Method downloadGraphProfile

3rdparty/libprocess/src/memory_profiler.cpp:878–931

Future<http::Response> MemoryProfiler::downloadGraphProfile(
    const http::Request& request,
    const Option<http::authentication::Principal>&)
{
  Result<time_t> requestedId = extractIdFromRequest(request);

  // Verify that `id` has the correct version if it was explicitly passed.
  if (requestedId.isError()) {
    return http::BadRequest(
        "Invalid parameter 'id': " + requestedId.error() + ".\n");
  }

  if (currentRun.isSome() && !requestedId.isSome()) {
    return http::BadRequest(
        "A profiling run is currently in progress. To download results of the"
        " previous run, please pass an 'id' explicitly.\n");
  }

  if (rawProfile.isError()) {
    return http::BadRequest(
        "No source profile exists: " + rawProfile.error() + ".\n");
  }

  const string rawProfilePath = rawProfile->getPath();
  const time_t rawProfileId = rawProfile->getId();

  // Only requests for the latest available version are allowed.
  if (requestedId.isSome() && (requestedId.get() != rawProfileId)) {
    return http::BadRequest(
        "Cannot serve requested id #" + stringify(requestedId.get()) + ".\n");
  }

  // Generate the profile for the latest available version
  // or return the cached file on disk.
  if (graphProfile.isError() || (graphProfile->getId() != rawProfileId)) {
    graphProfile = DiskArtifact::create(
        GRAPH_FILENAME,
        rawProfileId,
        [rawProfilePath](const string& outputPath) -> Try<Nothing> {
          return generateJeprofFile(
              rawProfilePath,
              "--svg",
              outputPath);
        });
  }

  if (graphProfile.isSome()) {
    return graphProfile->asHttp();
  } else {
    const string message = "Cannot generate file: " + graphProfile.error();
    LOG(WARNING) << message;
    return http::BadRequest(message + ".\n");
  }
}


// TODO(bevers): Allow passing custom options via query parameters.