@Override
  public void resolveArtifacts(
      ArtifactApi.ResolveArtifactsRequest request,
      StreamObserver<ArtifactApi.ResolveArtifactsResponse> responseObserver) {
    responseObserver.onNext(
        ArtifactApi.ResolveArtifactsResponse.newBuilder()
            .addAllReplacements(resolver.resolveArtifacts(request.getArtifactsList()))
            .build());
    responseObserver.onCompleted();
  }
@Test
  public void testResolveArtifacts() throws IOException {
    RunnerApi.ArtifactInformation artifact = fileArtifact(Paths.get("somePath"));
    ArtifactApi.ResolveArtifactsResponse resolved =
        retrievalBlockingStub.resolveArtifacts(
            ArtifactApi.ResolveArtifactsRequest.newBuilder().addArtifacts(artifact).build());
    assertEquals(1, resolved.getReplacementsCount());
    assertEquals(artifact, resolved.getReplacements(0));
  }