1#include "demo/include/blobstore.h"
2#include "demo/src/main.rs.h"
3#include <algorithm>
4#include <functional>
5#include <set>
6#include <string>
7#include <unordered_map>
8
9namespace org {
10namespace blobstore {
11
12// Toy implementation of an in-memory blobstore.
13//
14// In reality the implementation of BlobstoreClient could be a large complex C++
15// library.
16class BlobstoreClient::impl {
17  friend BlobstoreClient;
18  using Blob = struct {
19    std::string data;
20    std::set<std::string> tags;
21  };
22  std::unordered_map<uint64_t, Blob> blobs;
23};
24
25BlobstoreClient::BlobstoreClient() : impl(new class BlobstoreClient::impl) {}
26
27// Upload a new blob and return a blobid that serves as a handle to the blob.
28uint64_t BlobstoreClient::put(MultiBuf &buf) const {
29  std::string contents;
30
31  // Traverse the caller's chunk iterator.
32  //
33  // In reality there might be sophisticated batching of chunks and/or parallel
34  // upload implemented by the blobstore's C++ client.
35  while (true) {
36    auto chunk = next_chunk(buf);
37    if (chunk.size() == 0) {
38      break;
39    }
40    contents.append(reinterpret_cast<const char *>(chunk.data()), chunk.size());
41  }
42
43  // Insert into map and provide caller the handle.
44  auto blobid = std::hash<std::string>{}(contents);
45  impl->blobs[blobid] = {std::move(contents), {}};
46  return blobid;
47}
48
49// Add tag to an existing blob.
50void BlobstoreClient::tag(uint64_t blobid, rust::Str tag) const {
51  impl->blobs[blobid].tags.emplace(tag);
52}
53
54// Retrieve metadata about a blob.
55BlobMetadata BlobstoreClient::metadata(uint64_t blobid) const {
56  BlobMetadata metadata{};
57  auto blob = impl->blobs.find(blobid);
58  if (blob != impl->blobs.end()) {
59    metadata.size = blob->second.data.size();
60    std::for_each(blob->second.tags.cbegin(), blob->second.tags.cend(),
61                  [&](auto &t) { metadata.tags.emplace_back(t); });
62  }
63  return metadata;
64}
65
66std::unique_ptr<BlobstoreClient> new_blobstore_client() {
67  return std::make_unique<BlobstoreClient>();
68}
69
70} // namespace blobstore
71} // namespace org
72