><a href="#textdecoderstreamfatal"><code>textDecoderStream.fatal</code></a></li> 5531cb0ef41Sopenharmony_ci<li><a href="#textdecoderstreamignorebom"><code>textDecoderStream.ignoreBOM</code></a></li> 5541cb0ef41Sopenharmony_ci<li><a href="#textdecoderstreamreadable"><code>textDecoderStream.readable</code></a></li> 5551cb0ef41Sopenharmony_ci<li><a href="#textdecoderstreamwritable"><code>textDecoderStream.writable</code></a></li> 5561cb0ef41Sopenharmony_ci</ul> 5571cb0ef41Sopenharmony_ci</li> 5581cb0ef41Sopenharmony_ci<li><a href="#class-compressionstream">Class: <code>CompressionStream</code></a> 5591cb0ef41Sopenharmony_ci<ul> 5601cb0ef41Sopenharmony_ci<li><a href="#new-compressionstreamformat"><code>new CompressionStream(format)</code></a></li> 5611cb0ef41Sopenharmony_ci<li><a href="#compressionstreamreadable"><code>compressionStream.readable</code></a></li> 5621cb0ef41Sopenharmony_ci<li><a href="#compressionstreamwritable"><code>compressionStream.writable</code></a></li> 5631cb0ef41Sopenharmony_ci</ul> 5641cb0ef41Sopenharmony_ci</li> 5651cb0ef41Sopenharmony_ci<li><a href="#class-decompressionstream">Class: <code>DecompressionStream</code></a> 5661cb0ef41Sopenharmony_ci<ul> 5671cb0ef41Sopenharmony_ci<li><a href="#new-decompressionstreamformat"><code>new DecompressionStream(format)</code></a></li> 5681cb0ef41Sopenharmony_ci<li><a href="#decompressionstreamreadable"><code>decompressionStream.readable</code></a></li> 5691cb0ef41Sopenharmony_ci<li><a href="#decompressionstreamwritable"><code>decompressionStream.writable</code></a></li> 5701cb0ef41Sopenharmony_ci</ul> 5711cb0ef41Sopenharmony_ci</li> 5721cb0ef41Sopenharmony_ci<li><a href="#utility-consumers">Utility Consumers</a> 5731cb0ef41Sopenharmony_ci<ul> 5741cb0ef41Sopenharmony_ci<li><a href="#streamconsumersarraybufferstream"><code>streamConsumers.arrayBuffer(stream)</code></a></li> 5751cb0ef41Sopenharmony_ci<li><a href="#streamconsumersblobstream"><code>streamConsumers.blob(stream)</code></a></li> 5761cb0ef41Sopenharmony_ci<li><a href="#streamconsumersbufferstream"><code>streamConsumers.buffer(stream)</code></a></li> 5771cb0ef41Sopenharmony_ci<li><a href="#streamconsumersjsonstream"><code>streamConsumers.json(stream)</code></a></li> 5781cb0ef41Sopenharmony_ci<li><a href="#streamconsumerstextstream"><code>streamConsumers.text(stream)</code></a></li> 5791cb0ef41Sopenharmony_ci</ul> 5801cb0ef41Sopenharmony_ci</li> 5811cb0ef41Sopenharmony_ci</ul> 5821cb0ef41Sopenharmony_ci</li> 5831cb0ef41Sopenharmony_ci</ul> 5841cb0ef41Sopenharmony_ci</li> 5851cb0ef41Sopenharmony_ci</ul></details> 5861cb0ef41Sopenharmony_ci 5871cb0ef41Sopenharmony_ci <div id="apicontent"> 5881cb0ef41Sopenharmony_ci <h2>Web Streams API<span><a class="mark" href="#web-streams-api" id="web-streams-api">#</a></span><a aria-hidden="true" class="legacy" id="webstreams_web_streams_api"></a></h2> 5891cb0ef41Sopenharmony_ci 5901cb0ef41Sopenharmony_ci<div class="api_metadata"> 5911cb0ef41Sopenharmony_ci<details class="changelog"><summary>History</summary> 5921cb0ef41Sopenharmony_ci<table> 5931cb0ef41Sopenharmony_ci<tbody><tr><th>Version</th><th>Changes</th></tr> 5941cb0ef41Sopenharmony_ci<tr><td>v18.0.0</td> 5951cb0ef41Sopenharmony_ci<td><p>Use of this API no longer emit a runtime warning.</p></td></tr> 5961cb0ef41Sopenharmony_ci<tr><td>v16.5.0</td> 5971cb0ef41Sopenharmony_ci<td><p><span>Added in: v16.5.0</span></p></td></tr> 5981cb0ef41Sopenharmony_ci</tbody></table> 5991cb0ef41Sopenharmony_ci</details> 6001cb0ef41Sopenharmony_ci</div> 6011cb0ef41Sopenharmony_ci<p></p><div class="api_stability api_stability_1"><a href="documentation.html#stability-index">Stability: 1</a> - Experimental.</div><p></p> 6021cb0ef41Sopenharmony_ci<p>An implementation of the <a href="https://streams.spec.whatwg.org/">WHATWG Streams Standard</a>.</p> 6031cb0ef41Sopenharmony_ci<section><h3>Overview<span><a class="mark" href="#overview" id="overview">#</a></span><a aria-hidden="true" class="legacy" id="webstreams_overview"></a></h3> 6041cb0ef41Sopenharmony_ci<p>The <a href="https://streams.spec.whatwg.org/">WHATWG Streams Standard</a> (or "web streams") defines an API for handling 6051cb0ef41Sopenharmony_cistreaming data. It is similar to the Node.js <a href="stream.html">Streams</a> API but emerged later 6061cb0ef41Sopenharmony_ciand has become the "standard" API for streaming data across many JavaScript 6071cb0ef41Sopenharmony_cienvironments.</p> 6081cb0ef41Sopenharmony_ci<p>There are three primary types of objects:</p> 6091cb0ef41Sopenharmony_ci<ul> 6101cb0ef41Sopenharmony_ci<li><code>ReadableStream</code> - Represents a source of streaming data.</li> 6111cb0ef41Sopenharmony_ci<li><code>WritableStream</code> - Represents a destination for streaming data.</li> 6121cb0ef41Sopenharmony_ci<li><code>TransformStream</code> - Represents an algorithm for transforming streaming data.</li> 6131cb0ef41Sopenharmony_ci</ul> 6141cb0ef41Sopenharmony_ci<h4>Example <code>ReadableStream</code><span><a class="mark" href="#example-readablestream" id="example-readablestream">#</a></span><a aria-hidden="true" class="legacy" id="webstreams_example_readablestream"></a></h4> 6151cb0ef41Sopenharmony_ci<p>This example creates a simple <code>ReadableStream</code> that pushes the current 6161cb0ef41Sopenharmony_ci<code>performance.now()</code> timestamp once every second forever. An async iterable 6171cb0ef41Sopenharmony_ciis used to read the data from the stream.</p> 6181cb0ef41Sopenharmony_ci 6191cb0ef41Sopenharmony_ci<pre class="with-17-chars"><input class="js-flavor-selector" type="checkbox" checked aria-label="Show modern ES modules syntax"><code class="language-js mjs"><span class="hljs-keyword">import</span> { 6201cb0ef41Sopenharmony_ci <span class="hljs-title class_">ReadableStream</span>, 6211cb0ef41Sopenharmony_ci} <span class="hljs-keyword">from</span> <span class="hljs-string">'node:stream/web'</span>; 6221cb0ef41Sopenharmony_ci 6231cb0ef41Sopenharmony_ci<span class="hljs-keyword">import</span> { 6241cb0ef41Sopenharmony_ci <span class="hljs-built_in">setInterval</span> <span class="hljs-keyword">as</span> every, 6251cb0ef41Sopenharmony_ci} <span class="hljs-keyword">from</span> <span class="hljs-string">'node:timers/promises'</span>; 6261cb0ef41Sopenharmony_ci 6271cb0ef41Sopenharmony_ci<span class="hljs-keyword">import</span> { 6281cb0ef41Sopenharmony_ci performance, 6291cb0ef41Sopenharmony_ci} <span class="hljs-keyword">from</span> <span class="hljs-string">'node:perf_hooks'</span>; 6301cb0ef41Sopenharmony_ci 6311cb0ef41Sopenharmony_ci<span class="hljs-keyword">const</span> <span class="hljs-variable constant_">SECOND</span> = <span class="hljs-number">1000</span>; 6321cb0ef41Sopenharmony_ci 6331cb0ef41Sopenharmony_ci<span class="hljs-keyword">const</span> stream = <span class="hljs-keyword">new</span> <span class="hljs-title class_">ReadableStream</span>({ 6341cb0ef41Sopenharmony_ci <span class="hljs-keyword">async</span> <span class="hljs-title function_">start</span>(<span class="hljs-params">controller</span>) { 6351cb0ef41Sopenharmony_ci <span class="hljs-keyword">for</span> <span class="hljs-keyword">await</span> (<span class="hljs-keyword">const</span> _ <span class="hljs-keyword">of</span> <span class="hljs-title function_">every</span>(<span class="hljs-variable constant_">SECOND</span>)) 6361cb0ef41Sopenharmony_ci controller.<span class="hljs-title function_">enqueue</span>(performance.<span class="hljs-title function_">now</span>()); 6371cb0ef41Sopenharmony_ci }, 6381cb0ef41Sopenharmony_ci}); 6391cb0ef41Sopenharmony_ci 6401cb0ef41Sopenharmony_ci<span class="hljs-keyword">for</span> <span class="hljs-keyword">await</span> (<span class="hljs-keyword">const</span> value <span class="hljs-keyword">of</span> stream) 6411cb0ef41Sopenharmony_ci <span class="hljs-variable language_">console</span>.<span class="hljs-title function_">log</span>(value);</code><code class="language-js cjs"><span class="hljs-keyword">const</span> { 6421cb0ef41Sopenharmony_ci <span class="hljs-title class_">ReadableStream</span>, 6431cb0ef41Sopenharmony_ci} = <span class="hljs-built_in">require</span>(<span class="hljs-string">'node:stream/web'</span>); 6441cb0ef41Sopenharmony_ci 6451cb0ef41Sopenharmony_ci<span class="hljs-keyword">const</span> { 6461cb0ef41Sopenharmony_ci <span class="hljs-attr">setInterval</span>: every, 6471cb0ef41Sopenharmony_ci} = <span class="hljs-built_in">require</span>(<span class="hljs-string">'node:timers/promises'</span>); 6481cb0ef41Sopenharmony_ci 6491cb0ef41Sopenharmony_ci<span class="hljs-keyword">const</span> { 6501cb0ef41Sopenharmony_ci performance, 6511cb0ef41Sopenharmony_ci} = <span class="hljs-built_in">require</span>(<span class="hljs-string">'node:perf_hooks'</span>); 6521cb0ef41Sopenharmony_ci 6531cb0ef41Sopenharmony_ci<span class="hljs-keyword">const</span> <span class="hljs-variable constant_">SECOND</span> = <span class="hljs-number">1000</span>; 6541cb0ef41Sopenharmony_ci 6551cb0ef41Sopenharmony_ci<span class="hljs-keyword">const</span> stream = <span class="hljs-keyword">new</span> <span class="hljs-title class_">ReadableStream</span>({ 6561cb0ef41Sopenharmony_ci <span class="hljs-keyword">async</span> <span class="hljs-title function_">start</span>(<span class="hljs-params">controller</span>) { 6571cb0ef41Sopenharmony_ci <span class="hljs-keyword">for</span> <span class="hljs-keyword">await</span> (<span class="hljs-keyword">const</span> _ <span class="hljs-keyword">of</span> <span class="hljs-title function_">every</span>(<span class="hljs-variable constant_">SECOND</span>)) 6581cb0ef41Sopenharmony_ci controller.<span class="hljs-title function_">enqueue</span>(performance.<span class="hljs-title function_">now</span>()); 6591cb0ef41Sopenharmony_ci }, 6601cb0ef41Sopenharmony_ci}); 6611cb0ef41Sopenharmony_ci 6621cb0ef41Sopenharmony_ci(<span class="hljs-keyword">async</span> () => { 6631cb0ef41Sopenharmony_ci <span class="hljs-keyword">for</span> <span class="hljs-keyword">await</span> (<span class="hljs-keyword">const</span> value <span class="hljs-keyword">of</span> stream) 6641cb0ef41Sopenharmony_ci <span class="hljs-variable language_">console</span>.<span class="hljs-title function_">log</span>(value); 6651cb0ef41Sopenharmony_ci})();</code><button class="copy-button">copy</button></pre> 6661cb0ef41Sopenharmony_ci</section><section><h3>API<span><a class="mark" href="#api" id="api">#</a></span><a aria-hidden="true" class="legacy" id="webstreams_api"></a></h3> 6671cb0ef41Sopenharmony_ci<h4>Class: <code>ReadableStream</code><span><a class="mark" href="#class-readablestream" id="class-readablestream">#</a></span><a aria-hidden="true" class="legacy" id="webstreams_class_readablestream"></a></h4> 6681cb0ef41Sopenharmony_ci<div class="api_metadata"> 6691cb0ef41Sopenharmony_ci<details class="changelog"><summary>History</summary> 6701cb0ef41Sopenharmony_ci<table> 6711cb0ef41Sopenharmony_ci<tbody><tr><th>Version</th><th>Changes</th></tr> 6721cb0ef41Sopenharmony_ci<tr><td>v18.0.0</td> 6731cb0ef41Sopenharmony_ci<td><p>This class is now exposed on the global object.</p></td></tr> 6741cb0ef41Sopenharmony_ci<tr><td>v16.5.0</td> 6751cb0ef41Sopenharmony_ci<td><p><span>Added in: v16.5.0</span></p></td></tr> 6761cb0ef41Sopenharmony_ci</tbody></table> 6771cb0ef41Sopenharmony_ci</details> 6781cb0ef41Sopenharmony_ci</div> 6791cb0ef41Sopenharmony_ci<h5><code>new ReadableStream([underlyingSource [, strategy]])</code><span><a class="mark" href="#new-readablestreamunderlyingsource--strategy" id="new-readablestreamunderlyingsource--strategy">#</a></span><a aria-hidden="true" class="legacy" id="webstreams_new_readablestream_underlyingsource_strategy"></a></h5> 6801cb0ef41Sopenharmony_ci<div class="api_metadata"> 6811cb0ef41Sopenharmony_ci<span>Added in: v16.5.0</span> 6821cb0ef41Sopenharmony_ci</div> 6831cb0ef41Sopenharmony_ci<!--lint disable maximum-line-length remark-lint--> 6841cb0ef41Sopenharmony_ci<ul> 6851cb0ef41Sopenharmony_ci<li><code>underlyingSource</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object" class="type"><Object></a> 6861cb0ef41Sopenharmony_ci<ul> 6871cb0ef41Sopenharmony_ci<li><code>start</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Function" class="type"><Function></a> A user-defined function that is invoked immediately when 6881cb0ef41Sopenharmony_cithe <code>ReadableStream</code> is created. 6891cb0ef41Sopenharmony_ci<ul> 6901cb0ef41Sopenharmony_ci<li><code>controller</code> <a href="webstreams.html#class-readablestreamdefaultcontroller" class="type"><ReadableStreamDefaultController></a> | <a href="webstreams.html#class-readablebytestreamcontroller" class="type"><ReadableByteStreamController></a></li> 6911cb0ef41Sopenharmony_ci<li>Returns: <code>undefined</code> or a promise fulfilled with <code>undefined</code>.</li> 6921cb0ef41Sopenharmony_ci</ul> 6931cb0ef41Sopenharmony_ci</li> 6941cb0ef41Sopenharmony_ci<li><code>pull</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Function" class="type"><Function></a> A user-defined function that is called repeatedly when the 6951cb0ef41Sopenharmony_ci<code>ReadableStream</code> internal queue is not full. The operation may be sync or 6961cb0ef41Sopenharmony_ciasync. If async, the function will not be called again until the previously 6971cb0ef41Sopenharmony_cireturned promise is fulfilled. 6981cb0ef41Sopenharmony_ci<ul> 6991cb0ef41Sopenharmony_ci<li><code>controller</code> <a href="webstreams.html#class-readablestreamdefaultcontroller" class="type"><ReadableStreamDefaultController></a> | <a href="webstreams.html#class-readablebytestreamcontroller" class="type"><ReadableByteStreamController></a></li> 7001cb0ef41Sopenharmony_ci<li>Returns: A promise fulfilled with <code>undefined</code>.</li> 7011cb0ef41Sopenharmony_ci</ul> 7021cb0ef41Sopenharmony_ci</li> 7031cb0ef41Sopenharmony_ci<li><code>cancel</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Function" class="type"><Function></a> A user-defined function that is called when the 7041cb0ef41Sopenharmony_ci<code>ReadableStream</code> is canceled. 7051cb0ef41Sopenharmony_ci<ul> 7061cb0ef41Sopenharmony_ci<li><code>reason</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Data_types" class="type"><any></a></li> 7071cb0ef41Sopenharmony_ci<li>Returns: A promise fulfilled with <code>undefined</code>.</li> 7081cb0ef41Sopenharmony_ci</ul> 7091cb0ef41Sopenharmony_ci</li> 7101cb0ef41Sopenharmony_ci<li><code>type</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a> Must be <code>'bytes'</code> or <code>undefined</code>.</li> 7111cb0ef41Sopenharmony_ci<li><code>autoAllocateChunkSize</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Number_type" class="type"><number></a> Used only when <code>type</code> is equal to 7121cb0ef41Sopenharmony_ci<code>'bytes'</code>. When set to a non-zero value a view buffer is automatically 7131cb0ef41Sopenharmony_ciallocated to <code>ReadableByteStreamController.byobRequest</code>. When not set 7141cb0ef41Sopenharmony_cione must use stream's internal queues to transfer data via the default 7151cb0ef41Sopenharmony_cireader <code>ReadableStreamDefaultReader</code>.</li> 7161cb0ef41Sopenharmony_ci</ul> 7171cb0ef41Sopenharmony_ci</li> 7181cb0ef41Sopenharmony_ci<li><code>strategy</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object" class="type"><Object></a> 7191cb0ef41Sopenharmony_ci<ul> 7201cb0ef41Sopenharmony_ci<li><code>highWaterMark</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Number_type" class="type"><number></a> The maximum internal queue size before backpressure 7211cb0ef41Sopenharmony_ciis applied.</li> 7221cb0ef41Sopenharmony_ci<li><code>size</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Function" class="type"><Function></a> A user-defined function used to identify the size of each 7231cb0ef41Sopenharmony_cichunk of data. 7241cb0ef41Sopenharmony_ci<ul> 7251cb0ef41Sopenharmony_ci<li><code>chunk</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Data_types" class="type"><any></a></li> 7261cb0ef41Sopenharmony_ci<li>Returns: <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Number_type" class="type"><number></a></li> 7271cb0ef41Sopenharmony_ci</ul> 7281cb0ef41Sopenharmony_ci</li> 7291cb0ef41Sopenharmony_ci</ul> 7301cb0ef41Sopenharmony_ci</li> 7311cb0ef41Sopenharmony_ci</ul> 7321cb0ef41Sopenharmony_ci<!--lint enable maximum-line-length remark-lint--> 7331cb0ef41Sopenharmony_ci<h5><code>readableStream.locked</code><span><a class="mark" href="#readablestreamlocked" id="readablestreamlocked">#</a></span><a aria-hidden="true" class="legacy" id="webstreams_readablestream_locked"></a></h5> 7341cb0ef41Sopenharmony_ci<div class="api_metadata"> 7351cb0ef41Sopenharmony_ci<span>Added in: v16.5.0</span> 7361cb0ef41Sopenharmony_ci</div> 7371cb0ef41Sopenharmony_ci<ul> 7381cb0ef41Sopenharmony_ci<li>Type: <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Boolean_type" class="type"><boolean></a> Set to <code>true</code> if there is an active reader for this 7391cb0ef41Sopenharmony_ci<a href="webstreams.html#class-readablestream" class="type"><ReadableStream></a>.</li> 7401cb0ef41Sopenharmony_ci</ul> 7411cb0ef41Sopenharmony_ci<p>The <code>readableStream.locked</code> property is <code>false</code> by default, and is 7421cb0ef41Sopenharmony_ciswitched to <code>true</code> while there is an active reader consuming the 7431cb0ef41Sopenharmony_cistream's data.</p> 7441cb0ef41Sopenharmony_ci<h5><code>readableStream.cancel([reason])</code><span><a class="mark" href="#readablestreamcancelreason" id="readablestreamcancelreason">#</a></span><a aria-hidden="true" class="legacy" id="webstreams_readablestream_cancel_reason"></a></h5> 7451cb0ef41Sopenharmony_ci<div class="api_metadata"> 7461cb0ef41Sopenharmony_ci<span>Added in: v16.5.0</span> 7471cb0ef41Sopenharmony_ci</div> 7481cb0ef41Sopenharmony_ci<ul> 7491cb0ef41Sopenharmony_ci<li><code>reason</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Data_types" class="type"><any></a></li> 7501cb0ef41Sopenharmony_ci<li>Returns: A promise fulfilled with <code>undefined</code> once cancelation has 7511cb0ef41Sopenharmony_cibeen completed.</li> 7521cb0ef41Sopenharmony_ci</ul> 7531cb0ef41Sopenharmony_ci<h5><code>readableStream.getReader([options])</code><span><a class="mark" href="#readablestreamgetreaderoptions" id="readablestreamgetreaderoptions">#</a></span><a aria-hidden="true" class="legacy" id="webstreams_readablestream_getreader_options"></a></h5> 7541cb0ef41Sopenharmony_ci<div class="api_metadata"> 7551cb0ef41Sopenharmony_ci<span>Added in: v16.5.0</span> 7561cb0ef41Sopenharmony_ci</div> 7571cb0ef41Sopenharmony_ci<ul> 7581cb0ef41Sopenharmony_ci<li><code>options</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object" class="type"><Object></a> 7591cb0ef41Sopenharmony_ci<ul> 7601cb0ef41Sopenharmony_ci<li><code>mode</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a> <code>'byob'</code> or <code>undefined</code></li> 7611cb0ef41Sopenharmony_ci</ul> 7621cb0ef41Sopenharmony_ci</li> 7631cb0ef41Sopenharmony_ci<li>Returns: <a href="webstreams.html#class-readablestreamdefaultreader" class="type"><ReadableStreamDefaultReader></a> | <a href="webstreams.html#class-readablestreambyobreader" class="type"><ReadableStreamBYOBReader></a></li> 7641cb0ef41Sopenharmony_ci</ul> 7651cb0ef41Sopenharmony_ci 7661cb0ef41Sopenharmony_ci<pre class="with-54-chars"><input class="js-flavor-selector" type="checkbox" checked aria-label="Show modern ES modules syntax"><code class="language-js mjs"><span class="hljs-keyword">import</span> { <span class="hljs-title class_">ReadableStream</span> } <span class="hljs-keyword">from</span> <span class="hljs-string">'node:stream/web'</span>; 7671cb0ef41Sopenharmony_ci 7681cb0ef41Sopenharmony_ci<span class="hljs-keyword">const</span> stream = <span class="hljs-keyword">new</span> <span class="hljs-title class_">ReadableStream</span>(); 7691cb0ef41Sopenharmony_ci 7701cb0ef41Sopenharmony_ci<span class="hljs-keyword">const</span> reader = stream.<span class="hljs-title function_">getReader</span>(); 7711cb0ef41Sopenharmony_ci 7721cb0ef41Sopenharmony_ci<span class="hljs-variable language_">console</span>.<span class="hljs-title function_">log</span>(<span class="hljs-keyword">await</span> reader.<span class="hljs-title function_">read</span>());</code><code class="language-js cjs"><span class="hljs-keyword">const</span> { <span class="hljs-title class_">ReadableStream</span> } = <span class="hljs-built_in">require</span>(<span class="hljs-string">'node:stream/web'</span>); 7731cb0ef41Sopenharmony_ci 7741cb0ef41Sopenharmony_ci<span class="hljs-keyword">const</span> stream = <span class="hljs-keyword">new</span> <span class="hljs-title class_">ReadableStream</span>(); 7751cb0ef41Sopenharmony_ci 7761cb0ef41Sopenharmony_ci<span class="hljs-keyword">const</span> reader = stream.<span class="hljs-title function_">getReader</span>(); 7771cb0ef41Sopenharmony_ci 7781cb0ef41Sopenharmony_cireader.<span class="hljs-title function_">read</span>().<span class="hljs-title function_">then</span>(<span class="hljs-variable language_">console</span>.<span class="hljs-property">log</span>);</code><button class="copy-button">copy</button></pre> 7791cb0ef41Sopenharmony_ci<p>Causes the <code>readableStream.locked</code> to be <code>true</code>.</p> 7801cb0ef41Sopenharmony_ci<h5><code>readableStream.pipeThrough(transform[, options])</code><span><a class="mark" href="#readablestreampipethroughtransform-options" id="readablestreampipethroughtransform-options">#</a></span><a aria-hidden="true" class="legacy" id="webstreams_readablestream_pipethrough_transform_options"></a></h5> 7811cb0ef41Sopenharmony_ci<div class="api_metadata"> 7821cb0ef41Sopenharmony_ci<span>Added in: v16.5.0</span> 7831cb0ef41Sopenharmony_ci</div> 7841cb0ef41Sopenharmony_ci<ul> 7851cb0ef41Sopenharmony_ci<li><code>transform</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object" class="type"><Object></a> 7861cb0ef41Sopenharmony_ci<ul> 7871cb0ef41Sopenharmony_ci<li><code>readable</code> <a href="webstreams.html#class-readablestream" class="type"><ReadableStream></a> The <code>ReadableStream</code> to which 7881cb0ef41Sopenharmony_ci<code>transform.writable</code> will push the potentially modified data 7891cb0ef41Sopenharmony_ciis receives from this <code>ReadableStream</code>.</li> 7901cb0ef41Sopenharmony_ci<li><code>writable</code> <a href="webstreams.html#class-writablestream" class="type"><WritableStream></a> The <code>WritableStream</code> to which this 7911cb0ef41Sopenharmony_ci<code>ReadableStream</code>'s data will be written.</li> 7921cb0ef41Sopenharmony_ci</ul> 7931cb0ef41Sopenharmony_ci</li> 7941cb0ef41Sopenharmony_ci<li><code>options</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object" class="type"><Object></a> 7951cb0ef41Sopenharmony_ci<ul> 7961cb0ef41Sopenharmony_ci<li><code>preventAbort</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Boolean_type" class="type"><boolean></a> When <code>true</code>, errors in this <code>ReadableStream</code> 7971cb0ef41Sopenharmony_ciwill not cause <code>transform.writable</code> to be aborted.</li> 7981cb0ef41Sopenharmony_ci<li><code>preventCancel</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Boolean_type" class="type"><boolean></a> When <code>true</code>, errors in the destination 7991cb0ef41Sopenharmony_ci<code>transform.writable</code> do not cause this <code>ReadableStream</code> to be 8001cb0ef41Sopenharmony_cicanceled.</li> 8011cb0ef41Sopenharmony_ci<li><code>preventClose</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Boolean_type" class="type"><boolean></a> When <code>true</code>, closing this <code>ReadableStream</code> 8021cb0ef41Sopenharmony_cidoes not cause <code>transform.writable</code> to be closed.</li> 8031cb0ef41Sopenharmony_ci<li><code>signal</code> <a href="globals.html#class-abortsignal" class="type"><AbortSignal></a> Allows the transfer of data to be canceled 8041cb0ef41Sopenharmony_ciusing an <a href="globals.html#class-abortcontroller" class="type"><AbortController></a>.</li> 8051cb0ef41Sopenharmony_ci</ul> 8061cb0ef41Sopenharmony_ci</li> 8071cb0ef41Sopenharmony_ci<li>Returns: <a href="webstreams.html#class-readablestream" class="type"><ReadableStream></a> From <code>transform.readable</code>.</li> 8081cb0ef41Sopenharmony_ci</ul> 8091cb0ef41Sopenharmony_ci<p>Connects this <a href="webstreams.html#class-readablestream" class="type"><ReadableStream></a> to the pair of <a href="webstreams.html#class-readablestream" class="type"><ReadableStream></a> and 8101cb0ef41Sopenharmony_ci<a href="webstreams.html#class-writablestream" class="type"><WritableStream></a> provided in the <code>transform</code> argument such that the 8111cb0ef41Sopenharmony_cidata from this <a href="webstreams.html#class-readablestream" class="type"><ReadableStream></a> is written in to <code>transform.writable</code>, 8121cb0ef41Sopenharmony_cipossibly transformed, then pushed to <code>transform.readable</code>. Once the 8131cb0ef41Sopenharmony_cipipeline is configured, <code>transform.readable</code> is returned.</p> 8141cb0ef41Sopenharmony_ci<p>Causes the <code>readableStream.locked</code> to be <code>true</code> while the pipe operation 8151cb0ef41Sopenharmony_ciis active.</p> 8161cb0ef41Sopenharmony_ci 8171cb0ef41Sopenharmony_ci<pre class="with-17-chars"><input class="js-flavor-selector" type="checkbox" checked aria-label="Show modern ES modules syntax"><code class="language-js mjs"><span class="hljs-keyword">import</span> { 8181cb0ef41Sopenharmony_ci <span class="hljs-title class_">ReadableStream</span>, 8191cb0ef41Sopenharmony_ci <span class="hljs-title class_">TransformStream</span>, 8201cb0ef41Sopenharmony_ci} <span class="hljs-keyword">from</span> <span class="hljs-string">'node:stream/web'</span>; 8211cb0ef41Sopenharmony_ci 8221cb0ef41Sopenharmony_ci<span class="hljs-keyword">const</span> stream = <span class="hljs-keyword">new</span> <span class="hljs-title class_">ReadableStream</span>({ 8231cb0ef41Sopenharmony_ci <span class="hljs-title function_">start</span>(<span class="hljs-params">controller</span>) { 8241cb0ef41Sopenharmony_ci controller.<span class="hljs-title function_">enqueue</span>(<span class="hljs-string">'a'</span>); 8251cb0ef41Sopenharmony_ci }, 8261cb0ef41Sopenharmony_ci}); 8271cb0ef41Sopenharmony_ci 8281cb0ef41Sopenharmony_ci<span class="hljs-keyword">const</span> transform = <span class="hljs-keyword">new</span> <span class="hljs-title class_">TransformStream</span>({ 8291cb0ef41Sopenharmony_ci <span class="hljs-title function_">transform</span>(<span class="hljs-params">chunk, controller</span>) { 8301cb0ef41Sopenharmony_ci controller.<span class="hljs-title function_">enqueue</span>(chunk.<span class="hljs-title function_">toUpperCase</span>()); 8311cb0ef41Sopenharmony_ci }, 8321cb0ef41Sopenharmony_ci}); 8331cb0ef41Sopenharmony_ci 8341cb0ef41Sopenharmony_ci<span class="hljs-keyword">const</span> transformedStream = stream.<span class="hljs-title function_">pipeThrough</span>(transform); 8351cb0ef41Sopenharmony_ci 8361cb0ef41Sopenharmony_ci<span class="hljs-keyword">for</span> <span class="hljs-keyword">await</span> (<span class="hljs-keyword">const</span> chunk <span class="hljs-keyword">of</span> transformedStream) 8371cb0ef41Sopenharmony_ci <span class="hljs-variable language_">console</span>.<span class="hljs-title function_">log</span>(chunk);</code><code class="language-js cjs"><span class="hljs-keyword">const</span> { 8381cb0ef41Sopenharmony_ci <span class="hljs-title class_">ReadableStream</span>, 8391cb0ef41Sopenharmony_ci <span class="hljs-title class_">TransformStream</span>, 8401cb0ef41Sopenharmony_ci} = <span class="hljs-built_in">require</span>(<span class="hljs-string">'node:stream/web'</span>); 8411cb0ef41Sopenharmony_ci 8421cb0ef41Sopenharmony_ci<span class="hljs-keyword">const</span> stream = <span class="hljs-keyword">new</span> <span class="hljs-title class_">ReadableStream</span>({ 8431cb0ef41Sopenharmony_ci <span class="hljs-title function_">start</span>(<span class="hljs-params">controller</span>) { 8441cb0ef41Sopenharmony_ci controller.<span class="hljs-title function_">enqueue</span>(<span class="hljs-string">'a'</span>); 8451cb0ef41Sopenharmony_ci }, 8461cb0ef41Sopenharmony_ci}); 8471cb0ef41Sopenharmony_ci 8481cb0ef41Sopenharmony_ci<span class="hljs-keyword">const</span> transform = <span class="hljs-keyword">new</span> <span class="hljs-title class_">TransformStream</span>({ 8491cb0ef41Sopenharmony_ci <span class="hljs-title function_">transform</span>(<span class="hljs-params">chunk, controller</span>) { 8501cb0ef41Sopenharmony_ci controller.<span class="hljs-title function_">enqueue</span>(chunk.<span class="hljs-title function_">toUpperCase</span>()); 8511cb0ef41Sopenharmony_ci }, 8521cb0ef41Sopenharmony_ci}); 8531cb0ef41Sopenharmony_ci 8541cb0ef41Sopenharmony_ci<span class="hljs-keyword">const</span> transformedStream = stream.<span class="hljs-title function_">pipeThrough</span>(transform); 8551cb0ef41Sopenharmony_ci 8561cb0ef41Sopenharmony_ci(<span class="hljs-keyword">async</span> () => { 8571cb0ef41Sopenharmony_ci <span class="hljs-keyword">for</span> <span class="hljs-keyword">await</span> (<span class="hljs-keyword">const</span> chunk <span class="hljs-keyword">of</span> transformedStream) 8581cb0ef41Sopenharmony_ci <span class="hljs-variable language_">console</span>.<span class="hljs-title function_">log</span>(chunk); 8591cb0ef41Sopenharmony_ci})();</code><button class="copy-button">copy</button></pre> 8601cb0ef41Sopenharmony_ci<h5><code>readableStream.pipeTo(destination[, options])</code><span><a class="mark" href="#readablestreampipetodestination-options" id="readablestreampipetodestination-options">#</a></span><a aria-hidden="true" class="legacy" id="webstreams_readablestream_pipeto_destination_options"></a></h5> 8611cb0ef41Sopenharmony_ci<div class="api_metadata"> 8621cb0ef41Sopenharmony_ci<span>Added in: v16.5.0</span> 8631cb0ef41Sopenharmony_ci</div> 8641cb0ef41Sopenharmony_ci<ul> 8651cb0ef41Sopenharmony_ci<li><code>destination</code> <a href="webstreams.html#class-writablestream" class="type"><WritableStream></a> A <a href="webstreams.html#class-writablestream" class="type"><WritableStream></a> to which this 8661cb0ef41Sopenharmony_ci<code>ReadableStream</code>'s data will be written.</li> 8671cb0ef41Sopenharmony_ci<li><code>options</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object" class="type"><Object></a> 8681cb0ef41Sopenharmony_ci<ul> 8691cb0ef41Sopenharmony_ci<li><code>preventAbort</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Boolean_type" class="type"><boolean></a> When <code>true</code>, errors in this <code>ReadableStream</code> 8701cb0ef41Sopenharmony_ciwill not cause <code>destination</code> to be aborted.</li> 8711cb0ef41Sopenharmony_ci<li><code>preventCancel</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Boolean_type" class="type"><boolean></a> When <code>true</code>, errors in the <code>destination</code> 8721cb0ef41Sopenharmony_ciwill not cause this <code>ReadableStream</code> to be canceled.</li> 8731cb0ef41Sopenharmony_ci<li><code>preventClose</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Boolean_type" class="type"><boolean></a> When <code>true</code>, closing this <code>ReadableStream</code> 8741cb0ef41Sopenharmony_cidoes not cause <code>destination</code> to be closed.</li> 8751cb0ef41Sopenharmony_ci<li><code>signal</code> <a href="globals.html#class-abortsignal" class="type"><AbortSignal></a> Allows the transfer of data to be canceled 8761cb0ef41Sopenharmony_ciusing an <a href="globals.html#class-abortcontroller" class="type"><AbortController></a>.</li> 8771cb0ef41Sopenharmony_ci</ul> 8781cb0ef41Sopenharmony_ci</li> 8791cb0ef41Sopenharmony_ci<li>Returns: A promise fulfilled with <code>undefined</code></li> 8801cb0ef41Sopenharmony_ci</ul> 8811cb0ef41Sopenharmony_ci<p>Causes the <code>readableStream.locked</code> to be <code>true</code> while the pipe operation 8821cb0ef41Sopenharmony_ciis active.</p> 8831cb0ef41Sopenharmony_ci<h5><code>readableStream.tee()</code><span><a class="mark" href="#readablestreamtee" id="readablestreamtee">#</a></span><a aria-hidden="true" class="legacy" id="webstreams_readablestream_tee"></a></h5> 8841cb0ef41Sopenharmony_ci<div class="api_metadata"> 8851cb0ef41Sopenharmony_ci<details class="changelog"><summary>History</summary> 8861cb0ef41Sopenharmony_ci<table> 8871cb0ef41Sopenharmony_ci<tbody><tr><th>Version</th><th>Changes</th></tr> 8881cb0ef41Sopenharmony_ci<tr><td>v18.10.0</td> 8891cb0ef41Sopenharmony_ci<td><p>Support teeing a readable byte stream.</p></td></tr> 8901cb0ef41Sopenharmony_ci<tr><td>v16.5.0</td> 8911cb0ef41Sopenharmony_ci<td><p><span>Added in: v16.5.0</span></p></td></tr> 8921cb0ef41Sopenharmony_ci</tbody></table> 8931cb0ef41Sopenharmony_ci</details> 8941cb0ef41Sopenharmony_ci</div> 8951cb0ef41Sopenharmony_ci<ul> 8961cb0ef41Sopenharmony_ci<li>Returns: <a href="webstreams.html#class-readablestream" class="type"><ReadableStream[]></a></li> 8971cb0ef41Sopenharmony_ci</ul> 8981cb0ef41Sopenharmony_ci<p>Returns a pair of new <a href="webstreams.html#class-readablestream" class="type"><ReadableStream></a> instances to which this 8991cb0ef41Sopenharmony_ci<code>ReadableStream</code>'s data will be forwarded. Each will receive the 9001cb0ef41Sopenharmony_cisame data.</p> 9011cb0ef41Sopenharmony_ci<p>Causes the <code>readableStream.locked</code> to be <code>true</code>.</p> 9021cb0ef41Sopenharmony_ci<h5><code>readableStream.values([options])</code><span><a class="mark" href="#readablestreamvaluesoptions" id="readablestreamvaluesoptions">#</a></span><a aria-hidden="true" class="legacy" id="webstreams_readablestream_values_options"></a></h5> 9031cb0ef41Sopenharmony_ci<div class="api_metadata"> 9041cb0ef41Sopenharmony_ci<span>Added in: v16.5.0</span> 9051cb0ef41Sopenharmony_ci</div> 9061cb0ef41Sopenharmony_ci<ul> 9071cb0ef41Sopenharmony_ci<li><code>options</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object" class="type"><Object></a> 9081cb0ef41Sopenharmony_ci<ul> 9091cb0ef41Sopenharmony_ci<li><code>preventCancel</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Boolean_type" class="type"><boolean></a> When <code>true</code>, prevents the <a href="webstreams.html#class-readablestream" class="type"><ReadableStream></a> 9101cb0ef41Sopenharmony_cifrom being closed when the async iterator abruptly terminates. 9111cb0ef41Sopenharmony_ci<strong>Default</strong>: <code>false</code>.</li> 9121cb0ef41Sopenharmony_ci</ul> 9131cb0ef41Sopenharmony_ci</li> 9141cb0ef41Sopenharmony_ci</ul> 9151cb0ef41Sopenharmony_ci<p>Creates and returns an async iterator usable for consuming this 9161cb0ef41Sopenharmony_ci<code>ReadableStream</code>'s data.</p> 9171cb0ef41Sopenharmony_ci<p>Causes the <code>readableStream.locked</code> to be <code>true</code> while the async iterator 9181cb0ef41Sopenharmony_ciis active.</p> 9191cb0ef41Sopenharmony_ci<pre><code class="language-js mjs"><span class="hljs-keyword">import</span> { <span class="hljs-title class_">Buffer</span> } <span class="hljs-keyword">from</span> <span class="hljs-string">'node:buffer'</span>; 9201cb0ef41Sopenharmony_ci 9211cb0ef41Sopenharmony_ci<span class="hljs-keyword">const</span> stream = <span class="hljs-keyword">new</span> <span class="hljs-title class_">ReadableStream</span>(<span class="hljs-title function_">getSomeSource</span>()); 9221cb0ef41Sopenharmony_ci 9231cb0ef41Sopenharmony_ci<span class="hljs-keyword">for</span> <span class="hljs-keyword">await</span> (<span class="hljs-keyword">const</span> chunk <span class="hljs-keyword">of</span> stream.<span class="hljs-title function_">values</span>({ <span class="hljs-attr">preventCancel</span>: <span class="hljs-literal">true</span> })) 9241cb0ef41Sopenharmony_ci <span class="hljs-variable language_">console</span>.<span class="hljs-title function_">log</span>(<span class="hljs-title class_">Buffer</span>.<span class="hljs-title function_">from</span>(chunk).<span class="hljs-title function_">toString</span>());</code> <button class="copy-button">copy</button></pre> 9251cb0ef41Sopenharmony_ci<h5>Async Iteration<span><a class="mark" href="#async-iteration" id="async-iteration">#</a></span><a aria-hidden="true" class="legacy" id="webstreams_async_iteration"></a></h5> 9261cb0ef41Sopenharmony_ci<p>The <a href="webstreams.html#class-readablestream" class="type"><ReadableStream></a> object supports the async iterator protocol using 9271cb0ef41Sopenharmony_ci<code>for await</code> syntax.</p> 9281cb0ef41Sopenharmony_ci<pre><code class="language-js mjs"><span class="hljs-keyword">import</span> { <span class="hljs-title class_">Buffer</span> } <span class="hljs-keyword">from</span> <span class="hljs-string">'node:buffer'</span>; 9291cb0ef41Sopenharmony_ci 9301cb0ef41Sopenharmony_ci<span class="hljs-keyword">const</span> stream = <span class="hljs-keyword">new</span> <span class="hljs-title class_">ReadableStream</span>(<span class="hljs-title function_">getSomeSource</span>()); 9311cb0ef41Sopenharmony_ci 9321cb0ef41Sopenharmony_ci<span class="hljs-keyword">for</span> <span class="hljs-keyword">await</span> (<span class="hljs-keyword">const</span> chunk <span class="hljs-keyword">of</span> stream) 9331cb0ef41Sopenharmony_ci <span class="hljs-variable language_">console</span>.<span class="hljs-title function_">log</span>(<span class="hljs-title class_">Buffer</span>.<span class="hljs-title function_">from</span>(chunk).<span class="hljs-title function_">toString</span>());</code> <button class="copy-button">copy</button></pre> 9341cb0ef41Sopenharmony_ci<p>The async iterator will consume the <a href="webstreams.html#class-readablestream" class="type"><ReadableStream></a> until it terminates.</p> 9351cb0ef41Sopenharmony_ci<p>By default, if the async iterator exits early (via either a <code>break</code>, 9361cb0ef41Sopenharmony_ci<code>return</code>, or a <code>throw</code>), the <a href="webstreams.html#class-readablestream" class="type"><ReadableStream></a> will be closed. To prevent 9371cb0ef41Sopenharmony_ciautomatic closing of the <a href="webstreams.html#class-readablestream" class="type"><ReadableStream></a>, use the <code>readableStream.values()</code> 9381cb0ef41Sopenharmony_cimethod to acquire the async iterator and set the <code>preventCancel</code> option to 9391cb0ef41Sopenharmony_ci<code>true</code>.</p> 9401cb0ef41Sopenharmony_ci<p>The <a href="webstreams.html#class-readablestream" class="type"><ReadableStream></a> must not be locked (that is, it must not have an existing 9411cb0ef41Sopenharmony_ciactive reader). During the async iteration, the <a href="webstreams.html#class-readablestream" class="type"><ReadableStream></a> will be locked.</p> 9421cb0ef41Sopenharmony_ci<h5>Transferring with <code>postMessage()</code><span><a class="mark" href="#transferring-with-postmessage" id="transferring-with-postmessage">#</a></span><a aria-hidden="true" class="legacy" id="webstreams_transferring_with_postmessage"></a></h5> 9431cb0ef41Sopenharmony_ci<p>A <a href="webstreams.html#class-readablestream" class="type"><ReadableStream></a> instance can be transferred using a <a href="worker_threads.html#class-messageport" class="type"><MessagePort></a>.</p> 9441cb0ef41Sopenharmony_ci<pre><code class="language-js"><span class="hljs-keyword">const</span> stream = <span class="hljs-keyword">new</span> <span class="hljs-title class_">ReadableStream</span>(<span class="hljs-title function_">getReadableSourceSomehow</span>()); 9451cb0ef41Sopenharmony_ci 9461cb0ef41Sopenharmony_ci<span class="hljs-keyword">const</span> { port1, port2 } = <span class="hljs-keyword">new</span> <span class="hljs-title class_">MessageChannel</span>(); 9471cb0ef41Sopenharmony_ci 9481cb0ef41Sopenharmony_ciport1.<span class="hljs-property">onmessage</span> = <span class="hljs-function">(<span class="hljs-params">{ data }</span>) =></span> { 9491cb0ef41Sopenharmony_ci data.<span class="hljs-title function_">getReader</span>().<span class="hljs-title function_">read</span>().<span class="hljs-title function_">then</span>(<span class="hljs-function">(<span class="hljs-params">chunk</span>) =></span> { 9501cb0ef41Sopenharmony_ci <span class="hljs-variable language_">console</span>.<span class="hljs-title function_">log</span>(chunk); 9511cb0ef41Sopenharmony_ci }); 9521cb0ef41Sopenharmony_ci}; 9531cb0ef41Sopenharmony_ci 9541cb0ef41Sopenharmony_ciport2.<span class="hljs-title function_">postMessage</span>(stream, [stream]);</code> <button class="copy-button">copy</button></pre> 9551cb0ef41Sopenharmony_ci<h4>Class: <code>ReadableStreamDefaultReader</code><span><a class="mark" href="#class-readablestreamdefaultreader" id="class-readablestreamdefaultreader">#</a></span><a aria-hidden="true" class="legacy" id="webstreams_class_readablestreamdefaultreader"></a></h4> 9561cb0ef41Sopenharmony_ci<div class="api_metadata"> 9571cb0ef41Sopenharmony_ci<details class="changelog"><summary>History</summary> 9581cb0ef41Sopenharmony_ci<table> 9591cb0ef41Sopenharmony_ci<tbody><tr><th>Version</th><th>Changes</th></tr> 9601cb0ef41Sopenharmony_ci<tr><td>v18.0.0</td> 9611cb0ef41Sopenharmony_ci<td><p>This class is now exposed on the global object.</p></td></tr> 9621cb0ef41Sopenharmony_ci<tr><td>v16.5.0</td> 9631cb0ef41Sopenharmony_ci<td><p><span>Added in: v16.5.0</span></p></td></tr> 9641cb0ef41Sopenharmony_ci</tbody></table> 9651cb0ef41Sopenharmony_ci</details> 9661cb0ef41Sopenharmony_ci</div> 9671cb0ef41Sopenharmony_ci<p>By default, calling <code>readableStream.getReader()</code> with no arguments 9681cb0ef41Sopenharmony_ciwill return an instance of <code>ReadableStreamDefaultReader</code>. The default 9691cb0ef41Sopenharmony_cireader treats the chunks of data passed through the stream as opaque 9701cb0ef41Sopenharmony_civalues, which allows the <a href="webstreams.html#class-readablestream" class="type"><ReadableStream></a> to work with generally any 9711cb0ef41Sopenharmony_ciJavaScript value.</p> 9721cb0ef41Sopenharmony_ci<h5><code>new ReadableStreamDefaultReader(stream)</code><span><a class="mark" href="#new-readablestreamdefaultreaderstream" id="new-readablestreamdefaultreaderstream">#</a></span><a aria-hidden="true" class="legacy" id="webstreams_new_readablestreamdefaultreader_stream"></a></h5> 9731cb0ef41Sopenharmony_ci<div class="api_metadata"> 9741cb0ef41Sopenharmony_ci<span>Added in: v16.5.0</span> 9751cb0ef41Sopenharmony_ci</div> 9761cb0ef41Sopenharmony_ci<ul> 9771cb0ef41Sopenharmony_ci<li><code>stream</code> <a href="webstreams.html#class-readablestream" class="type"><ReadableStream></a></li> 9781cb0ef41Sopenharmony_ci</ul> 9791cb0ef41Sopenharmony_ci<p>Creates a new <a href="webstreams.html#class-readablestreamdefaultreader" class="type"><ReadableStreamDefaultReader></a> that is locked to the 9801cb0ef41Sopenharmony_cigiven <a href="webstreams.html#class-readablestream" class="type"><ReadableStream></a>.</p> 9811cb0ef41Sopenharmony_ci<h5><code>readableStreamDefaultReader.cancel([reason])</code><span><a class="mark" href="#readablestreamdefaultreadercancelreason" id="readablestreamdefaultreadercancelreason">#</a></span><a aria-hidden="true" class="legacy" id="webstreams_readablestreamdefaultreader_cancel_reason"></a></h5> 9821cb0ef41Sopenharmony_ci<div class="api_metadata"> 9831cb0ef41Sopenharmony_ci<span>Added in: v16.5.0</span> 9841cb0ef41Sopenharmony_ci</div> 9851cb0ef41Sopenharmony_ci<ul> 9861cb0ef41Sopenharmony_ci<li><code>reason</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Data_types" class="type"><any></a></li> 9871cb0ef41Sopenharmony_ci<li>Returns: A promise fulfilled with <code>undefined</code>.</li> 9881cb0ef41Sopenharmony_ci</ul> 9891cb0ef41Sopenharmony_ci<p>Cancels the <a href="webstreams.html#class-readablestream" class="type"><ReadableStream></a> and returns a promise that is fulfilled 9901cb0ef41Sopenharmony_ciwhen the underlying stream has been canceled.</p> 9911cb0ef41Sopenharmony_ci<h5><code>readableStreamDefaultReader.closed</code><span><a class="mark" href="#readablestreamdefaultreaderclosed" id="readablestreamdefaultreaderclosed">#</a></span><a aria-hidden="true" class="legacy" id="webstreams_readablestreamdefaultreader_closed"></a></h5> 9921cb0ef41Sopenharmony_ci<div class="api_metadata"> 9931cb0ef41Sopenharmony_ci<span>Added in: v16.5.0</span> 9941cb0ef41Sopenharmony_ci</div> 9951cb0ef41Sopenharmony_ci<ul> 9961cb0ef41Sopenharmony_ci<li>Type: <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Promise" class="type"><Promise></a> Fulfilled with <code>undefined</code> when the associated 9971cb0ef41Sopenharmony_ci<a href="webstreams.html#class-readablestream" class="type"><ReadableStream></a> is closed or rejected if the stream errors or the reader's 9981cb0ef41Sopenharmony_cilock is released before the stream finishes closing.</li> 9991cb0ef41Sopenharmony_ci</ul> 10001cb0ef41Sopenharmony_ci<h5><code>readableStreamDefaultReader.read()</code><span><a class="mark" href="#readablestreamdefaultreaderread" id="readablestreamdefaultreaderread">#</a></span><a aria-hidden="true" class="legacy" id="webstreams_readablestreamdefaultreader_read"></a></h5> 10011cb0ef41Sopenharmony_ci<div class="api_metadata"> 10021cb0ef41Sopenharmony_ci<span>Added in: v16.5.0</span> 10031cb0ef41Sopenharmony_ci</div> 10041cb0ef41Sopenharmony_ci<ul> 10051cb0ef41Sopenharmony_ci<li>Returns: A promise fulfilled with an object: 10061cb0ef41Sopenharmony_ci<ul> 10071cb0ef41Sopenharmony_ci<li><code>value</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/ArrayBuffer" class="type"><ArrayBuffer></a></li> 10081cb0ef41Sopenharmony_ci<li><code>done</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Boolean_type" class="type"><boolean></a></li> 10091cb0ef41Sopenharmony_ci</ul> 10101cb0ef41Sopenharmony_ci</li> 10111cb0ef41Sopenharmony_ci</ul> 10121cb0ef41Sopenharmony_ci<p>Requests the next chunk of data from the underlying <a href="webstreams.html#class-readablestream" class="type"><ReadableStream></a> 10131cb0ef41Sopenharmony_ciand returns a promise that is fulfilled with the data once it is 10141cb0ef41Sopenharmony_ciavailable.</p> 10151cb0ef41Sopenharmony_ci<h5><code>readableStreamDefaultReader.releaseLock()</code><span><a class="mark" href="#readablestreamdefaultreaderreleaselock" id="readablestreamdefaultreaderreleaselock">#</a></span><a aria-hidden="true" class="legacy" id="webstreams_readablestreamdefaultreader_releaselock"></a></h5> 10161cb0ef41Sopenharmony_ci<div class="api_metadata"> 10171cb0ef41Sopenharmony_ci<span>Added in: v16.5.0</span> 10181cb0ef41Sopenharmony_ci</div> 10191cb0ef41Sopenharmony_ci<p>Releases this reader's lock on the underlying <a href="webstreams.html#class-readablestream" class="type"><ReadableStream></a>.</p> 10201cb0ef41Sopenharmony_ci<h4>Class: <code>ReadableStreamBYOBReader</code><span><a class="mark" href="#class-readablestreambyobreader" id="class-readablestreambyobreader">#</a></span><a aria-hidden="true" class="legacy" id="webstreams_class_readablestreambyobreader"></a></h4> 10211cb0ef41Sopenharmony_ci<div class="api_metadata"> 10221cb0ef41Sopenharmony_ci<details class="changelog"><summary>History</summary> 10231cb0ef41Sopenharmony_ci<table> 10241cb0ef41Sopenharmony_ci<tbody><tr><th>Version</th><th>Changes</th></tr> 10251cb0ef41Sopenharmony_ci<tr><td>v18.0.0</td> 10261cb0ef41Sopenharmony_ci<td><p>This class is now exposed on the global object.</p></td></tr> 10271cb0ef41Sopenharmony_ci<tr><td>v16.5.0</td> 10281cb0ef41Sopenharmony_ci<td><p><span>Added in: v16.5.0</span></p></td></tr> 10291cb0ef41Sopenharmony_ci</tbody></table> 10301cb0ef41Sopenharmony_ci</details> 10311cb0ef41Sopenharmony_ci</div> 10321cb0ef41Sopenharmony_ci<p>The <code>ReadableStreamBYOBReader</code> is an alternative consumer for 10331cb0ef41Sopenharmony_cibyte-oriented <a href="webstreams.html#class-readablestream" class="type"><ReadableStream></a>s (those that are created with 10341cb0ef41Sopenharmony_ci<code>underlyingSource.type</code> set equal to <code>'bytes'</code> when the 10351cb0ef41Sopenharmony_ci<code>ReadableStream</code> was created).</p> 10361cb0ef41Sopenharmony_ci<p>The <code>BYOB</code> is short for "bring your own buffer". This is a 10371cb0ef41Sopenharmony_cipattern that allows for more efficient reading of byte-oriented 10381cb0ef41Sopenharmony_cidata that avoids extraneous copying.</p> 10391cb0ef41Sopenharmony_ci<pre><code class="language-js mjs"><span class="hljs-keyword">import</span> { 10401cb0ef41Sopenharmony_ci open, 10411cb0ef41Sopenharmony_ci} <span class="hljs-keyword">from</span> <span class="hljs-string">'node:fs/promises'</span>; 10421cb0ef41Sopenharmony_ci 10431cb0ef41Sopenharmony_ci<span class="hljs-keyword">import</span> { 10441cb0ef41Sopenharmony_ci <span class="hljs-title class_">ReadableStream</span>, 10451cb0ef41Sopenharmony_ci} <span class="hljs-keyword">from</span> <span class="hljs-string">'node:stream/web'</span>; 10461cb0ef41Sopenharmony_ci 10471cb0ef41Sopenharmony_ci<span class="hljs-keyword">import</span> { <span class="hljs-title class_">Buffer</span> } <span class="hljs-keyword">from</span> <span class="hljs-string">'node:buffer'</span>; 10481cb0ef41Sopenharmony_ci 10491cb0ef41Sopenharmony_ci<span class="hljs-keyword">class</span> <span class="hljs-title class_">Source</span> { 10501cb0ef41Sopenharmony_ci type = <span class="hljs-string">'bytes'</span>; 10511cb0ef41Sopenharmony_ci autoAllocateChunkSize = <span class="hljs-number">1024</span>; 10521cb0ef41Sopenharmony_ci 10531cb0ef41Sopenharmony_ci <span class="hljs-keyword">async</span> <span class="hljs-title function_">start</span>(<span class="hljs-params">controller</span>) { 10541cb0ef41Sopenharmony_ci <span class="hljs-variable language_">this</span>.<span class="hljs-property">file</span> = <span class="hljs-keyword">await</span> <span class="hljs-title function_">open</span>(<span class="hljs-keyword">new</span> <span class="hljs-title function_">URL</span>(<span class="hljs-keyword">import</span>.<span class="hljs-property">meta</span>.<span class="hljs-property">url</span>)); 10551cb0ef41Sopenharmony_ci <span class="hljs-variable language_">this</span>.<span class="hljs-property">controller</span> = controller; 10561cb0ef41Sopenharmony_ci } 10571cb0ef41Sopenharmony_ci 10581cb0ef41Sopenharmony_ci <span class="hljs-keyword">async</span> <span class="hljs-title function_">pull</span>(<span class="hljs-params">controller</span>) { 10591cb0ef41Sopenharmony_ci <span class="hljs-keyword">const</span> view = controller.<span class="hljs-property">byobRequest</span>?.<span class="hljs-property">view</span>; 10601cb0ef41Sopenharmony_ci <span class="hljs-keyword">const</span> { 10611cb0ef41Sopenharmony_ci bytesRead, 10621cb0ef41Sopenharmony_ci } = <span class="hljs-keyword">await</span> <span class="hljs-variable language_">this</span>.<span class="hljs-property">file</span>.<span class="hljs-title function_">read</span>({ 10631cb0ef41Sopenharmony_ci <span class="hljs-attr">buffer</span>: view, 10641cb0ef41Sopenharmony_ci <span class="hljs-attr">offset</span>: view.<span class="hljs-property">byteOffset</span>, 10651cb0ef41Sopenharmony_ci <span class="hljs-attr">length</span>: view.<span class="hljs-property">byteLength</span>, 10661cb0ef41Sopenharmony_ci }); 10671cb0ef41Sopenharmony_ci 10681cb0ef41Sopenharmony_ci <span class="hljs-keyword">if</span> (bytesRead === <span class="hljs-number">0</span>) { 10691cb0ef41Sopenharmony_ci <span class="hljs-keyword">await</span> <span class="hljs-variable language_">this</span>.<span class="hljs-property">file</span>.<span class="hljs-title function_">close</span>(); 10701cb0ef41Sopenharmony_ci <span class="hljs-variable language_">this</span>.<span class="hljs-property">controller</span>.<span class="hljs-title function_">close</span>(); 10711cb0ef41Sopenharmony_ci } 10721cb0ef41Sopenharmony_ci controller.<span class="hljs-property">byobRequest</span>.<span class="hljs-title function_">respond</span>(bytesRead); 10731cb0ef41Sopenharmony_ci } 10741cb0ef41Sopenharmony_ci} 10751cb0ef41Sopenharmony_ci 10761cb0ef41Sopenharmony_ci<span class="hljs-keyword">const</span> stream = <span class="hljs-keyword">new</span> <span class="hljs-title class_">ReadableStream</span>(<span class="hljs-keyword">new</span> <span class="hljs-title class_">Source</span>()); 10771cb0ef41Sopenharmony_ci 10781cb0ef41Sopenharmony_ci<span class="hljs-keyword">async</span> <span class="hljs-keyword">function</span> <span class="hljs-title function_">read</span>(<span class="hljs-params">stream</span>) { 10791cb0ef41Sopenharmony_ci <span class="hljs-keyword">const</span> reader = stream.<span class="hljs-title function_">getReader</span>({ <span class="hljs-attr">mode</span>: <span class="hljs-string">'byob'</span> }); 10801cb0ef41Sopenharmony_ci 10811cb0ef41Sopenharmony_ci <span class="hljs-keyword">const</span> chunks = []; 10821cb0ef41Sopenharmony_ci <span class="hljs-keyword">let</span> result; 10831cb0ef41Sopenharmony_ci <span class="hljs-keyword">do</span> { 10841cb0ef41Sopenharmony_ci result = <span class="hljs-keyword">await</span> reader.<span class="hljs-title function_">read</span>(<span class="hljs-title class_">Buffer</span>.<span class="hljs-title function_">alloc</span>(<span class="hljs-number">100</span>)); 10851cb0ef41Sopenharmony_ci <span class="hljs-keyword">if</span> (result.<span class="hljs-property">value</span> !== <span class="hljs-literal">undefined</span>) 10861cb0ef41Sopenharmony_ci chunks.<span class="hljs-title function_">push</span>(<span class="hljs-title class_">Buffer</span>.<span class="hljs-title function_">from</span>(result.<span class="hljs-property">value</span>)); 10871cb0ef41Sopenharmony_ci } <span class="hljs-keyword">while</span> (!result.<span class="hljs-property">done</span>); 10881cb0ef41Sopenharmony_ci 10891cb0ef41Sopenharmony_ci <span class="hljs-keyword">return</span> <span class="hljs-title class_">Buffer</span>.<span class="hljs-title function_">concat</span>(chunks); 10901cb0ef41Sopenharmony_ci} 10911cb0ef41Sopenharmony_ci 10921cb0ef41Sopenharmony_ci<span class="hljs-keyword">const</span> data = <span class="hljs-keyword">await</span> <span class="hljs-title function_">read</span>(stream); 10931cb0ef41Sopenharmony_ci<span class="hljs-variable language_">console</span>.<span class="hljs-title function_">log</span>(<span class="hljs-title class_">Buffer</span>.<span class="hljs-title function_">from</span>(data).<span class="hljs-title function_">toString</span>());</code> <button class="copy-button">copy</button></pre> 10941cb0ef41Sopenharmony_ci<h5><code>new ReadableStreamBYOBReader(stream)</code><span><a class="mark" href="#new-readablestreambyobreaderstream" id="new-readablestreambyobreaderstream">#</a></span><a aria-hidden="true" class="legacy" id="webstreams_new_readablestreambyobreader_stream"></a></h5> 10951cb0ef41Sopenharmony_ci<div class="api_metadata"> 10961cb0ef41Sopenharmony_ci<span>Added in: v16.5.0</span> 10971cb0ef41Sopenharmony_ci</div> 10981cb0ef41Sopenharmony_ci<ul> 10991cb0ef41Sopenharmony_ci<li><code>stream</code> <a href="webstreams.html#class-readablestream" class="type"><ReadableStream></a></li> 11001cb0ef41Sopenharmony_ci</ul> 11011cb0ef41Sopenharmony_ci<p>Creates a new <code>ReadableStreamBYOBReader</code> that is locked to the 11021cb0ef41Sopenharmony_cigiven <a href="webstreams.html#class-readablestream" class="type"><ReadableStream></a>.</p> 11031cb0ef41Sopenharmony_ci<h5><code>readableStreamBYOBReader.cancel([reason])</code><span><a class="mark" href="#readablestreambyobreadercancelreason" id="readablestreambyobreadercancelreason">#</a></span><a aria-hidden="true" class="legacy" id="webstreams_readablestreambyobreader_cancel_reason"></a></h5> 11041cb0ef41Sopenharmony_ci<div class="api_metadata"> 11051cb0ef41Sopenharmony_ci<span>Added in: v16.5.0</span> 11061cb0ef41Sopenharmony_ci</div> 11071cb0ef41Sopenharmony_ci<ul> 11081cb0ef41Sopenharmony_ci<li><code>reason</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Data_types" class="type"><any></a></li> 11091cb0ef41Sopenharmony_ci<li>Returns: A promise fulfilled with <code>undefined</code>.</li> 11101cb0ef41Sopenharmony_ci</ul> 11111cb0ef41Sopenharmony_ci<p>Cancels the <a href="webstreams.html#class-readablestream" class="type"><ReadableStream></a> and returns a promise that is fulfilled 11121cb0ef41Sopenharmony_ciwhen the underlying stream has been canceled.</p> 11131cb0ef41Sopenharmony_ci<h5><code>readableStreamBYOBReader.closed</code><span><a class="mark" href="#readablestreambyobreaderclosed" id="readablestreambyobreaderclosed">#</a></span><a aria-hidden="true" class="legacy" id="webstreams_readablestreambyobreader_closed"></a></h5> 11141cb0ef41Sopenharmony_ci<div class="api_metadata"> 11151cb0ef41Sopenharmony_ci<span>Added in: v16.5.0</span> 11161cb0ef41Sopenharmony_ci</div> 11171cb0ef41Sopenharmony_ci<ul> 11181cb0ef41Sopenharmony_ci<li>Type: <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Promise" class="type"><Promise></a> Fulfilled with <code>undefined</code> when the associated 11191cb0ef41Sopenharmony_ci<a href="webstreams.html#class-readablestream" class="type"><ReadableStream></a> is closed or rejected if the stream errors or the reader's 11201cb0ef41Sopenharmony_cilock is released before the stream finishes closing.</li> 11211cb0ef41Sopenharmony_ci</ul> 11221cb0ef41Sopenharmony_ci<h5><code>readableStreamBYOBReader.read(view)</code><span><a class="mark" href="#readablestreambyobreaderreadview" id="readablestreambyobreaderreadview">#</a></span><a aria-hidden="true" class="legacy" id="webstreams_readablestreambyobreader_read_view"></a></h5> 11231cb0ef41Sopenharmony_ci<div class="api_metadata"> 11241cb0ef41Sopenharmony_ci<span>Added in: v16.5.0</span> 11251cb0ef41Sopenharmony_ci</div> 11261cb0ef41Sopenharmony_ci<ul> 11271cb0ef41Sopenharmony_ci<li><code>view</code> <a href="buffer.html#class-buffer" class="type"><Buffer></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/TypedArray" class="type"><TypedArray></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/DataView" class="type"><DataView></a></li> 11281cb0ef41Sopenharmony_ci<li>Returns: A promise fulfilled with an object: 11291cb0ef41Sopenharmony_ci<ul> 11301cb0ef41Sopenharmony_ci<li><code>value</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/ArrayBuffer" class="type"><ArrayBuffer></a></li> 11311cb0ef41Sopenharmony_ci<li><code>done</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Boolean_type" class="type"><boolean></a></li> 11321cb0ef41Sopenharmony_ci</ul> 11331cb0ef41Sopenharmony_ci</li> 11341cb0ef41Sopenharmony_ci</ul> 11351cb0ef41Sopenharmony_ci<p>Requests the next chunk of data from the underlying <a href="webstreams.html#class-readablestream" class="type"><ReadableStream></a> 11361cb0ef41Sopenharmony_ciand returns a promise that is fulfilled with the data once it is 11371cb0ef41Sopenharmony_ciavailable.</p> 11381cb0ef41Sopenharmony_ci<p>Do not pass a pooled <a href="buffer.html#class-buffer" class="type"><Buffer></a> object instance in to this method. 11391cb0ef41Sopenharmony_ciPooled <code>Buffer</code> objects are created using <code>Buffer.allocUnsafe()</code>, 11401cb0ef41Sopenharmony_cior <code>Buffer.from()</code>, or are often returned by various <code>node:fs</code> module 11411cb0ef41Sopenharmony_cicallbacks. These types of <code>Buffer</code>s use a shared underlying 11421cb0ef41Sopenharmony_ci<a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/ArrayBuffer" class="type"><ArrayBuffer></a> object that contains all of the data from all of 11431cb0ef41Sopenharmony_cithe pooled <code>Buffer</code> instances. When a <code>Buffer</code>, <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/TypedArray" class="type"><TypedArray></a>, 11441cb0ef41Sopenharmony_cior <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/DataView" class="type"><DataView></a> is passed in to <code>readableStreamBYOBReader.read()</code>, 11451cb0ef41Sopenharmony_cithe view's underlying <code>ArrayBuffer</code> is <em>detached</em>, invalidating 11461cb0ef41Sopenharmony_ciall existing views that may exist on that <code>ArrayBuffer</code>. This 11471cb0ef41Sopenharmony_cican have disastrous consequences for your application.</p> 11481cb0ef41Sopenharmony_ci<h5><code>readableStreamBYOBReader.releaseLock()</code><span><a class="mark" href="#readablestreambyobreaderreleaselock" id="readablestreambyobreaderreleaselock">#</a></span><a aria-hidden="true" class="legacy" id="webstreams_readablestreambyobreader_releaselock"></a></h5> 11491cb0ef41Sopenharmony_ci<div class="api_metadata"> 11501cb0ef41Sopenharmony_ci<span>Added in: v16.5.0</span> 11511cb0ef41Sopenharmony_ci</div> 11521cb0ef41Sopenharmony_ci<p>Releases this reader's lock on the underlying <a href="webstreams.html#class-readablestream" class="type"><ReadableStream></a>.</p> 11531cb0ef41Sopenharmony_ci<h4>Class: <code>ReadableStreamDefaultController</code><span><a class="mark" href="#class-readablestreamdefaultcontroller" id="class-readablestreamdefaultcontroller">#</a></span><a aria-hidden="true" class="legacy" id="webstreams_class_readablestreamdefaultcontroller"></a></h4> 11541cb0ef41Sopenharmony_ci<div class="api_metadata"> 11551cb0ef41Sopenharmony_ci<span>Added in: v16.5.0</span> 11561cb0ef41Sopenharmony_ci</div> 11571cb0ef41Sopenharmony_ci<p>Every <a href="webstreams.html#class-readablestream" class="type"><ReadableStream></a> has a controller that is responsible for 11581cb0ef41Sopenharmony_cithe internal state and management of the stream's queue. The 11591cb0ef41Sopenharmony_ci<code>ReadableStreamDefaultController</code> is the default controller 11601cb0ef41Sopenharmony_ciimplementation for <code>ReadableStream</code>s that are not byte-oriented.</p> 11611cb0ef41Sopenharmony_ci<h5><code>readableStreamDefaultController.close()</code><span><a class="mark" href="#readablestreamdefaultcontrollerclose" id="readablestreamdefaultcontrollerclose">#</a></span><a aria-hidden="true" class="legacy" id="webstreams_readablestreamdefaultcontroller_close"></a></h5> 11621cb0ef41Sopenharmony_ci<div class="api_metadata"> 11631cb0ef41Sopenharmony_ci<span>Added in: v16.5.0</span> 11641cb0ef41Sopenharmony_ci</div> 11651cb0ef41Sopenharmony_ci<p>Closes the <a href="webstreams.html#class-readablestream" class="type"><ReadableStream></a> to which this controller is associated.</p> 11661cb0ef41Sopenharmony_ci<h5><code>readableStreamDefaultController.desiredSize</code><span><a class="mark" href="#readablestreamdefaultcontrollerdesiredsize" id="readablestreamdefaultcontrollerdesiredsize">#</a></span><a aria-hidden="true" class="legacy" id="webstreams_readablestreamdefaultcontroller_desiredsize"></a></h5> 11671cb0ef41Sopenharmony_ci<div class="api_metadata"> 11681cb0ef41Sopenharmony_ci<span>Added in: v16.5.0</span> 11691cb0ef41Sopenharmony_ci</div> 11701cb0ef41Sopenharmony_ci<ul> 11711cb0ef41Sopenharmony_ci<li>Type: <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Number_type" class="type"><number></a></li> 11721cb0ef41Sopenharmony_ci</ul> 11731cb0ef41Sopenharmony_ci<p>Returns the amount of data remaining to fill the <a href="webstreams.html#class-readablestream" class="type"><ReadableStream></a>'s 11741cb0ef41Sopenharmony_ciqueue.</p> 11751cb0ef41Sopenharmony_ci<h5><code>readableStreamDefaultController.enqueue([chunk])</code><span><a class="mark" href="#readablestreamdefaultcontrollerenqueuechunk" id="readablestreamdefaultcontrollerenqueuechunk">#</a></span><a aria-hidden="true" class="legacy" id="webstreams_readablestreamdefaultcontroller_enqueue_chunk"></a></h5> 11761cb0ef41Sopenharmony_ci<div class="api_metadata"> 11771cb0ef41Sopenharmony_ci<span>Added in: v16.5.0</span> 11781cb0ef41Sopenharmony_ci</div> 11791cb0ef41Sopenharmony_ci<ul> 11801cb0ef41Sopenharmony_ci<li><code>chunk</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Data_types" class="type"><any></a></li> 11811cb0ef41Sopenharmony_ci</ul> 11821cb0ef41Sopenharmony_ci<p>Appends a new chunk of data to the <a href="webstreams.html#class-readablestream" class="type"><ReadableStream></a>'s queue.</p> 11831cb0ef41Sopenharmony_ci<h5><code>readableStreamDefaultController.error([error])</code><span><a class="mark" href="#readablestreamdefaultcontrollererrorerror" id="readablestreamdefaultcontrollererrorerror">#</a></span><a aria-hidden="true" class="legacy" id="webstreams_readablestreamdefaultcontroller_error_error"></a></h5> 11841cb0ef41Sopenharmony_ci<div class="api_metadata"> 11851cb0ef41Sopenharmony_ci<span>Added in: v16.5.0</span> 11861cb0ef41Sopenharmony_ci</div> 11871cb0ef41Sopenharmony_ci<ul> 11881cb0ef41Sopenharmony_ci<li><code>error</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Data_types" class="type"><any></a></li> 11891cb0ef41Sopenharmony_ci</ul> 11901cb0ef41Sopenharmony_ci<p>Signals an error that causes the <a href="webstreams.html#class-readablestream" class="type"><ReadableStream></a> to error and close.</p> 11911cb0ef41Sopenharmony_ci<h4>Class: <code>ReadableByteStreamController</code><span><a class="mark" href="#class-readablebytestreamcontroller" id="class-readablebytestreamcontroller">#</a></span><a aria-hidden="true" class="legacy" id="webstreams_class_readablebytestreamcontroller"></a></h4> 11921cb0ef41Sopenharmony_ci<div class="api_metadata"> 11931cb0ef41Sopenharmony_ci<details class="changelog"><summary>History</summary> 11941cb0ef41Sopenharmony_ci<table> 11951cb0ef41Sopenharmony_ci<tbody><tr><th>Version</th><th>Changes</th></tr> 11961cb0ef41Sopenharmony_ci<tr><td>v18.10.0</td> 11971cb0ef41Sopenharmony_ci<td><p>Support handling a BYOB pull request from a released reader.</p></td></tr> 11981cb0ef41Sopenharmony_ci<tr><td>v16.5.0</td> 11991cb0ef41Sopenharmony_ci<td><p><span>Added in: v16.5.0</span></p></td></tr> 12001cb0ef41Sopenharmony_ci</tbody></table> 12011cb0ef41Sopenharmony_ci</details> 12021cb0ef41Sopenharmony_ci</div> 12031cb0ef41Sopenharmony_ci<p>Every <a href="webstreams.html#class-readablestream" class="type"><ReadableStream></a> has a controller that is responsible for 12041cb0ef41Sopenharmony_cithe internal state and management of the stream's queue. The 12051cb0ef41Sopenharmony_ci<code>ReadableByteStreamController</code> is for byte-oriented <code>ReadableStream</code>s.</p> 12061cb0ef41Sopenharmony_ci<h5><code>readableByteStreamController.byobRequest</code><span><a class="mark" href="#readablebytestreamcontrollerbyobrequest" id="readablebytestreamcontrollerbyobrequest">#</a></span><a aria-hidden="true" class="legacy" id="webstreams_readablebytestreamcontroller_byobrequest"></a></h5> 12071cb0ef41Sopenharmony_ci<div class="api_metadata"> 12081cb0ef41Sopenharmony_ci<span>Added in: v16.5.0</span> 12091cb0ef41Sopenharmony_ci</div> 12101cb0ef41Sopenharmony_ci<ul> 12111cb0ef41Sopenharmony_ci<li>Type: <a href="webstreams.html#class-readablestreambyobrequest" class="type"><ReadableStreamBYOBRequest></a></li> 12121cb0ef41Sopenharmony_ci</ul> 12131cb0ef41Sopenharmony_ci<h5><code>readableByteStreamController.close()</code><span><a class="mark" href="#readablebytestreamcontrollerclose" id="readablebytestreamcontrollerclose">#</a></span><a aria-hidden="true" class="legacy" id="webstreams_readablebytestreamcontroller_close"></a></h5> 12141cb0ef41Sopenharmony_ci<div class="api_metadata"> 12151cb0ef41Sopenharmony_ci<span>Added in: v16.5.0</span> 12161cb0ef41Sopenharmony_ci</div> 12171cb0ef41Sopenharmony_ci<p>Closes the <a href="webstreams.html#class-readablestream" class="type"><ReadableStream></a> to which this controller is associated.</p> 12181cb0ef41Sopenharmony_ci<h5><code>readableByteStreamController.desiredSize</code><span><a class="mark" href="#readablebytestreamcontrollerdesiredsize" id="readablebytestreamcontrollerdesiredsize">#</a></span><a aria-hidden="true" class="legacy" id="webstreams_readablebytestreamcontroller_desiredsize"></a></h5> 12191cb0ef41Sopenharmony_ci<div class="api_metadata"> 12201cb0ef41Sopenharmony_ci<span>Added in: v16.5.0</span> 12211cb0ef41Sopenharmony_ci</div> 12221cb0ef41Sopenharmony_ci<ul> 12231cb0ef41Sopenharmony_ci<li>Type: <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Number_type" class="type"><number></a></li> 12241cb0ef41Sopenharmony_ci</ul> 12251cb0ef41Sopenharmony_ci<p>Returns the amount of data remaining to fill the <a href="webstreams.html#class-readablestream" class="type"><ReadableStream></a>'s 12261cb0ef41Sopenharmony_ciqueue.</p> 12271cb0ef41Sopenharmony_ci<h5><code>readableByteStreamController.enqueue(chunk)</code><span><a class="mark" href="#readablebytestreamcontrollerenqueuechunk" id="readablebytestreamcontrollerenqueuechunk">#</a></span><a aria-hidden="true" class="legacy" id="webstreams_readablebytestreamcontroller_enqueue_chunk"></a></h5> 12281cb0ef41Sopenharmony_ci<div class="api_metadata"> 12291cb0ef41Sopenharmony_ci<span>Added in: v16.5.0</span> 12301cb0ef41Sopenharmony_ci</div> 12311cb0ef41Sopenharmony_ci<ul> 12321cb0ef41Sopenharmony_ci<li><code>chunk</code>: <a href="buffer.html#class-buffer" class="type"><Buffer></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/TypedArray" class="type"><TypedArray></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/DataView" class="type"><DataView></a></li> 12331cb0ef41Sopenharmony_ci</ul> 12341cb0ef41Sopenharmony_ci<p>Appends a new chunk of data to the <a href="webstreams.html#class-readablestream" class="type"><ReadableStream></a>'s queue.</p> 12351cb0ef41Sopenharmony_ci<h5><code>readableByteStreamController.error([error])</code><span><a class="mark" href="#readablebytestreamcontrollererrorerror" id="readablebytestreamcontrollererrorerror">#</a></span><a aria-hidden="true" class="legacy" id="webstreams_readablebytestreamcontroller_error_error"></a></h5> 12361cb0ef41Sopenharmony_ci<div class="api_metadata"> 12371cb0ef41Sopenharmony_ci<span>Added in: v16.5.0</span> 12381cb0ef41Sopenharmony_ci</div> 12391cb0ef41Sopenharmony_ci<ul> 12401cb0ef41Sopenharmony_ci<li><code>error</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Data_types" class="type"><any></a></li> 12411cb0ef41Sopenharmony_ci</ul> 12421cb0ef41Sopenharmony_ci<p>Signals an error that causes the <a href="webstreams.html#class-readablestream" class="type"><ReadableStream></a> to error and close.</p> 12431cb0ef41Sopenharmony_ci<h4>Class: <code>ReadableStreamBYOBRequest</code><span><a class="mark" href="#class-readablestreambyobrequest" id="class-readablestreambyobrequest">#</a></span><a aria-hidden="true" class="legacy" id="webstreams_class_readablestreambyobrequest"></a></h4> 12441cb0ef41Sopenharmony_ci<div class="api_metadata"> 12451cb0ef41Sopenharmony_ci<details class="changelog"><summary>History</summary> 12461cb0ef41Sopenharmony_ci<table> 12471cb0ef41Sopenharmony_ci<tbody><tr><th>Version</th><th>Changes</th></tr> 12481cb0ef41Sopenharmony_ci<tr><td>v18.0.0</td> 12491cb0ef41Sopenharmony_ci<td><p>This class is now exposed on the global object.</p></td></tr> 12501cb0ef41Sopenharmony_ci<tr><td>v16.5.0</td> 12511cb0ef41Sopenharmony_ci<td><p><span>Added in: v16.5.0</span></p></td></tr> 12521cb0ef41Sopenharmony_ci</tbody></table> 12531cb0ef41Sopenharmony_ci</details> 12541cb0ef41Sopenharmony_ci</div> 12551cb0ef41Sopenharmony_ci<p>When using <code>ReadableByteStreamController</code> in byte-oriented 12561cb0ef41Sopenharmony_cistreams, and when using the <code>ReadableStreamBYOBReader</code>, 12571cb0ef41Sopenharmony_cithe <code>readableByteStreamController.byobRequest</code> property 12581cb0ef41Sopenharmony_ciprovides access to a <code>ReadableStreamBYOBRequest</code> instance 12591cb0ef41Sopenharmony_cithat represents the current read request. The object 12601cb0ef41Sopenharmony_ciis used to gain access to the <code>ArrayBuffer</code>/<code>TypedArray</code> 12611cb0ef41Sopenharmony_cithat has been provided for the read request to fill, 12621cb0ef41Sopenharmony_ciand provides methods for signaling that the data has 12631cb0ef41Sopenharmony_cibeen provided.</p> 12641cb0ef41Sopenharmony_ci<h5><code>readableStreamBYOBRequest.respond(bytesWritten)</code><span><a class="mark" href="#readablestreambyobrequestrespondbyteswritten" id="readablestreambyobrequestrespondbyteswritten">#</a></span><a aria-hidden="true" class="legacy" id="webstreams_readablestreambyobrequest_respond_byteswritten"></a></h5> 12651cb0ef41Sopenharmony_ci<div class="api_metadata"> 12661cb0ef41Sopenharmony_ci<span>Added in: v16.5.0</span> 12671cb0ef41Sopenharmony_ci</div> 12681cb0ef41Sopenharmony_ci<ul> 12691cb0ef41Sopenharmony_ci<li><code>bytesWritten</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Number_type" class="type"><number></a></li> 12701cb0ef41Sopenharmony_ci</ul> 12711cb0ef41Sopenharmony_ci<p>Signals that a <code>bytesWritten</code> number of bytes have been written 12721cb0ef41Sopenharmony_cito <code>readableStreamBYOBRequest.view</code>.</p> 12731cb0ef41Sopenharmony_ci<h5><code>readableStreamBYOBRequest.respondWithNewView(view)</code><span><a class="mark" href="#readablestreambyobrequestrespondwithnewviewview" id="readablestreambyobrequestrespondwithnewviewview">#</a></span><a aria-hidden="true" class="legacy" id="webstreams_readablestreambyobrequest_respondwithnewview_view"></a></h5> 12741cb0ef41Sopenharmony_ci<div class="api_metadata"> 12751cb0ef41Sopenharmony_ci<span>Added in: v16.5.0</span> 12761cb0ef41Sopenharmony_ci</div> 12771cb0ef41Sopenharmony_ci<ul> 12781cb0ef41Sopenharmony_ci<li><code>view</code> <a href="buffer.html#class-buffer" class="type"><Buffer></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/TypedArray" class="type"><TypedArray></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/DataView" class="type"><DataView></a></li> 12791cb0ef41Sopenharmony_ci</ul> 12801cb0ef41Sopenharmony_ci<p>Signals that the request has been fulfilled with bytes written 12811cb0ef41Sopenharmony_cito a new <code>Buffer</code>, <code>TypedArray</code>, or <code>DataView</code>.</p> 12821cb0ef41Sopenharmony_ci<h5><code>readableStreamBYOBRequest.view</code><span><a class="mark" href="#readablestreambyobrequestview" id="readablestreambyobrequestview">#</a></span><a aria-hidden="true" class="legacy" id="webstreams_readablestreambyobrequest_view"></a></h5> 12831cb0ef41Sopenharmony_ci<div class="api_metadata"> 12841cb0ef41Sopenharmony_ci<span>Added in: v16.5.0</span> 12851cb0ef41Sopenharmony_ci</div> 12861cb0ef41Sopenharmony_ci<ul> 12871cb0ef41Sopenharmony_ci<li>Type: <a href="buffer.html#class-buffer" class="type"><Buffer></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/TypedArray" class="type"><TypedArray></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/DataView" class="type"><DataView></a></li> 12881cb0ef41Sopenharmony_ci</ul> 12891cb0ef41Sopenharmony_ci<h4>Class: <code>WritableStream</code><span><a class="mark" href="#class-writablestream" id="class-writablestream">#</a></span><a aria-hidden="true" class="legacy" id="webstreams_class_writablestream"></a></h4> 12901cb0ef41Sopenharmony_ci<div class="api_metadata"> 12911cb0ef41Sopenharmony_ci<details class="changelog"><summary>History</summary> 12921cb0ef41Sopenharmony_ci<table> 12931cb0ef41Sopenharmony_ci<tbody><tr><th>Version</th><th>Changes</th></tr> 12941cb0ef41Sopenharmony_ci<tr><td>v18.0.0</td> 12951cb0ef41Sopenharmony_ci<td><p>This class is now exposed on the global object.</p></td></tr> 12961cb0ef41Sopenharmony_ci<tr><td>v16.5.0</td> 12971cb0ef41Sopenharmony_ci<td><p><span>Added in: v16.5.0</span></p></td></tr> 12981cb0ef41Sopenharmony_ci</tbody></table> 12991cb0ef41Sopenharmony_ci</details> 13001cb0ef41Sopenharmony_ci</div> 13011cb0ef41Sopenharmony_ci<p>The <code>WritableStream</code> is a destination to which stream data is sent.</p> 13021cb0ef41Sopenharmony_ci<pre><code class="language-js mjs"><span class="hljs-keyword">import</span> { 13031cb0ef41Sopenharmony_ci <span class="hljs-title class_">WritableStream</span>, 13041cb0ef41Sopenharmony_ci} <span class="hljs-keyword">from</span> <span class="hljs-string">'node:stream/web'</span>; 13051cb0ef41Sopenharmony_ci 13061cb0ef41Sopenharmony_ci<span class="hljs-keyword">const</span> stream = <span class="hljs-keyword">new</span> <span class="hljs-title class_">WritableStream</span>({ 13071cb0ef41Sopenharmony_ci <span class="hljs-title function_">write</span>(<span class="hljs-params">chunk</span>) { 13081cb0ef41Sopenharmony_ci <span class="hljs-variable language_">console</span>.<span class="hljs-title function_">log</span>(chunk); 13091cb0ef41Sopenharmony_ci }, 13101cb0ef41Sopenharmony_ci}); 13111cb0ef41Sopenharmony_ci 13121cb0ef41Sopenharmony_ci<span class="hljs-keyword">await</span> stream.<span class="hljs-title function_">getWriter</span>().<span class="hljs-title function_">write</span>(<span class="hljs-string">'Hello World'</span>);</code> <button class="copy-button">copy</button></pre> 13131cb0ef41Sopenharmony_ci<h5><code>new WritableStream([underlyingSink[, strategy]])</code><span><a class="mark" href="#new-writablestreamunderlyingsink-strategy" id="new-writablestreamunderlyingsink-strategy">#</a></span><a aria-hidden="true" class="legacy" id="webstreams_new_writablestream_underlyingsink_strategy"></a></h5> 13141cb0ef41Sopenharmony_ci<div class="api_metadata"> 13151cb0ef41Sopenharmony_ci<span>Added in: v16.5.0</span> 13161cb0ef41Sopenharmony_ci</div> 13171cb0ef41Sopenharmony_ci<ul> 13181cb0ef41Sopenharmony_ci<li><code>underlyingSink</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object" class="type"><Object></a> 13191cb0ef41Sopenharmony_ci<ul> 13201cb0ef41Sopenharmony_ci<li><code>start</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Function" class="type"><Function></a> A user-defined function that is invoked immediately when 13211cb0ef41Sopenharmony_cithe <code>WritableStream</code> is created. 13221cb0ef41Sopenharmony_ci<ul> 13231cb0ef41Sopenharmony_ci<li><code>controller</code> <a href="webstreams.html#class-writablestreamdefaultcontroller" class="type"><WritableStreamDefaultController></a></li> 13241cb0ef41Sopenharmony_ci<li>Returns: <code>undefined</code> or a promise fulfilled with <code>undefined</code>.</li> 13251cb0ef41Sopenharmony_ci</ul> 13261cb0ef41Sopenharmony_ci</li> 13271cb0ef41Sopenharmony_ci<li><code>write</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Function" class="type"><Function></a> A user-defined function that is invoked when a chunk of 13281cb0ef41Sopenharmony_cidata has been written to the <code>WritableStream</code>. 13291cb0ef41Sopenharmony_ci<ul> 13301cb0ef41Sopenharmony_ci<li><code>chunk</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Data_types" class="type"><any></a></li> 13311cb0ef41Sopenharmony_ci<li><code>controller</code> <a href="webstreams.html#class-writablestreamdefaultcontroller" class="type"><WritableStreamDefaultController></a></li> 13321cb0ef41Sopenharmony_ci<li>Returns: A promise fulfilled with <code>undefined</code>.</li> 13331cb0ef41Sopenharmony_ci</ul> 13341cb0ef41Sopenharmony_ci</li> 13351cb0ef41Sopenharmony_ci<li><code>close</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Function" class="type"><Function></a> A user-defined function that is called when the 13361cb0ef41Sopenharmony_ci<code>WritableStream</code> is closed. 13371cb0ef41Sopenharmony_ci<ul> 13381cb0ef41Sopenharmony_ci<li>Returns: A promise fulfilled with <code>undefined</code>.</li> 13391cb0ef41Sopenharmony_ci</ul> 13401cb0ef41Sopenharmony_ci</li> 13411cb0ef41Sopenharmony_ci<li><code>abort</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Function" class="type"><Function></a> A user-defined function that is called to abruptly close 13421cb0ef41Sopenharmony_cithe <code>WritableStream</code>. 13431cb0ef41Sopenharmony_ci<ul> 13441cb0ef41Sopenharmony_ci<li><code>reason</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Data_types" class="type"><any></a></li> 13451cb0ef41Sopenharmony_ci<li>Returns: A promise fulfilled with <code>undefined</code>.</li> 13461cb0ef41Sopenharmony_ci</ul> 13471cb0ef41Sopenharmony_ci</li> 13481cb0ef41Sopenharmony_ci<li><code>type</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Data_types" class="type"><any></a> The <code>type</code> option is reserved for future use and <em>must</em> be 13491cb0ef41Sopenharmony_ciundefined.</li> 13501cb0ef41Sopenharmony_ci</ul> 13511cb0ef41Sopenharmony_ci</li> 13521cb0ef41Sopenharmony_ci<li><code>strategy</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object" class="type"><Object></a> 13531cb0ef41Sopenharmony_ci<ul> 13541cb0ef41Sopenharmony_ci<li><code>highWaterMark</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Number_type" class="type"><number></a> The maximum internal queue size before backpressure 13551cb0ef41Sopenharmony_ciis applied.</li> 13561cb0ef41Sopenharmony_ci<li><code>size</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Function" class="type"><Function></a> A user-defined function used to identify the size of each 13571cb0ef41Sopenharmony_cichunk of data. 13581cb0ef41Sopenharmony_ci<ul> 13591cb0ef41Sopenharmony_ci<li><code>chunk</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Data_types" class="type"><any></a></li> 13601cb0ef41Sopenharmony_ci<li>Returns: <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Number_type" class="type"><number></a></li> 13611cb0ef41Sopenharmony_ci</ul> 13621cb0ef41Sopenharmony_ci</li> 13631cb0ef41Sopenharmony_ci</ul> 13641cb0ef41Sopenharmony_ci</li> 13651cb0ef41Sopenharmony_ci</ul> 13661cb0ef41Sopenharmony_ci<h5><code>writableStream.abort([reason])</code><span><a class="mark" href="#writablestreamabortreason" id="writablestreamabortreason">#</a></span><a aria-hidden="true" class="legacy" id="webstreams_writablestream_abort_reason"></a></h5> 13671cb0ef41Sopenharmony_ci<div class="api_metadata"> 13681cb0ef41Sopenharmony_ci<span>Added in: v16.5.0</span> 13691cb0ef41Sopenharmony_ci</div> 13701cb0ef41Sopenharmony_ci<ul> 13711cb0ef41Sopenharmony_ci<li><code>reason</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Data_types" class="type"><any></a></li> 13721cb0ef41Sopenharmony_ci<li>Returns: A promise fulfilled with <code>undefined</code>.</li> 13731cb0ef41Sopenharmony_ci</ul> 13741cb0ef41Sopenharmony_ci<p>Abruptly terminates the <code>WritableStream</code>. All queued writes will be 13751cb0ef41Sopenharmony_cicanceled with their associated promises rejected.</p> 13761cb0ef41Sopenharmony_ci<h5><code>writableStream.close()</code><span><a class="mark" href="#writablestreamclose" id="writablestreamclose">#</a></span><a aria-hidden="true" class="legacy" id="webstreams_writablestream_close"></a></h5> 13771cb0ef41Sopenharmony_ci<div class="api_metadata"> 13781cb0ef41Sopenharmony_ci<span>Added in: v16.5.0</span> 13791cb0ef41Sopenharmony_ci</div> 13801cb0ef41Sopenharmony_ci<ul> 13811cb0ef41Sopenharmony_ci<li>Returns: A promise fulfilled with <code>undefined</code>.</li> 13821cb0ef41Sopenharmony_ci</ul> 13831cb0ef41Sopenharmony_ci<p>Closes the <code>WritableStream</code> when no additional writes are expected.</p> 13841cb0ef41Sopenharmony_ci<h5><code>writableStream.getWriter()</code><span><a class="mark" href="#writablestreamgetwriter" id="writablestreamgetwriter">#</a></span><a aria-hidden="true" class="legacy" id="webstreams_writablestream_getwriter"></a></h5> 13851cb0ef41Sopenharmony_ci<div class="api_metadata"> 13861cb0ef41Sopenharmony_ci<span>Added in: v16.5.0</span> 13871cb0ef41Sopenharmony_ci</div> 13881cb0ef41Sopenharmony_ci<ul> 13891cb0ef41Sopenharmony_ci<li>Returns: <a href="webstreams.html#class-writablestreamdefaultwriter" class="type"><WritableStreamDefaultWriter></a></li> 13901cb0ef41Sopenharmony_ci</ul> 13911cb0ef41Sopenharmony_ci<p>Creates and returns a new writer instance that can be used to write 13921cb0ef41Sopenharmony_cidata into the <code>WritableStream</code>.</p> 13931cb0ef41Sopenharmony_ci<h5><code>writableStream.locked</code><span><a class="mark" href="#writablestreamlocked" id="writablestreamlocked">#</a></span><a aria-hidden="true" class="legacy" id="webstreams_writablestream_locked"></a></h5> 13941cb0ef41Sopenharmony_ci<div class="api_metadata"> 13951cb0ef41Sopenharmony_ci<span>Added in: v16.5.0</span> 13961cb0ef41Sopenharmony_ci</div> 13971cb0ef41Sopenharmony_ci<ul> 13981cb0ef41Sopenharmony_ci<li>Type: <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Boolean_type" class="type"><boolean></a></li> 13991cb0ef41Sopenharmony_ci</ul> 14001cb0ef41Sopenharmony_ci<p>The <code>writableStream.locked</code> property is <code>false</code> by default, and is 14011cb0ef41Sopenharmony_ciswitched to <code>true</code> while there is an active writer attached to this 14021cb0ef41Sopenharmony_ci<code>WritableStream</code>.</p> 14031cb0ef41Sopenharmony_ci<h5>Transferring with postMessage()<span><a class="mark" href="#transferring-with-postmessage_1" id="transferring-with-postmessage_1">#</a></span><a aria-hidden="true" class="legacy" id="webstreams_transferring_with_postmessage_1"></a></h5> 14041cb0ef41Sopenharmony_ci<p>A <a href="webstreams.html#class-writablestream" class="type"><WritableStream></a> instance can be transferred using a <a href="worker_threads.html#class-messageport" class="type"><MessagePort></a>.</p> 14051cb0ef41Sopenharmony_ci<pre><code class="language-js"><span class="hljs-keyword">const</span> stream = <span class="hljs-keyword">new</span> <span class="hljs-title class_">WritableStream</span>(<span class="hljs-title function_">getWritableSinkSomehow</span>()); 14061cb0ef41Sopenharmony_ci 14071cb0ef41Sopenharmony_ci<span class="hljs-keyword">const</span> { port1, port2 } = <span class="hljs-keyword">new</span> <span class="hljs-title class_">MessageChannel</span>(); 14081cb0ef41Sopenharmony_ci 14091cb0ef41Sopenharmony_ciport1.<span class="hljs-property">onmessage</span> = <span class="hljs-function">(<span class="hljs-params">{ data }</span>) =></span> { 14101cb0ef41Sopenharmony_ci data.<span class="hljs-title function_">getWriter</span>().<span class="hljs-title function_">write</span>(<span class="hljs-string">'hello'</span>); 14111cb0ef41Sopenharmony_ci}; 14121cb0ef41Sopenharmony_ci 14131cb0ef41Sopenharmony_ciport2.<span class="hljs-title function_">postMessage</span>(stream, [stream]);</code> <button class="copy-button">copy</button></pre> 14141cb0ef41Sopenharmony_ci<h4>Class: <code>WritableStreamDefaultWriter</code><span><a class="mark" href="#class-writablestreamdefaultwriter" id="class-writablestreamdefaultwriter">#</a></span><a aria-hidden="true" class="legacy" id="webstreams_class_writablestreamdefaultwriter"></a></h4> 14151cb0ef41Sopenharmony_ci<div class="api_metadata"> 14161cb0ef41Sopenharmony_ci<details class="changelog"><summary>History</summary> 14171cb0ef41Sopenharmony_ci<table> 14181cb0ef41Sopenharmony_ci<tbody><tr><th>Version</th><th>Changes</th></tr> 14191cb0ef41Sopenharmony_ci<tr><td>v18.0.0</td> 14201cb0ef41Sopenharmony_ci<td><p>This class is now exposed on the global object.</p></td></tr> 14211cb0ef41Sopenharmony_ci<tr><td>v16.5.0</td> 14221cb0ef41Sopenharmony_ci<td><p><span>Added in: v16.5.0</span></p></td></tr> 14231cb0ef41Sopenharmony_ci</tbody></table> 14241cb0ef41Sopenharmony_ci</details> 14251cb0ef41Sopenharmony_ci</div> 14261cb0ef41Sopenharmony_ci<h5><code>new WritableStreamDefaultWriter(stream)</code><span><a class="mark" href="#new-writablestreamdefaultwriterstream" id="new-writablestreamdefaultwriterstream">#</a></span><a aria-hidden="true" class="legacy" id="webstreams_new_writablestreamdefaultwriter_stream"></a></h5> 14271cb0ef41Sopenharmony_ci<div class="api_metadata"> 14281cb0ef41Sopenharmony_ci<span>Added in: v16.5.0</span> 14291cb0ef41Sopenharmony_ci</div> 14301cb0ef41Sopenharmony_ci<ul> 14311cb0ef41Sopenharmony_ci<li><code>stream</code> <a href="webstreams.html#class-writablestream" class="type"><WritableStream></a></li> 14321cb0ef41Sopenharmony_ci</ul> 14331cb0ef41Sopenharmony_ci<p>Creates a new <code>WritableStreamDefaultWriter</code> that is locked to the given 14341cb0ef41Sopenharmony_ci<code>WritableStream</code>.</p> 14351cb0ef41Sopenharmony_ci<h5><code>writableStreamDefaultWriter.abort([reason])</code><span><a class="mark" href="#writablestreamdefaultwriterabortreason" id="writablestreamdefaultwriterabortreason">#</a></span><a aria-hidden="true" class="legacy" id="webstreams_writablestreamdefaultwriter_abort_reason"></a></h5> 14361cb0ef41Sopenharmony_ci<div class="api_metadata"> 14371cb0ef41Sopenharmony_ci<span>Added in: v16.5.0</span> 14381cb0ef41Sopenharmony_ci</div> 14391cb0ef41Sopenharmony_ci<ul> 14401cb0ef41Sopenharmony_ci<li><code>reason</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Data_types" class="type"><any></a></li> 14411cb0ef41Sopenharmony_ci<li>Returns: A promise fulfilled with <code>undefined</code>.</li> 14421cb0ef41Sopenharmony_ci</ul> 14431cb0ef41Sopenharmony_ci<p>Abruptly terminates the <code>WritableStream</code>. All queued writes will be 14441cb0ef41Sopenharmony_cicanceled with their associated promises rejected.</p> 14451cb0ef41Sopenharmony_ci<h5><code>writableStreamDefaultWriter.close()</code><span><a class="mark" href="#writablestreamdefaultwriterclose" id="writablestreamdefaultwriterclose">#</a></span><a aria-hidden="true" class="legacy" id="webstreams_writablestreamdefaultwriter_close"></a></h5> 14461cb0ef41Sopenharmony_ci<div class="api_metadata"> 14471cb0ef41Sopenharmony_ci<span>Added in: v16.5.0</span> 14481cb0ef41Sopenharmony_ci</div> 14491cb0ef41Sopenharmony_ci<ul> 14501cb0ef41Sopenharmony_ci<li>Returns: A promise fulfilled with <code>undefined</code>.</li> 14511cb0ef41Sopenharmony_ci</ul> 14521cb0ef41Sopenharmony_ci<p>Closes the <code>WritableStream</code> when no additional writes are expected.</p> 14531cb0ef41Sopenharmony_ci<h5><code>writableStreamDefaultWriter.closed</code><span><a class="mark" href="#writablestreamdefaultwriterclosed" id="writablestreamdefaultwriterclosed">#</a></span><a aria-hidden="true" class="legacy" id="webstreams_writablestreamdefaultwriter_closed"></a></h5> 14541cb0ef41Sopenharmony_ci<div class="api_metadata"> 14551cb0ef41Sopenharmony_ci<span>Added in: v16.5.0</span> 14561cb0ef41Sopenharmony_ci</div> 14571cb0ef41Sopenharmony_ci<ul> 14581cb0ef41Sopenharmony_ci<li>Type: <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Promise" class="type"><Promise></a> Fulfilled with <code>undefined</code> when the associated 14591cb0ef41Sopenharmony_ci<a href="webstreams.html#class-writablestream" class="type"><WritableStream></a> is closed or rejected if the stream errors or the writer's 14601cb0ef41Sopenharmony_cilock is released before the stream finishes closing.</li> 14611cb0ef41Sopenharmony_ci</ul> 14621cb0ef41Sopenharmony_ci<h5><code>writableStreamDefaultWriter.desiredSize</code><span><a class="mark" href="#writablestreamdefaultwriterdesiredsize" id="writablestreamdefaultwriterdesiredsize">#</a></span><a aria-hidden="true" class="legacy" id="webstreams_writablestreamdefaultwriter_desiredsize"></a></h5> 14631cb0ef41Sopenharmony_ci<div class="api_metadata"> 14641cb0ef41Sopenharmony_ci<span>Added in: v16.5.0</span> 14651cb0ef41Sopenharmony_ci</div> 14661cb0ef41Sopenharmony_ci<ul> 14671cb0ef41Sopenharmony_ci<li>Type: <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Number_type" class="type"><number></a></li> 14681cb0ef41Sopenharmony_ci</ul> 14691cb0ef41Sopenharmony_ci<p>The amount of data required to fill the <a href="webstreams.html#class-writablestream" class="type"><WritableStream></a>'s queue.</p> 14701cb0ef41Sopenharmony_ci<h5><code>writableStreamDefaultWriter.ready</code><span><a class="mark" href="#writablestreamdefaultwriterready" id="writablestreamdefaultwriterready">#</a></span><a aria-hidden="true" class="legacy" id="webstreams_writablestreamdefaultwriter_ready"></a></h5> 14711cb0ef41Sopenharmony_ci<div class="api_metadata"> 14721cb0ef41Sopenharmony_ci<span>Added in: v16.5.0</span> 14731cb0ef41Sopenharmony_ci</div> 14741cb0ef41Sopenharmony_ci<ul> 14751cb0ef41Sopenharmony_ci<li>Type: <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Promise" class="type"><Promise></a> Fulfilled with <code>undefined</code> when the writer is ready 14761cb0ef41Sopenharmony_cito be used.</li> 14771cb0ef41Sopenharmony_ci</ul> 14781cb0ef41Sopenharmony_ci<h5><code>writableStreamDefaultWriter.releaseLock()</code><span><a class="mark" href="#writablestreamdefaultwriterreleaselock" id="writablestreamdefaultwriterreleaselock">#</a></span><a aria-hidden="true" class="legacy" id="webstreams_writablestreamdefaultwriter_releaselock"></a></h5> 14791cb0ef41Sopenharmony_ci<div class="api_metadata"> 14801cb0ef41Sopenharmony_ci<span>Added in: v16.5.0</span> 14811cb0ef41Sopenharmony_ci</div> 14821cb0ef41Sopenharmony_ci<p>Releases this writer's lock on the underlying <a href="webstreams.html#class-readablestream" class="type"><ReadableStream></a>.</p> 14831cb0ef41Sopenharmony_ci<h5><code>writableStreamDefaultWriter.write([chunk])</code><span><a class="mark" href="#writablestreamdefaultwriterwritechunk" id="writablestreamdefaultwriterwritechunk">#</a></span><a aria-hidden="true" class="legacy" id="webstreams_writablestreamdefaultwriter_write_chunk"></a></h5> 14841cb0ef41Sopenharmony_ci<div class="api_metadata"> 14851cb0ef41Sopenharmony_ci<span>Added in: v16.5.0</span> 14861cb0ef41Sopenharmony_ci</div> 14871cb0ef41Sopenharmony_ci<ul> 14881cb0ef41Sopenharmony_ci<li><code>chunk</code>: <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Data_types" class="type"><any></a></li> 14891cb0ef41Sopenharmony_ci<li>Returns: A promise fulfilled with <code>undefined</code>.</li> 14901cb0ef41Sopenharmony_ci</ul> 14911cb0ef41Sopenharmony_ci<p>Appends a new chunk of data to the <a href="webstreams.html#class-writablestream" class="type"><WritableStream></a>'s queue.</p> 14921cb0ef41Sopenharmony_ci<h4>Class: <code>WritableStreamDefaultController</code><span><a class="mark" href="#class-writablestreamdefaultcontroller" id="class-writablestreamdefaultcontroller">#</a></span><a aria-hidden="true" class="legacy" id="webstreams_class_writablestreamdefaultcontroller"></a></h4> 14931cb0ef41Sopenharmony_ci<div class="api_metadata"> 14941cb0ef41Sopenharmony_ci<details class="changelog"><summary>History</summary> 14951cb0ef41Sopenharmony_ci<table> 14961cb0ef41Sopenharmony_ci<tbody><tr><th>Version</th><th>Changes</th></tr> 14971cb0ef41Sopenharmony_ci<tr><td>v18.0.0</td> 14981cb0ef41Sopenharmony_ci<td><p>This class is now exposed on the global object.</p></td></tr> 14991cb0ef41Sopenharmony_ci<tr><td>v16.5.0</td> 15001cb0ef41Sopenharmony_ci<td><p><span>Added in: v16.5.0</span></p></td></tr> 15011cb0ef41Sopenharmony_ci</tbody></table> 15021cb0ef41Sopenharmony_ci</details> 15031cb0ef41Sopenharmony_ci</div> 15041cb0ef41Sopenharmony_ci<p>The <code>WritableStreamDefaultController</code> manage's the <a href="webstreams.html#class-writablestream" class="type"><WritableStream></a>'s 15051cb0ef41Sopenharmony_ciinternal state.</p> 15061cb0ef41Sopenharmony_ci<h5><code>writableStreamDefaultController.error([error])</code><span><a class="mark" href="#writablestreamdefaultcontrollererrorerror" id="writablestreamdefaultcontrollererrorerror">#</a></span><a aria-hidden="true" class="legacy" id="webstreams_writablestreamdefaultcontroller_error_error"></a></h5> 15071cb0ef41Sopenharmony_ci<div class="api_metadata"> 15081cb0ef41Sopenharmony_ci<span>Added in: v16.5.0</span> 15091cb0ef41Sopenharmony_ci</div> 15101cb0ef41Sopenharmony_ci<ul> 15111cb0ef41Sopenharmony_ci<li><code>error</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Data_types" class="type"><any></a></li> 15121cb0ef41Sopenharmony_ci</ul> 15131cb0ef41Sopenharmony_ci<p>Called by user-code to signal that an error has occurred while processing 15141cb0ef41Sopenharmony_cithe <code>WritableStream</code> data. When called, the <a href="webstreams.html#class-writablestream" class="type"><WritableStream></a> will be aborted, 15151cb0ef41Sopenharmony_ciwith currently pending writes canceled.</p> 15161cb0ef41Sopenharmony_ci<h5><code>writableStreamDefaultController.signal</code><span><a class="mark" href="#writablestreamdefaultcontrollersignal" id="writablestreamdefaultcontrollersignal">#</a></span><a aria-hidden="true" class="legacy" id="webstreams_writablestreamdefaultcontroller_signal"></a></h5> 15171cb0ef41Sopenharmony_ci<ul> 15181cb0ef41Sopenharmony_ci<li>Type: <a href="globals.html#class-abortsignal" class="type"><AbortSignal></a> An <code>AbortSignal</code> that can be used to cancel pending 15191cb0ef41Sopenharmony_ciwrite or close operations when a <a href="webstreams.html#class-writablestream" class="type"><WritableStream></a> is aborted.</li> 15201cb0ef41Sopenharmony_ci</ul> 15211cb0ef41Sopenharmony_ci<h4>Class: <code>TransformStream</code><span><a class="mark" href="#class-transformstream" id="class-transformstream">#</a></span><a aria-hidden="true" class="legacy" id="webstreams_class_transformstream"></a></h4> 15221cb0ef41Sopenharmony_ci<div class="api_metadata"> 15231cb0ef41Sopenharmony_ci<details class="changelog"><summary>History</summary> 15241cb0ef41Sopenharmony_ci<table> 15251cb0ef41Sopenharmony_ci<tbody><tr><th>Version</th><th>Changes</th></tr> 15261cb0ef41Sopenharmony_ci<tr><td>v18.0.0</td> 15271cb0ef41Sopenharmony_ci<td><p>This class is now exposed on the global object.</p></td></tr> 15281cb0ef41Sopenharmony_ci<tr><td>v16.5.0</td> 15291cb0ef41Sopenharmony_ci<td><p><span>Added in: v16.5.0</span></p></td></tr> 15301cb0ef41Sopenharmony_ci</tbody></table> 15311cb0ef41Sopenharmony_ci</details> 15321cb0ef41Sopenharmony_ci</div> 15331cb0ef41Sopenharmony_ci<p>A <code>TransformStream</code> consists of a <a href="webstreams.html#class-readablestream" class="type"><ReadableStream></a> and a <a href="webstreams.html#class-writablestream" class="type"><WritableStream></a> that 15341cb0ef41Sopenharmony_ciare connected such that the data written to the <code>WritableStream</code> is received, 15351cb0ef41Sopenharmony_ciand potentially transformed, before being pushed into the <code>ReadableStream</code>'s 15361cb0ef41Sopenharmony_ciqueue.</p> 15371cb0ef41Sopenharmony_ci<pre><code class="language-js mjs"><span class="hljs-keyword">import</span> { 15381cb0ef41Sopenharmony_ci <span class="hljs-title class_">TransformStream</span>, 15391cb0ef41Sopenharmony_ci} <span class="hljs-keyword">from</span> <span class="hljs-string">'node:stream/web'</span>; 15401cb0ef41Sopenharmony_ci 15411cb0ef41Sopenharmony_ci<span class="hljs-keyword">const</span> transform = <span class="hljs-keyword">new</span> <span class="hljs-title class_">TransformStream</span>({ 15421cb0ef41Sopenharmony_ci <span class="hljs-title function_">transform</span>(<span class="hljs-params">chunk, controller</span>) { 15431cb0ef41Sopenharmony_ci controller.<span class="hljs-title function_">enqueue</span>(chunk.<span class="hljs-title function_">toUpperCase</span>()); 15441cb0ef41Sopenharmony_ci }, 15451cb0ef41Sopenharmony_ci}); 15461cb0ef41Sopenharmony_ci 15471cb0ef41Sopenharmony_ci<span class="hljs-keyword">await</span> <span class="hljs-title class_">Promise</span>.<span class="hljs-title function_">all</span>([ 15481cb0ef41Sopenharmony_ci transform.<span class="hljs-property">writable</span>.<span class="hljs-title function_">getWriter</span>().<span class="hljs-title function_">write</span>(<span class="hljs-string">'A'</span>), 15491cb0ef41Sopenharmony_ci transform.<span class="hljs-property">readable</span>.<span class="hljs-title function_">getReader</span>().<span class="hljs-title function_">read</span>(), 15501cb0ef41Sopenharmony_ci]);</code> <button class="copy-button">copy</button></pre> 15511cb0ef41Sopenharmony_ci<h5><code>new TransformStream([transformer[, writableStrategy[, readableStrategy]]])</code><span><a class="mark" href="#new-transformstreamtransformer-writablestrategy-readablestrategy" id="new-transformstreamtransformer-writablestrategy-readablestrategy">#</a></span><a aria-hidden="true" class="legacy" id="webstreams_new_transformstream_transformer_writablestrategy_readablestrategy"></a></h5> 15521cb0ef41Sopenharmony_ci<div class="api_metadata"> 15531cb0ef41Sopenharmony_ci<span>Added in: v16.5.0</span> 15541cb0ef41Sopenharmony_ci</div> 15551cb0ef41Sopenharmony_ci<ul> 15561cb0ef41Sopenharmony_ci<li><code>transformer</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object" class="type"><Object></a> 15571cb0ef41Sopenharmony_ci<ul> 15581cb0ef41Sopenharmony_ci<li><code>start</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Function" class="type"><Function></a> A user-defined function that is invoked immediately when 15591cb0ef41Sopenharmony_cithe <code>TransformStream</code> is created. 15601cb0ef41Sopenharmony_ci<ul> 15611cb0ef41Sopenharmony_ci<li><code>controller</code> <a href="webstreams.html#class-transformstreamdefaultcontroller" class="type"><TransformStreamDefaultController></a></li> 15621cb0ef41Sopenharmony_ci<li>Returns: <code>undefined</code> or a promise fulfilled with <code>undefined</code></li> 15631cb0ef41Sopenharmony_ci</ul> 15641cb0ef41Sopenharmony_ci</li> 15651cb0ef41Sopenharmony_ci<li><code>transform</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Function" class="type"><Function></a> A user-defined function that receives, and 15661cb0ef41Sopenharmony_cipotentially modifies, a chunk of data written to <code>transformStream.writable</code>, 15671cb0ef41Sopenharmony_cibefore forwarding that on to <code>transformStream.readable</code>. 15681cb0ef41Sopenharmony_ci<ul> 15691cb0ef41Sopenharmony_ci<li><code>chunk</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Data_types" class="type"><any></a></li> 15701cb0ef41Sopenharmony_ci<li><code>controller</code> <a href="webstreams.html#class-transformstreamdefaultcontroller" class="type"><TransformStreamDefaultController></a></li> 15711cb0ef41Sopenharmony_ci<li>Returns: A promise fulfilled with <code>undefined</code>.</li> 15721cb0ef41Sopenharmony_ci</ul> 15731cb0ef41Sopenharmony_ci</li> 15741cb0ef41Sopenharmony_ci<li><code>flush</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Function" class="type"><Function></a> A user-defined function that is called immediately before 15751cb0ef41Sopenharmony_cithe writable side of the <code>TransformStream</code> is closed, signaling the end of 15761cb0ef41Sopenharmony_cithe transformation process. 15771cb0ef41Sopenharmony_ci<ul> 15781cb0ef41Sopenharmony_ci<li><code>controller</code> <a href="webstreams.html#class-transformstreamdefaultcontroller" class="type"><TransformStreamDefaultController></a></li> 15791cb0ef41Sopenharmony_ci<li>Returns: A promise fulfilled with <code>undefined</code>.</li> 15801cb0ef41Sopenharmony_ci</ul> 15811cb0ef41Sopenharmony_ci</li> 15821cb0ef41Sopenharmony_ci<li><code>readableType</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Data_types" class="type"><any></a> the <code>readableType</code> option is reserved for future use 15831cb0ef41Sopenharmony_ciand <em>must</em> be <code>undefined</code>.</li> 15841cb0ef41Sopenharmony_ci<li><code>writableType</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Data_types" class="type"><any></a> the <code>writableType</code> option is reserved for future use 15851cb0ef41Sopenharmony_ciand <em>must</em> be <code>undefined</code>.</li> 15861cb0ef41Sopenharmony_ci</ul> 15871cb0ef41Sopenharmony_ci</li> 15881cb0ef41Sopenharmony_ci<li><code>writableStrategy</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object" class="type"><Object></a> 15891cb0ef41Sopenharmony_ci<ul> 15901cb0ef41Sopenharmony_ci<li><code>highWaterMark</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Number_type" class="type"><number></a> The maximum internal queue size before backpressure 15911cb0ef41Sopenharmony_ciis applied.</li> 15921cb0ef41Sopenharmony_ci<li><code>size</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Function" class="type"><Function></a> A user-defined function used to identify the size of each 15931cb0ef41Sopenharmony_cichunk of data. 15941cb0ef41Sopenharmony_ci<ul> 15951cb0ef41Sopenharmony_ci<li><code>chunk</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Data_types" class="type"><any></a></li> 15961cb0ef41Sopenharmony_ci<li>Returns: <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Number_type" class="type"><number></a></li> 15971cb0ef41Sopenharmony_ci</ul> 15981cb0ef41Sopenharmony_ci</li> 15991cb0ef41Sopenharmony_ci</ul> 16001cb0ef41Sopenharmony_ci</li> 16011cb0ef41Sopenharmony_ci<li><code>readableStrategy</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object" class="type"><Object></a> 16021cb0ef41Sopenharmony_ci<ul> 16031cb0ef41Sopenharmony_ci<li><code>highWaterMark</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Number_type" class="type"><number></a> The maximum internal queue size before backpressure 16041cb0ef41Sopenharmony_ciis applied.</li> 16051cb0ef41Sopenharmony_ci<li><code>size</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Function" class="type"><Function></a> A user-defined function used to identify the size of each 16061cb0ef41Sopenharmony_cichunk of data. 16071cb0ef41Sopenharmony_ci<ul> 16081cb0ef41Sopenharmony_ci<li><code>chunk</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Data_types" class="type"><any></a></li> 16091cb0ef41Sopenharmony_ci<li>Returns: <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Number_type" class="type"><number></a></li> 16101cb0ef41Sopenharmony_ci</ul> 16111cb0ef41Sopenharmony_ci</li> 16121cb0ef41Sopenharmony_ci</ul> 16131cb0ef41Sopenharmony_ci</li> 16141cb0ef41Sopenharmony_ci</ul> 16151cb0ef41Sopenharmony_ci<h5><code>transformStream.readable</code><span><a class="mark" href="#transformstreamreadable" id="transformstreamreadable">#</a></span><a aria-hidden="true" class="legacy" id="webstreams_transformstream_readable"></a></h5> 16161cb0ef41Sopenharmony_ci<div class="api_metadata"> 16171cb0ef41Sopenharmony_ci<span>Added in: v16.5.0</span> 16181cb0ef41Sopenharmony_ci</div> 16191cb0ef41Sopenharmony_ci<ul> 16201cb0ef41Sopenharmony_ci<li>Type: <a href="webstreams.html#class-readablestream" class="type"><ReadableStream></a></li> 16211cb0ef41Sopenharmony_ci</ul> 16221cb0ef41Sopenharmony_ci<h5><code>transformStream.writable</code><span><a class="mark" href="#transformstreamwritable" id="transformstreamwritable">#</a></span><a aria-hidden="true" class="legacy" id="webstreams_transformstream_writable"></a></h5> 16231cb0ef41Sopenharmony_ci<div class="api_metadata"> 16241cb0ef41Sopenharmony_ci<span>Added in: v16.5.0</span> 16251cb0ef41Sopenharmony_ci</div> 16261cb0ef41Sopenharmony_ci<ul> 16271cb0ef41Sopenharmony_ci<li>Type: <a href="webstreams.html#class-writablestream" class="type"><WritableStream></a></li> 16281cb0ef41Sopenharmony_ci</ul> 16291cb0ef41Sopenharmony_ci<h5>Transferring with postMessage()<span><a class="mark" href="#transferring-with-postmessage_2" id="transferring-with-postmessage_2">#</a></span><a aria-hidden="true" class="legacy" id="webstreams_transferring_with_postmessage_2"></a></h5> 16301cb0ef41Sopenharmony_ci<p>A <a href="webstreams.html#class-transformstream" class="type"><TransformStream></a> instance can be transferred using a <a href="worker_threads.html#class-messageport" class="type"><MessagePort></a>.</p> 16311cb0ef41Sopenharmony_ci<pre><code class="language-js"><span class="hljs-keyword">const</span> stream = <span class="hljs-keyword">new</span> <span class="hljs-title class_">TransformStream</span>(); 16321cb0ef41Sopenharmony_ci 16331cb0ef41Sopenharmony_ci<span class="hljs-keyword">const</span> { port1, port2 } = <span class="hljs-keyword">new</span> <span class="hljs-title class_">MessageChannel</span>(); 16341cb0ef41Sopenharmony_ci 16351cb0ef41Sopenharmony_ciport1.<span class="hljs-property">onmessage</span> = <span class="hljs-function">(<span class="hljs-params">{ data }</span>) =></span> { 16361cb0ef41Sopenharmony_ci <span class="hljs-keyword">const</span> { writable, readable } = data; 16371cb0ef41Sopenharmony_ci <span class="hljs-comment">// ...</span> 16381cb0ef41Sopenharmony_ci}; 16391cb0ef41Sopenharmony_ci 16401cb0ef41Sopenharmony_ciport2.<span class="hljs-title function_">postMessage</span>(stream, [stream]);</code> <button class="copy-button">copy</button></pre> 16411cb0ef41Sopenharmony_ci<h4>Class: <code>TransformStreamDefaultController</code><span><a class="mark" href="#class-transformstreamdefaultcontroller" id="class-transformstreamdefaultcontroller">#</a></span><a aria-hidden="true" class="legacy" id="webstreams_class_transformstreamdefaultcontroller"></a></h4> 16421cb0ef41Sopenharmony_ci<div class="api_metadata"> 16431cb0ef41Sopenharmony_ci<details class="changelog"><summary>History</summary> 16441cb0ef41Sopenharmony_ci<table> 16451cb0ef41Sopenharmony_ci<tbody><tr><th>Version</th><th>Changes</th></tr> 16461cb0ef41Sopenharmony_ci<tr><td>v18.0.0</td> 16471cb0ef41Sopenharmony_ci<td><p>This class is now exposed on the global object.</p></td></tr> 16481cb0ef41Sopenharmony_ci<tr><td>v16.5.0</td> 16491cb0ef41Sopenharmony_ci<td><p><span>Added in: v16.5.0</span></p></td></tr> 16501cb0ef41Sopenharmony_ci</tbody></table> 16511cb0ef41Sopenharmony_ci</details> 16521cb0ef41Sopenharmony_ci</div> 16531cb0ef41Sopenharmony_ci<p>The <code>TransformStreamDefaultController</code> manages the internal state 16541cb0ef41Sopenharmony_ciof the <code>TransformStream</code>.</p> 16551cb0ef41Sopenharmony_ci<h5><code>transformStreamDefaultController.desiredSize</code><span><a class="mark" href="#transformstreamdefaultcontrollerdesiredsize" id="transformstreamdefaultcontrollerdesiredsize">#</a></span><a aria-hidden="true" class="legacy" id="webstreams_transformstreamdefaultcontroller_desiredsize"></a></h5> 16561cb0ef41Sopenharmony_ci<div class="api_metadata"> 16571cb0ef41Sopenharmony_ci<span>Added in: v16.5.0</span> 16581cb0ef41Sopenharmony_ci</div> 16591cb0ef41Sopenharmony_ci<ul> 16601cb0ef41Sopenharmony_ci<li>Type: <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Number_type" class="type"><number></a></li> 16611cb0ef41Sopenharmony_ci</ul> 16621cb0ef41Sopenharmony_ci<p>The amount of data required to fill the readable side's queue.</p> 16631cb0ef41Sopenharmony_ci<h5><code>transformStreamDefaultController.enqueue([chunk])</code><span><a class="mark" href="#transformstreamdefaultcontrollerenqueuechunk" id="transformstreamdefaultcontrollerenqueuechunk">#</a></span><a aria-hidden="true" class="legacy" id="webstreams_transformstreamdefaultcontroller_enqueue_chunk"></a></h5> 16641cb0ef41Sopenharmony_ci<div class="api_metadata"> 16651cb0ef41Sopenharmony_ci<span>Added in: v16.5.0</span> 16661cb0ef41Sopenharmony_ci</div> 16671cb0ef41Sopenharmony_ci<ul> 16681cb0ef41Sopenharmony_ci<li><code>chunk</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Data_types" class="type"><any></a></li> 16691cb0ef41Sopenharmony_ci</ul> 16701cb0ef41Sopenharmony_ci<p>Appends a chunk of data to the readable side's queue.</p> 16711cb0ef41Sopenharmony_ci<h5><code>transformStreamDefaultController.error([reason])</code><span><a class="mark" href="#transformstreamdefaultcontrollererrorreason" id="transformstreamdefaultcontrollererrorreason">#</a></span><a aria-hidden="true" class="legacy" id="webstreams_transformstreamdefaultcontroller_error_reason"></a></h5> 16721cb0ef41Sopenharmony_ci<div class="api_metadata"> 16731cb0ef41Sopenharmony_ci<span>Added in: v16.5.0</span> 16741cb0ef41Sopenharmony_ci</div> 16751cb0ef41Sopenharmony_ci<ul> 16761cb0ef41Sopenharmony_ci<li><code>reason</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Data_types" class="type"><any></a></li> 16771cb0ef41Sopenharmony_ci</ul> 16781cb0ef41Sopenharmony_ci<p>Signals to both the readable and writable side that an error has occurred 16791cb0ef41Sopenharmony_ciwhile processing the transform data, causing both sides to be abruptly 16801cb0ef41Sopenharmony_ciclosed.</p> 16811cb0ef41Sopenharmony_ci<h5><code>transformStreamDefaultController.terminate()</code><span><a class="mark" href="#transformstreamdefaultcontrollerterminate" id="transformstreamdefaultcontrollerterminate">#</a></span><a aria-hidden="true" class="legacy" id="webstreams_transformstreamdefaultcontroller_terminate"></a></h5> 16821cb0ef41Sopenharmony_ci<div class="api_metadata"> 16831cb0ef41Sopenharmony_ci<span>Added in: v16.5.0</span> 16841cb0ef41Sopenharmony_ci</div> 16851cb0ef41Sopenharmony_ci<p>Closes the readable side of the transport and causes the writable side 16861cb0ef41Sopenharmony_cito be abruptly closed with an error.</p> 16871cb0ef41Sopenharmony_ci<h4>Class: <code>ByteLengthQueuingStrategy</code><span><a class="mark" href="#class-bytelengthqueuingstrategy" id="class-bytelengthqueuingstrategy">#</a></span><a aria-hidden="true" class="legacy" id="webstreams_class_bytelengthqueuingstrategy"></a></h4> 16881cb0ef41Sopenharmony_ci<div class="api_metadata"> 16891cb0ef41Sopenharmony_ci<details class="changelog"><summary>History</summary> 16901cb0ef41Sopenharmony_ci<table> 16911cb0ef41Sopenharmony_ci<tbody><tr><th>Version</th><th>Changes</th></tr> 16921cb0ef41Sopenharmony_ci<tr><td>v18.0.0</td> 16931cb0ef41Sopenharmony_ci<td><p>This class is now exposed on the global object.</p></td></tr> 16941cb0ef41Sopenharmony_ci<tr><td>v16.5.0</td> 16951cb0ef41Sopenharmony_ci<td><p><span>Added in: v16.5.0</span></p></td></tr> 16961cb0ef41Sopenharmony_ci</tbody></table> 16971cb0ef41Sopenharmony_ci</details> 16981cb0ef41Sopenharmony_ci</div> 16991cb0ef41Sopenharmony_ci<h5><code>new ByteLengthQueuingStrategy(init)</code><span><a class="mark" href="#new-bytelengthqueuingstrategyinit" id="new-bytelengthqueuingstrategyinit">#</a></span><a aria-hidden="true" class="legacy" id="webstreams_new_bytelengthqueuingstrategy_init"></a></h5> 17001cb0ef41Sopenharmony_ci<div class="api_metadata"> 17011cb0ef41Sopenharmony_ci<span>Added in: v16.5.0</span> 17021cb0ef41Sopenharmony_ci</div> 17031cb0ef41Sopenharmony_ci<ul> 17041cb0ef41Sopenharmony_ci<li><code>init</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object" class="type"><Object></a> 17051cb0ef41Sopenharmony_ci<ul> 17061cb0ef41Sopenharmony_ci<li><code>highWaterMark</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Number_type" class="type"><number></a></li> 17071cb0ef41Sopenharmony_ci</ul> 17081cb0ef41Sopenharmony_ci</li> 17091cb0ef41Sopenharmony_ci</ul> 17101cb0ef41Sopenharmony_ci<h5><code>byteLengthQueuingStrategy.highWaterMark</code><span><a class="mark" href="#bytelengthqueuingstrategyhighwatermark" id="bytelengthqueuingstrategyhighwatermark">#</a></span><a aria-hidden="true" class="legacy" id="webstreams_bytelengthqueuingstrategy_highwatermark"></a></h5> 17111cb0ef41Sopenharmony_ci<div class="api_metadata"> 17121cb0ef41Sopenharmony_ci<span>Added in: v16.5.0</span> 17131cb0ef41Sopenharmony_ci</div> 17141cb0ef41Sopenharmony_ci<ul> 17151cb0ef41Sopenharmony_ci<li>Type: <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Number_type" class="type"><number></a></li> 17161cb0ef41Sopenharmony_ci</ul> 17171cb0ef41Sopenharmony_ci<h5><code>byteLengthQueuingStrategy.size</code><span><a class="mark" href="#bytelengthqueuingstrategysize" id="bytelengthqueuingstrategysize">#</a></span><a aria-hidden="true" class="legacy" id="webstreams_bytelengthqueuingstrategy_size"></a></h5> 17181cb0ef41Sopenharmony_ci<div class="api_metadata"> 17191cb0ef41Sopenharmony_ci<span>Added in: v16.5.0</span> 17201cb0ef41Sopenharmony_ci</div> 17211cb0ef41Sopenharmony_ci<ul> 17221cb0ef41Sopenharmony_ci<li>Type: <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Function" class="type"><Function></a> 17231cb0ef41Sopenharmony_ci<ul> 17241cb0ef41Sopenharmony_ci<li><code>chunk</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Data_types" class="type"><any></a></li> 17251cb0ef41Sopenharmony_ci<li>Returns: <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Number_type" class="type"><number></a></li> 17261cb0ef41Sopenharmony_ci</ul> 17271cb0ef41Sopenharmony_ci</li> 17281cb0ef41Sopenharmony_ci</ul> 17291cb0ef41Sopenharmony_ci<h4>Class: <code>CountQueuingStrategy</code><span><a class="mark" href="#class-countqueuingstrategy" id="class-countqueuingstrategy">#</a></span><a aria-hidden="true" class="legacy" id="webstreams_class_countqueuingstrategy"></a></h4> 17301cb0ef41Sopenharmony_ci<div class="api_metadata"> 17311cb0ef41Sopenharmony_ci<details class="changelog"><summary>History</summary> 17321cb0ef41Sopenharmony_ci<table> 17331cb0ef41Sopenharmony_ci<tbody><tr><th>Version</th><th>Changes</th></tr> 17341cb0ef41Sopenharmony_ci<tr><td>v18.0.0</td> 17351cb0ef41Sopenharmony_ci<td><p>This class is now exposed on the global object.</p></td></tr> 17361cb0ef41Sopenharmony_ci<tr><td>v16.5.0</td> 17371cb0ef41Sopenharmony_ci<td><p><span>Added in: v16.5.0</span></p></td></tr> 17381cb0ef41Sopenharmony_ci</tbody></table> 17391cb0ef41Sopenharmony_ci</details> 17401cb0ef41Sopenharmony_ci</div> 17411cb0ef41Sopenharmony_ci<h5><code>new CountQueuingStrategy(init)</code><span><a class="mark" href="#new-countqueuingstrategyinit" id="new-countqueuingstrategyinit">#</a></span><a aria-hidden="true" class="legacy" id="webstreams_new_countqueuingstrategy_init"></a></h5> 17421cb0ef41Sopenharmony_ci<div class="api_metadata"> 17431cb0ef41Sopenharmony_ci<span>Added in: v16.5.0</span> 17441cb0ef41Sopenharmony_ci</div> 17451cb0ef41Sopenharmony_ci<ul> 17461cb0ef41Sopenharmony_ci<li><code>init</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object" class="type"><Object></a> 17471cb0ef41Sopenharmony_ci<ul> 17481cb0ef41Sopenharmony_ci<li><code>highWaterMark</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Number_type" class="type"><number></a></li> 17491cb0ef41Sopenharmony_ci</ul> 17501cb0ef41Sopenharmony_ci</li> 17511cb0ef41Sopenharmony_ci</ul> 17521cb0ef41Sopenharmony_ci<h5><code>countQueuingStrategy.highWaterMark</code><span><a class="mark" href="#countqueuingstrategyhighwatermark" id="countqueuingstrategyhighwatermark">#</a></span><a aria-hidden="true" class="legacy" id="webstreams_countqueuingstrategy_highwatermark"></a></h5> 17531cb0ef41Sopenharmony_ci<div class="api_metadata"> 17541cb0ef41Sopenharmony_ci<span>Added in: v16.5.0</span> 17551cb0ef41Sopenharmony_ci</div> 17561cb0ef41Sopenharmony_ci<ul> 17571cb0ef41Sopenharmony_ci<li>Type: <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Number_type" class="type"><number></a></li> 17581cb0ef41Sopenharmony_ci</ul> 17591cb0ef41Sopenharmony_ci<h5><code>countQueuingStrategy.size</code><span><a class="mark" href="#countqueuingstrategysize" id="countqueuingstrategysize">#</a></span><a aria-hidden="true" class="legacy" id="webstreams_countqueuingstrategy_size"></a></h5> 17601cb0ef41Sopenharmony_ci<div class="api_metadata"> 17611cb0ef41Sopenharmony_ci<span>Added in: v16.5.0</span> 17621cb0ef41Sopenharmony_ci</div> 17631cb0ef41Sopenharmony_ci<ul> 17641cb0ef41Sopenharmony_ci<li>Type: <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Function" class="type"><Function></a> 17651cb0ef41Sopenharmony_ci<ul> 17661cb0ef41Sopenharmony_ci<li><code>chunk</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Data_types" class="type"><any></a></li> 17671cb0ef41Sopenharmony_ci<li>Returns: <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Number_type" class="type"><number></a></li> 17681cb0ef41Sopenharmony_ci</ul> 17691cb0ef41Sopenharmony_ci</li> 17701cb0ef41Sopenharmony_ci</ul> 17711cb0ef41Sopenharmony_ci<h4>Class: <code>TextEncoderStream</code><span><a class="mark" href="#class-textencoderstream" id="class-textencoderstream">#</a></span><a aria-hidden="true" class="legacy" id="webstreams_class_textencoderstream"></a></h4> 17721cb0ef41Sopenharmony_ci<div class="api_metadata"> 17731cb0ef41Sopenharmony_ci<details class="changelog"><summary>History</summary> 17741cb0ef41Sopenharmony_ci<table> 17751cb0ef41Sopenharmony_ci<tbody><tr><th>Version</th><th>Changes</th></tr> 17761cb0ef41Sopenharmony_ci<tr><td>v18.0.0</td> 17771cb0ef41Sopenharmony_ci<td><p>This class is now exposed on the global object.</p></td></tr> 17781cb0ef41Sopenharmony_ci<tr><td>v16.6.0</td> 17791cb0ef41Sopenharmony_ci<td><p><span>Added in: v16.6.0</span></p></td></tr> 17801cb0ef41Sopenharmony_ci</tbody></table> 17811cb0ef41Sopenharmony_ci</details> 17821cb0ef41Sopenharmony_ci</div> 17831cb0ef41Sopenharmony_ci<h5><code>new TextEncoderStream()</code><span><a class="mark" href="#new-textencoderstream" id="new-textencoderstream">#</a></span><a aria-hidden="true" class="legacy" id="webstreams_new_textencoderstream"></a></h5> 17841cb0ef41Sopenharmony_ci<div class="api_metadata"> 17851cb0ef41Sopenharmony_ci<span>Added in: v16.6.0</span> 17861cb0ef41Sopenharmony_ci</div> 17871cb0ef41Sopenharmony_ci<p>Creates a new <code>TextEncoderStream</code> instance.</p> 17881cb0ef41Sopenharmony_ci<h5><code>textEncoderStream.encoding</code><span><a class="mark" href="#textencoderstreamencoding" id="textencoderstreamencoding">#</a></span><a aria-hidden="true" class="legacy" id="webstreams_textencoderstream_encoding"></a></h5> 17891cb0ef41Sopenharmony_ci<div class="api_metadata"> 17901cb0ef41Sopenharmony_ci<span>Added in: v16.6.0</span> 17911cb0ef41Sopenharmony_ci</div> 17921cb0ef41Sopenharmony_ci<ul> 17931cb0ef41Sopenharmony_ci<li>Type: <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a></li> 17941cb0ef41Sopenharmony_ci</ul> 17951cb0ef41Sopenharmony_ci<p>The encoding supported by the <code>TextEncoderStream</code> instance.</p> 17961cb0ef41Sopenharmony_ci<h5><code>textEncoderStream.readable</code><span><a class="mark" href="#textencoderstreamreadable" id="textencoderstreamreadable">#</a></span><a aria-hidden="true" class="legacy" id="webstreams_textencoderstream_readable"></a></h5> 17971cb0ef41Sopenharmony_ci<div class="api_metadata"> 17981cb0ef41Sopenharmony_ci<span>Added in: v16.6.0</span> 17991cb0ef41Sopenharmony_ci</div> 18001cb0ef41Sopenharmony_ci<ul> 18011cb0ef41Sopenharmony_ci<li>Type: <a href="webstreams.html#class-readablestream" class="type"><ReadableStream></a></li> 18021cb0ef41Sopenharmony_ci</ul> 18031cb0ef41Sopenharmony_ci<h5><code>textEncoderStream.writable</code><span><a class="mark" href="#textencoderstreamwritable" id="textencoderstreamwritable">#</a></span><a aria-hidden="true" class="legacy" id="webstreams_textencoderstream_writable"></a></h5> 18041cb0ef41Sopenharmony_ci<div class="api_metadata"> 18051cb0ef41Sopenharmony_ci<span>Added in: v16.6.0</span> 18061cb0ef41Sopenharmony_ci</div> 18071cb0ef41Sopenharmony_ci<ul> 18081cb0ef41Sopenharmony_ci<li>Type: <a href="webstreams.html#class-writablestream" class="type"><WritableStream></a></li> 18091cb0ef41Sopenharmony_ci</ul> 18101cb0ef41Sopenharmony_ci<h4>Class: <code>TextDecoderStream</code><span><a class="mark" href="#class-textdecoderstream" id="class-textdecoderstream">#</a></span><a aria-hidden="true" class="legacy" id="webstreams_class_textdecoderstream"></a></h4> 18111cb0ef41Sopenharmony_ci<div class="api_metadata"> 18121cb0ef41Sopenharmony_ci<details class="changelog"><summary>History</summary> 18131cb0ef41Sopenharmony_ci<table> 18141cb0ef41Sopenharmony_ci<tbody><tr><th>Version</th><th>Changes</th></tr> 18151cb0ef41Sopenharmony_ci<tr><td>v18.0.0</td> 18161cb0ef41Sopenharmony_ci<td><p>This class is now exposed on the global object.</p></td></tr> 18171cb0ef41Sopenharmony_ci<tr><td>v16.6.0</td> 18181cb0ef41Sopenharmony_ci<td><p><span>Added in: v16.6.0</span></p></td></tr> 18191cb0ef41Sopenharmony_ci</tbody></table> 18201cb0ef41Sopenharmony_ci</details> 18211cb0ef41Sopenharmony_ci</div> 18221cb0ef41Sopenharmony_ci<h5><code>new TextDecoderStream([encoding[, options]])</code><span><a class="mark" href="#new-textdecoderstreamencoding-options" id="new-textdecoderstreamencoding-options">#</a></span><a aria-hidden="true" class="legacy" id="webstreams_new_textdecoderstream_encoding_options"></a></h5> 18231cb0ef41Sopenharmony_ci<div class="api_metadata"> 18241cb0ef41Sopenharmony_ci<span>Added in: v16.6.0</span> 18251cb0ef41Sopenharmony_ci</div> 18261cb0ef41Sopenharmony_ci<ul> 18271cb0ef41Sopenharmony_ci<li><code>encoding</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a> Identifies the <code>encoding</code> that this <code>TextDecoder</code> instance 18281cb0ef41Sopenharmony_cisupports. <strong>Default:</strong> <code>'utf-8'</code>.</li> 18291cb0ef41Sopenharmony_ci<li><code>options</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object" class="type"><Object></a> 18301cb0ef41Sopenharmony_ci<ul> 18311cb0ef41Sopenharmony_ci<li><code>fatal</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Boolean_type" class="type"><boolean></a> <code>true</code> if decoding failures are fatal.</li> 18321cb0ef41Sopenharmony_ci<li><code>ignoreBOM</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Boolean_type" class="type"><boolean></a> When <code>true</code>, the <code>TextDecoderStream</code> will include the 18331cb0ef41Sopenharmony_cibyte order mark in the decoded result. When <code>false</code>, the byte order mark 18341cb0ef41Sopenharmony_ciwill be removed from the output. This option is only used when <code>encoding</code> is 18351cb0ef41Sopenharmony_ci<code>'utf-8'</code>, <code>'utf-16be'</code>, or <code>'utf-16le'</code>. <strong>Default:</strong> <code>false</code>.</li> 18361cb0ef41Sopenharmony_ci</ul> 18371cb0ef41Sopenharmony_ci</li> 18381cb0ef41Sopenharmony_ci</ul> 18391cb0ef41Sopenharmony_ci<p>Creates a new <code>TextDecoderStream</code> instance.</p> 18401cb0ef41Sopenharmony_ci<h5><code>textDecoderStream.encoding</code><span><a class="mark" href="#textdecoderstreamencoding" id="textdecoderstreamencoding">#</a></span><a aria-hidden="true" class="legacy" id="webstreams_textdecoderstream_encoding"></a></h5> 18411cb0ef41Sopenharmony_ci<div class="api_metadata"> 18421cb0ef41Sopenharmony_ci<span>Added in: v16.6.0</span> 18431cb0ef41Sopenharmony_ci</div> 18441cb0ef41Sopenharmony_ci<ul> 18451cb0ef41Sopenharmony_ci<li>Type: <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a></li> 18461cb0ef41Sopenharmony_ci</ul> 18471cb0ef41Sopenharmony_ci<p>The encoding supported by the <code>TextDecoderStream</code> instance.</p> 18481cb0ef41Sopenharmony_ci<h5><code>textDecoderStream.fatal</code><span><a class="mark" href="#textdecoderstreamfatal" id="textdecoderstreamfatal">#</a></span><a aria-hidden="true" class="legacy" id="webstreams_textdecoderstream_fatal"></a></h5> 18491cb0ef41Sopenharmony_ci<div class="api_metadata"> 18501cb0ef41Sopenharmony_ci<span>Added in: v16.6.0</span> 18511cb0ef41Sopenharmony_ci</div> 18521cb0ef41Sopenharmony_ci<ul> 18531cb0ef41Sopenharmony_ci<li>Type: <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Boolean_type" class="type"><boolean></a></li> 18541cb0ef41Sopenharmony_ci</ul> 18551cb0ef41Sopenharmony_ci<p>The value will be <code>true</code> if decoding errors result in a <code>TypeError</code> being 18561cb0ef41Sopenharmony_cithrown.</p> 18571cb0ef41Sopenharmony_ci<h5><code>textDecoderStream.ignoreBOM</code><span><a class="mark" href="#textdecoderstreamignorebom" id="textdecoderstreamignorebom">#</a></span><a aria-hidden="true" class="legacy" id="webstreams_textdecoderstream_ignorebom"></a></h5> 18581cb0ef41Sopenharmony_ci<div class="api_metadata"> 18591cb0ef41Sopenharmony_ci<span>Added in: v16.6.0</span> 18601cb0ef41Sopenharmony_ci</div> 18611cb0ef41Sopenharmony_ci<ul> 18621cb0ef41Sopenharmony_ci<li>Type: <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Boolean_type" class="type"><boolean></a></li> 18631cb0ef41Sopenharmony_ci</ul> 18641cb0ef41Sopenharmony_ci<p>The value will be <code>true</code> if the decoding result will include the byte order 18651cb0ef41Sopenharmony_cimark.</p> 18661cb0ef41Sopenharmony_ci<h5><code>textDecoderStream.readable</code><span><a class="mark" href="#textdecoderstreamreadable" id="textdecoderstreamreadable">#</a></span><a aria-hidden="true" class="legacy" id="webstreams_textdecoderstream_readable"></a></h5> 18671cb0ef41Sopenharmony_ci<div class="api_metadata"> 18681cb0ef41Sopenharmony_ci<span>Added in: v16.6.0</span> 18691cb0ef41Sopenharmony_ci</div> 18701cb0ef41Sopenharmony_ci<ul> 18711cb0ef41Sopenharmony_ci<li>Type: <a href="webstreams.html#class-readablestream" class="type"><ReadableStream></a></li> 18721cb0ef41Sopenharmony_ci</ul> 18731cb0ef41Sopenharmony_ci<h5><code>textDecoderStream.writable</code><span><a class="mark" href="#textdecoderstreamwritable" id="textdecoderstreamwritable">#</a></span><a aria-hidden="true" class="legacy" id="webstreams_textdecoderstream_writable"></a></h5> 18741cb0ef41Sopenharmony_ci<div class="api_metadata"> 18751cb0ef41Sopenharmony_ci<span>Added in: v16.6.0</span> 18761cb0ef41Sopenharmony_ci</div> 18771cb0ef41Sopenharmony_ci<ul> 18781cb0ef41Sopenharmony_ci<li>Type: <a href="webstreams.html#class-writablestream" class="type"><WritableStream></a></li> 18791cb0ef41Sopenharmony_ci</ul> 18801cb0ef41Sopenharmony_ci<h4>Class: <code>CompressionStream</code><span><a class="mark" href="#class-compressionstream" id="class-compressionstream">#</a></span><a aria-hidden="true" class="legacy" id="webstreams_class_compressionstream"></a></h4> 18811cb0ef41Sopenharmony_ci<div class="api_metadata"> 18821cb0ef41Sopenharmony_ci<details class="changelog"><summary>History</summary> 18831cb0ef41Sopenharmony_ci<table> 18841cb0ef41Sopenharmony_ci<tbody><tr><th>Version</th><th>Changes</th></tr> 18851cb0ef41Sopenharmony_ci<tr><td>v18.0.0</td> 18861cb0ef41Sopenharmony_ci<td><p>This class is now exposed on the global object.</p></td></tr> 18871cb0ef41Sopenharmony_ci<tr><td>v17.0.0</td> 18881cb0ef41Sopenharmony_ci<td><p><span>Added in: v17.0.0</span></p></td></tr> 18891cb0ef41Sopenharmony_ci</tbody></table> 18901cb0ef41Sopenharmony_ci</details> 18911cb0ef41Sopenharmony_ci</div> 18921cb0ef41Sopenharmony_ci<h5><code>new CompressionStream(format)</code><span><a class="mark" href="#new-compressionstreamformat" id="new-compressionstreamformat">#</a></span><a aria-hidden="true" class="legacy" id="webstreams_new_compressionstream_format"></a></h5> 18931cb0ef41Sopenharmony_ci<div class="api_metadata"> 18941cb0ef41Sopenharmony_ci<span>Added in: v17.0.0</span> 18951cb0ef41Sopenharmony_ci</div> 18961cb0ef41Sopenharmony_ci<ul> 18971cb0ef41Sopenharmony_ci<li><code>format</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a> One of either <code>'deflate'</code> or <code>'gzip'</code>.</li> 18981cb0ef41Sopenharmony_ci</ul> 18991cb0ef41Sopenharmony_ci<h5><code>compressionStream.readable</code><span><a class="mark" href="#compressionstreamreadable" id="compressionstreamreadable">#</a></span><a aria-hidden="true" class="legacy" id="webstreams_compressionstream_readable"></a></h5> 19001cb0ef41Sopenharmony_ci<div class="api_metadata"> 19011cb0ef41Sopenharmony_ci<span>Added in: v17.0.0</span> 19021cb0ef41Sopenharmony_ci</div> 19031cb0ef41Sopenharmony_ci<ul> 19041cb0ef41Sopenharmony_ci<li>Type: <a href="webstreams.html#class-readablestream" class="type"><ReadableStream></a></li> 19051cb0ef41Sopenharmony_ci</ul> 19061cb0ef41Sopenharmony_ci<h5><code>compressionStream.writable</code><span><a class="mark" href="#compressionstreamwritable" id="compressionstreamwritable">#</a></span><a aria-hidden="true" class="legacy" id="webstreams_compressionstream_writable"></a></h5> 19071cb0ef41Sopenharmony_ci<div class="api_metadata"> 19081cb0ef41Sopenharmony_ci<span>Added in: v17.0.0</span> 19091cb0ef41Sopenharmony_ci</div> 19101cb0ef41Sopenharmony_ci<ul> 19111cb0ef41Sopenharmony_ci<li>Type: <a href="webstreams.html#class-writablestream" class="type"><WritableStream></a></li> 19121cb0ef41Sopenharmony_ci</ul> 19131cb0ef41Sopenharmony_ci<h4>Class: <code>DecompressionStream</code><span><a class="mark" href="#class-decompressionstream" id="class-decompressionstream">#</a></span><a aria-hidden="true" class="legacy" id="webstreams_class_decompressionstream"></a></h4> 19141cb0ef41Sopenharmony_ci<div class="api_metadata"> 19151cb0ef41Sopenharmony_ci<details class="changelog"><summary>History</summary> 19161cb0ef41Sopenharmony_ci<table> 19171cb0ef41Sopenharmony_ci<tbody><tr><th>Version</th><th>Changes</th></tr> 19181cb0ef41Sopenharmony_ci<tr><td>v18.0.0</td> 19191cb0ef41Sopenharmony_ci<td><p>This class is now exposed on the global object.</p></td></tr> 19201cb0ef41Sopenharmony_ci<tr><td>v17.0.0</td> 19211cb0ef41Sopenharmony_ci<td><p><span>Added in: v17.0.0</span></p></td></tr> 19221cb0ef41Sopenharmony_ci</tbody></table> 19231cb0ef41Sopenharmony_ci</details> 19241cb0ef41Sopenharmony_ci</div> 19251cb0ef41Sopenharmony_ci<h5><code>new DecompressionStream(format)</code><span><a class="mark" href="#new-decompressionstreamformat" id="new-decompressionstreamformat">#</a></span><a aria-hidden="true" class="legacy" id="webstreams_new_decompressionstream_format"></a></h5> 19261cb0ef41Sopenharmony_ci<div class="api_metadata"> 19271cb0ef41Sopenharmony_ci<span>Added in: v17.0.0</span> 19281cb0ef41Sopenharmony_ci</div> 19291cb0ef41Sopenharmony_ci<ul> 19301cb0ef41Sopenharmony_ci<li><code>format</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a> One of either <code>'deflate'</code> or <code>'gzip'</code>.</li> 19311cb0ef41Sopenharmony_ci</ul> 19321cb0ef41Sopenharmony_ci<h5><code>decompressionStream.readable</code><span><a class="mark" href="#decompressionstreamreadable" id="decompressionstreamreadable">#</a></span><a aria-hidden="true" class="legacy" id="webstreams_decompressionstream_readable"></a></h5> 19331cb0ef41Sopenharmony_ci<div class="api_metadata"> 19341cb0ef41Sopenharmony_ci<span>Added in: v17.0.0</span> 19351cb0ef41Sopenharmony_ci</div> 19361cb0ef41Sopenharmony_ci<ul> 19371cb0ef41Sopenharmony_ci<li>Type: <a href="webstreams.html#class-readablestream" class="type"><ReadableStream></a></li> 19381cb0ef41Sopenharmony_ci</ul> 19391cb0ef41Sopenharmony_ci<h5><code>decompressionStream.writable</code><span><a class="mark" href="#decompressionstreamwritable" id="decompressionstreamwritable">#</a></span><a aria-hidden="true" class="legacy" id="webstreams_decompressionstream_writable"></a></h5> 19401cb0ef41Sopenharmony_ci<div class="api_metadata"> 19411cb0ef41Sopenharmony_ci<span>Added in: v17.0.0</span> 19421cb0ef41Sopenharmony_ci</div> 19431cb0ef41Sopenharmony_ci<ul> 19441cb0ef41Sopenharmony_ci<li>Type: <a href="webstreams.html#class-writablestream" class="type"><WritableStream></a></li> 19451cb0ef41Sopenharmony_ci</ul> 19461cb0ef41Sopenharmony_ci<h4>Utility Consumers<span><a class="mark" href="#utility-consumers" id="utility-consumers">#</a></span><a aria-hidden="true" class="legacy" id="webstreams_utility_consumers"></a></h4> 19471cb0ef41Sopenharmony_ci<div class="api_metadata"> 19481cb0ef41Sopenharmony_ci<span>Added in: v16.7.0</span> 19491cb0ef41Sopenharmony_ci</div> 19501cb0ef41Sopenharmony_ci<p>The utility consumer functions provide common options for consuming 19511cb0ef41Sopenharmony_cistreams.</p> 19521cb0ef41Sopenharmony_ci<p>They are accessed using:</p> 19531cb0ef41Sopenharmony_ci 19541cb0ef41Sopenharmony_ci<pre class="with-14-chars"><input class="js-flavor-selector" type="checkbox" checked aria-label="Show modern ES modules syntax"><code class="language-js mjs"><span class="hljs-keyword">import</span> { 19551cb0ef41Sopenharmony_ci arrayBuffer, 19561cb0ef41Sopenharmony_ci blob, 19571cb0ef41Sopenharmony_ci buffer, 19581cb0ef41Sopenharmony_ci json, 19591cb0ef41Sopenharmony_ci text, 19601cb0ef41Sopenharmony_ci} <span class="hljs-keyword">from</span> <span class="hljs-string">'node:stream/consumers'</span>;</code><code class="language-js cjs"><span class="hljs-keyword">const</span> { 19611cb0ef41Sopenharmony_ci arrayBuffer, 19621cb0ef41Sopenharmony_ci blob, 19631cb0ef41Sopenharmony_ci buffer, 19641cb0ef41Sopenharmony_ci json, 19651cb0ef41Sopenharmony_ci text, 19661cb0ef41Sopenharmony_ci} = <span class="hljs-built_in">require</span>(<span class="hljs-string">'node:stream/consumers'</span>);</code><button class="copy-button">copy</button></pre> 19671cb0ef41Sopenharmony_ci<h5><code>streamConsumers.arrayBuffer(stream)</code><span><a class="mark" href="#streamconsumersarraybufferstream" id="streamconsumersarraybufferstream">#</a></span><a aria-hidden="true" class="legacy" id="webstreams_streamconsumers_arraybuffer_stream"></a></h5> 19681cb0ef41Sopenharmony_ci<div class="api_metadata"> 19691cb0ef41Sopenharmony_ci<span>Added in: v16.7.0</span> 19701cb0ef41Sopenharmony_ci</div> 19711cb0ef41Sopenharmony_ci<ul> 19721cb0ef41Sopenharmony_ci<li><code>stream</code> <a href="webstreams.html#class-readablestream" class="type"><ReadableStream></a> | <a href="stream.html#class-streamreadable" class="type"><stream.Readable></a> | <a href="https://tc39.github.io/ecma262/#sec-asynciterator-interface" class="type"><AsyncIterator></a></li> 19731cb0ef41Sopenharmony_ci<li>Returns: <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Promise" class="type"><Promise></a> Fulfills with an <code>ArrayBuffer</code> containing the full 19741cb0ef41Sopenharmony_cicontents of the stream.</li> 19751cb0ef41Sopenharmony_ci</ul> 19761cb0ef41Sopenharmony_ci 19771cb0ef41Sopenharmony_ci<pre class="with-57-chars"><input class="js-flavor-selector" type="checkbox" checked aria-label="Show modern ES modules syntax"><code class="language-js mjs"><span class="hljs-keyword">import</span> { arrayBuffer } <span class="hljs-keyword">from</span> <span class="hljs-string">'node:stream/consumers'</span>; 19781cb0ef41Sopenharmony_ci<span class="hljs-keyword">import</span> { <span class="hljs-title class_">Readable</span> } <span class="hljs-keyword">from</span> <span class="hljs-string">'node:stream'</span>; 19791cb0ef41Sopenharmony_ci<span class="hljs-keyword">import</span> { <span class="hljs-title class_">TextEncoder</span> } <span class="hljs-keyword">from</span> <span class="hljs-string">'node:util'</span>; 19801cb0ef41Sopenharmony_ci 19811cb0ef41Sopenharmony_ci<span class="hljs-keyword">const</span> encoder = <span class="hljs-keyword">new</span> <span class="hljs-title class_">TextEncoder</span>(); 19821cb0ef41Sopenharmony_ci<span class="hljs-keyword">const</span> dataArray = encoder.<span class="hljs-title function_">encode</span>(<span class="hljs-string">'hello world from consumers!'</span>); 19831cb0ef41Sopenharmony_ci 19841cb0ef41Sopenharmony_ci<span class="hljs-keyword">const</span> readable = <span class="hljs-title class_">Readable</span>.<span class="hljs-title function_">from</span>(dataArray); 19851cb0ef41Sopenharmony_ci<span class="hljs-keyword">const</span> data = <span class="hljs-keyword">await</span> <span class="hljs-title function_">arrayBuffer</span>(readable); 19861cb0ef41Sopenharmony_ci<span class="hljs-variable language_">console</span>.<span class="hljs-title function_">log</span>(<span class="hljs-string">`from readable: <span class="hljs-subst">${data.byteLength}</span>`</span>);</code><code class="language-js cjs"><span class="hljs-keyword">const</span> { arrayBuffer } = <span class="hljs-built_in">require</span>(<span class="hljs-string">'node:stream/consumers'</span>); 19871cb0ef41Sopenharmony_ci<span class="hljs-keyword">const</span> { <span class="hljs-title class_">Readable</span> } = <span class="hljs-built_in">require</span>(<span class="hljs-string">'node:stream'</span>); 19881cb0ef41Sopenharmony_ci<span class="hljs-keyword">const</span> { <span class="hljs-title class_">TextEncoder</span> } = <span class="hljs-built_in">require</span>(<span class="hljs-string">'node:util'</span>); 19891cb0ef41Sopenharmony_ci 19901cb0ef41Sopenharmony_ci<span class="hljs-keyword">const</span> encoder = <span class="hljs-keyword">new</span> <span class="hljs-title class_">TextEncoder</span>(); 19911cb0ef41Sopenharmony_ci<span class="hljs-keyword">const</span> dataArray = encoder.<span class="hljs-title function_">encode</span>(<span class="hljs-string">'hello world from consumers!'</span>); 19921cb0ef41Sopenharmony_ci<span class="hljs-keyword">const</span> readable = <span class="hljs-title class_">Readable</span>.<span class="hljs-title function_">from</span>(dataArray); 19931cb0ef41Sopenharmony_ci<span class="hljs-title function_">arrayBuffer</span>(readable).<span class="hljs-title function_">then</span>(<span class="hljs-function">(<span class="hljs-params">data</span>) =></span> { 19941cb0ef41Sopenharmony_ci <span class="hljs-variable language_">console</span>.<span class="hljs-title function_">log</span>(<span class="hljs-string">`from readable: <span class="hljs-subst">${data.byteLength}</span>`</span>); 19951cb0ef41Sopenharmony_ci});</code><button class="copy-button">copy</button></pre> 19961cb0ef41Sopenharmony_ci<h5><code>streamConsumers.blob(stream)</code><span><a class="mark" href="#streamconsumersblobstream" id="streamconsumersblobstream">#</a></span><a aria-hidden="true" class="legacy" id="webstreams_streamconsumers_blob_stream"></a></h5> 19971cb0ef41Sopenharmony_ci<div class="api_metadata"> 19981cb0ef41Sopenharmony_ci<span>Added in: v16.7.0</span> 19991cb0ef41Sopenharmony_ci</div> 20001cb0ef41Sopenharmony_ci<ul> 20011cb0ef41Sopenharmony_ci<li><code>stream</code> <a href="webstreams.html#class-readablestream" class="type"><ReadableStream></a> | <a href="stream.html#class-streamreadable" class="type"><stream.Readable></a> | <a href="https://tc39.github.io/ecma262/#sec-asynciterator-interface" class="type"><AsyncIterator></a></li> 20021cb0ef41Sopenharmony_ci<li>Returns: <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Promise" class="type"><Promise></a> Fulfills with a <a href="buffer.html#class-blob" class="type"><Blob></a> containing the full contents 20031cb0ef41Sopenharmony_ciof the stream.</li> 20041cb0ef41Sopenharmony_ci</ul> 20051cb0ef41Sopenharmony_ci 20061cb0ef41Sopenharmony_ci<pre class="with-50-chars"><input class="js-flavor-selector" type="checkbox" checked aria-label="Show modern ES modules syntax"><code class="language-js mjs"><span class="hljs-keyword">import</span> { blob } <span class="hljs-keyword">from</span> <span class="hljs-string">'node:stream/consumers'</span>; 20071cb0ef41Sopenharmony_ci 20081cb0ef41Sopenharmony_ci<span class="hljs-keyword">const</span> dataBlob = <span class="hljs-keyword">new</span> <span class="hljs-title class_">Blob</span>([<span class="hljs-string">'hello world from consumers!'</span>]); 20091cb0ef41Sopenharmony_ci 20101cb0ef41Sopenharmony_ci<span class="hljs-keyword">const</span> readable = dataBlob.<span class="hljs-title function_">stream</span>(); 20111cb0ef41Sopenharmony_ci<span class="hljs-keyword">const</span> data = <span class="hljs-keyword">await</span> <span class="hljs-title function_">blob</span>(readable); 20121cb0ef41Sopenharmony_ci<span class="hljs-variable language_">console</span>.<span class="hljs-title function_">log</span>(<span class="hljs-string">`from readable: <span class="hljs-subst">${data.size}</span>`</span>);</code><code class="language-js cjs"><span class="hljs-keyword">const</span> { blob } = <span class="hljs-built_in">require</span>(<span class="hljs-string">'node:stream/consumers'</span>); 20131cb0ef41Sopenharmony_ci 20141cb0ef41Sopenharmony_ci<span class="hljs-keyword">const</span> dataBlob = <span class="hljs-keyword">new</span> <span class="hljs-title class_">Blob</span>([<span class="hljs-string">'hello world from consumers!'</span>]); 20151cb0ef41Sopenharmony_ci 20161cb0ef41Sopenharmony_ci<span class="hljs-keyword">const</span> readable = dataBlob.<span class="hljs-title function_">stream</span>(); 20171cb0ef41Sopenharmony_ci<span class="hljs-title function_">blob</span>(readable).<span class="hljs-title function_">then</span>(<span class="hljs-function">(<span class="hljs-params">data</span>) =></span> { 20181cb0ef41Sopenharmony_ci <span class="hljs-variable language_">console</span>.<span class="hljs-title function_">log</span>(<span class="hljs-string">`from readable: <span class="hljs-subst">${data.size}</span>`</span>); 20191cb0ef41Sopenharmony_ci});</code><button class="copy-button">copy</button></pre> 20201cb0ef41Sopenharmony_ci<h5><code>streamConsumers.buffer(stream)</code><span><a class="mark" href="#streamconsumersbufferstream" id="streamconsumersbufferstream">#</a></span><a aria-hidden="true" class="legacy" id="webstreams_streamconsumers_buffer_stream"></a></h5> 20211cb0ef41Sopenharmony_ci<div class="api_metadata"> 20221cb0ef41Sopenharmony_ci<span>Added in: v16.7.0</span> 20231cb0ef41Sopenharmony_ci</div> 20241cb0ef41Sopenharmony_ci<ul> 20251cb0ef41Sopenharmony_ci<li><code>stream</code> <a href="webstreams.html#class-readablestream" class="type"><ReadableStream></a> | <a href="stream.html#class-streamreadable" class="type"><stream.Readable></a> | <a href="https://tc39.github.io/ecma262/#sec-asynciterator-interface" class="type"><AsyncIterator></a></li> 20261cb0ef41Sopenharmony_ci<li>Returns: <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Promise" class="type"><Promise></a> Fulfills with a <a href="buffer.html#class-buffer" class="type"><Buffer></a> containing the full 20271cb0ef41Sopenharmony_cicontents of the stream.</li> 20281cb0ef41Sopenharmony_ci</ul> 20291cb0ef41Sopenharmony_ci 20301cb0ef41Sopenharmony_ci<pre class="with-52-chars"><input class="js-flavor-selector" type="checkbox" checked aria-label="Show modern ES modules syntax"><code class="language-js mjs"><span class="hljs-keyword">import</span> { buffer } <span class="hljs-keyword">from</span> <span class="hljs-string">'node:stream/consumers'</span>; 20311cb0ef41Sopenharmony_ci<span class="hljs-keyword">import</span> { <span class="hljs-title class_">Readable</span> } <span class="hljs-keyword">from</span> <span class="hljs-string">'node:stream'</span>; 20321cb0ef41Sopenharmony_ci<span class="hljs-keyword">import</span> { <span class="hljs-title class_">Buffer</span> } <span class="hljs-keyword">from</span> <span class="hljs-string">'node:buffer'</span>; 20331cb0ef41Sopenharmony_ci 20341cb0ef41Sopenharmony_ci<span class="hljs-keyword">const</span> dataBuffer = <span class="hljs-title class_">Buffer</span>.<span class="hljs-title function_">from</span>(<span class="hljs-string">'hello world from consumers!'</span>); 20351cb0ef41Sopenharmony_ci 20361cb0ef41Sopenharmony_ci<span class="hljs-keyword">const</span> readable = <span class="hljs-title class_">Readable</span>.<span class="hljs-title function_">from</span>(dataBuffer); 20371cb0ef41Sopenharmony_ci<span class="hljs-keyword">const</span> data = <span class="hljs-keyword">await</span> <span class="hljs-title function_">buffer</span>(readable); 20381cb0ef41Sopenharmony_ci<span class="hljs-variable language_">console</span>.<span class="hljs-title function_">log</span>(<span class="hljs-string">`from readable: <span class="hljs-subst">${data.length}</span>`</span>);</code><code class="language-js cjs"><span class="hljs-keyword">const</span> { buffer } = <span class="hljs-built_in">require</span>(<span class="hljs-string">'node:stream/consumers'</span>); 20391cb0ef41Sopenharmony_ci<span class="hljs-keyword">const</span> { <span class="hljs-title class_">Readable</span> } = <span class="hljs-built_in">require</span>(<span class="hljs-string">'node:stream'</span>); 20401cb0ef41Sopenharmony_ci<span class="hljs-keyword">const</span> { <span class="hljs-title class_">Buffer</span> } = <span class="hljs-built_in">require</span>(<span class="hljs-string">'node:buffer'</span>); 20411cb0ef41Sopenharmony_ci 20421cb0ef41Sopenharmony_ci<span class="hljs-keyword">const</span> dataBuffer = <span class="hljs-title class_">Buffer</span>.<span class="hljs-title function_">from</span>(<span class="hljs-string">'hello world from consumers!'</span>); 20431cb0ef41Sopenharmony_ci 20441cb0ef41Sopenharmony_ci<span class="hljs-keyword">const</span> readable = <span class="hljs-title class_">Readable</span>.<span class="hljs-title function_">from</span>(dataBuffer); 20451cb0ef41Sopenharmony_ci<span class="hljs-title function_">buffer</span>(readable).<span class="hljs-title function_">then</span>(<span class="hljs-function">(<span class="hljs-params">data</span>) =></span> { 20461cb0ef41Sopenharmony_ci <span class="hljs-variable language_">console</span>.<span class="hljs-title function_">log</span>(<span class="hljs-string">`from readable: <span class="hljs-subst">${data.length}</span>`</span>); 20471cb0ef41Sopenharmony_ci});</code><button class="copy-button">copy</button></pre> 20481cb0ef41Sopenharmony_ci<h5><code>streamConsumers.json(stream)</code><span><a class="mark" href="#streamconsumersjsonstream" id="streamconsumersjsonstream">#</a></span><a aria-hidden="true" class="legacy" id="webstreams_streamconsumers_json_stream"></a></h5> 20491cb0ef41Sopenharmony_ci<div class="api_metadata"> 20501cb0ef41Sopenharmony_ci<span>Added in: v16.7.0</span> 20511cb0ef41Sopenharmony_ci</div> 20521cb0ef41Sopenharmony_ci<ul> 20531cb0ef41Sopenharmony_ci<li><code>stream</code> <a href="webstreams.html#class-readablestream" class="type"><ReadableStream></a> | <a href="stream.html#class-streamreadable" class="type"><stream.Readable></a> | <a href="https://tc39.github.io/ecma262/#sec-asynciterator-interface" class="type"><AsyncIterator></a></li> 20541cb0ef41Sopenharmony_ci<li>Returns: <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Promise" class="type"><Promise></a> Fulfills with the contents of the stream parsed as a 20551cb0ef41Sopenharmony_ciUTF-8 encoded string that is then passed through <code>JSON.parse()</code>.</li> 20561cb0ef41Sopenharmony_ci</ul> 20571cb0ef41Sopenharmony_ci 20581cb0ef41Sopenharmony_ci<pre class="with-50-chars"><input class="js-flavor-selector" type="checkbox" checked aria-label="Show modern ES modules syntax"><code class="language-js mjs"><span class="hljs-keyword">import</span> { json } <span class="hljs-keyword">from</span> <span class="hljs-string">'node:stream/consumers'</span>; 20591cb0ef41Sopenharmony_ci<span class="hljs-keyword">import</span> { <span class="hljs-title class_">Readable</span> } <span class="hljs-keyword">from</span> <span class="hljs-string">'node:stream'</span>; 20601cb0ef41Sopenharmony_ci 20611cb0ef41Sopenharmony_ci<span class="hljs-keyword">const</span> items = <span class="hljs-title class_">Array</span>.<span class="hljs-title function_">from</span>( 20621cb0ef41Sopenharmony_ci { 20631cb0ef41Sopenharmony_ci <span class="hljs-attr">length</span>: <span class="hljs-number">100</span>, 20641cb0ef41Sopenharmony_ci }, 20651cb0ef41Sopenharmony_ci <span class="hljs-function">() =></span> ({ 20661cb0ef41Sopenharmony_ci <span class="hljs-attr">message</span>: <span class="hljs-string">'hello world from consumers!'</span>, 20671cb0ef41Sopenharmony_ci }), 20681cb0ef41Sopenharmony_ci); 20691cb0ef41Sopenharmony_ci 20701cb0ef41Sopenharmony_ci<span class="hljs-keyword">const</span> readable = <span class="hljs-title class_">Readable</span>.<span class="hljs-title function_">from</span>(<span class="hljs-title class_">JSON</span>.<span class="hljs-title function_">stringify</span>(items)); 20711cb0ef41Sopenharmony_ci<span class="hljs-keyword">const</span> data = <span class="hljs-keyword">await</span> <span class="hljs-title function_">json</span>(readable); 20721cb0ef41Sopenharmony_ci<span class="hljs-variable language_">console</span>.<span class="hljs-title function_">log</span>(<span class="hljs-string">`from readable: <span class="hljs-subst">${data.length}</span>`</span>);</code><code class="language-js cjs"><span class="hljs-keyword">const</span> { json } = <span class="hljs-built_in">require</span>(<span class="hljs-string">'node:stream/consumers'</span>); 20731cb0ef41Sopenharmony_ci<span class="hljs-keyword">const</span> { <span class="hljs-title class_">Readable</span> } = <span class="hljs-built_in">require</span>(<span class="hljs-string">'node:stream'</span>); 20741cb0ef41Sopenharmony_ci 20751cb0ef41Sopenharmony_ci<span class="hljs-keyword">const</span> items = <span class="hljs-title class_">Array</span>.<span class="hljs-title function_">from</span>( 20761cb0ef41Sopenharmony_ci { 20771cb0ef41Sopenharmony_ci <span class="hljs-attr">length</span>: <span class="hljs-number">100</span>, 20781cb0ef41Sopenharmony_ci }, 20791cb0ef41Sopenharmony_ci <span class="hljs-function">() =></span> ({ 20801cb0ef41Sopenharmony_ci <span class="hljs-attr">message</span>: <span class="hljs-string">'hello world from consumers!'</span>, 20811cb0ef41Sopenharmony_ci }), 20821cb0ef41Sopenharmony_ci); 20831cb0ef41Sopenharmony_ci 20841cb0ef41Sopenharmony_ci<span class="hljs-keyword">const</span> readable = <span class="hljs-title class_">Readable</span>.<span class="hljs-title function_">from</span>(<span class="hljs-title class_">JSON</span>.<span class="hljs-title function_">stringify</span>(items)); 20851cb0ef41Sopenharmony_ci<span class="hljs-title function_">json</span>(readable).<span class="hljs-title function_">then</span>(<span class="hljs-function">(<span class="hljs-params">data</span>) =></span> { 20861cb0ef41Sopenharmony_ci <span class="hljs-variable language_">console</span>.<span class="hljs-title function_">log</span>(<span class="hljs-string">`from readable: <span class="hljs-subst">${data.length}</span>`</span>); 20871cb0ef41Sopenharmony_ci});</code><button class="copy-button">copy</button></pre> 20881cb0ef41Sopenharmony_ci<h5><code>streamConsumers.text(stream)</code><span><a class="mark" href="#streamconsumerstextstream" id="streamconsumerstextstream">#</a></span><a aria-hidden="true" class="legacy" id="webstreams_streamconsumers_text_stream"></a></h5> 20891cb0ef41Sopenharmony_ci<div class="api_metadata"> 20901cb0ef41Sopenharmony_ci<span>Added in: v16.7.0</span> 20911cb0ef41Sopenharmony_ci</div> 20921cb0ef41Sopenharmony_ci<ul> 20931cb0ef41Sopenharmony_ci<li><code>stream</code> <a href="webstreams.html#class-readablestream" class="type"><ReadableStream></a> | <a href="stream.html#class-streamreadable" class="type"><stream.Readable></a> | <a href="https://tc39.github.io/ecma262/#sec-asynciterator-interface" class="type"><AsyncIterator></a></li> 20941cb0ef41Sopenharmony_ci<li>Returns: <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Promise" class="type"><Promise></a> Fulfills with the contents of the stream parsed as a 20951cb0ef41Sopenharmony_ciUTF-8 encoded string.</li> 20961cb0ef41Sopenharmony_ci</ul> 20971cb0ef41Sopenharmony_ci 20981cb0ef41Sopenharmony_ci<pre class="with-50-chars"><input class="js-flavor-selector" type="checkbox" checked aria-label="Show modern ES modules syntax"><code class="language-js mjs"><span class="hljs-keyword">import</span> { text } <span class="hljs-keyword">from</span> <span class="hljs-string">'node:stream/consumers'</span>; 20991cb0ef41Sopenharmony_ci<span class="hljs-keyword">import</span> { <span class="hljs-title class_">Readable</span> } <span class="hljs-keyword">from</span> <span class="hljs-string">'node:stream'</span>; 21001cb0ef41Sopenharmony_ci 21011cb0ef41Sopenharmony_ci<span class="hljs-keyword">const</span> readable = <span class="hljs-title class_">Readable</span>.<span class="hljs-title function_">from</span>(<span class="hljs-string">'Hello world from consumers!'</span>); 21021cb0ef41Sopenharmony_ci<span class="hljs-keyword">const</span> data = <span class="hljs-keyword">await</span> <span class="hljs-title function_">text</span>(readable); 21031cb0ef41Sopenharmony_ci<span class="hljs-variable language_">console</span>.<span class="hljs-title function_">log</span>(<span class="hljs-string">`from readable: <span class="hljs-subst">${data.length}</span>`</span>);</code><code class="language-js cjs"><span class="hljs-keyword">const</span> { text } = <span class="hljs-built_in">require</span>(<span class="hljs-string">'node:stream/consumers'</span>); 21041cb0ef41Sopenharmony_ci<span class="hljs-keyword">const</span> { <span class="hljs-title class_">Readable</span> } = <span class="hljs-built_in">require</span>(<span class="hljs-string">'node:stream'</span>); 21051cb0ef41Sopenharmony_ci 21061cb0ef41Sopenharmony_ci<span class="hljs-keyword">const</span> readable = <span class="hljs-title class_">Readable</span>.<span class="hljs-title function_">from</span>(<span class="hljs-string">'Hello world from consumers!'</span>); 21071cb0ef41Sopenharmony_ci<span class="hljs-title function_">text</span>(readable).<span class="hljs-title function_">then</span>(<span class="hljs-function">(<span class="hljs-params">data</span>) =></span> { 21081cb0ef41Sopenharmony_ci <span class="hljs-variable language_">console</span>.<span class="hljs-title function_">log</span>(<span class="hljs-string">`from readable: <span class="hljs-subst">${data.length}</span>`</span>); 21091cb0ef41Sopenharmony_ci});</code><button class="copy-button">copy</button></pre></section> 21101cb0ef41Sopenharmony_ci <!-- API END --> 21111cb0ef41Sopenharmony_ci </div> 21121cb0ef41Sopenharmony_ci </div> 21131cb0ef41Sopenharmony_ci </div> 21141cb0ef41Sopenharmony_ci</body> 21151cb0ef41Sopenharmony_ci</html> 2116