content: /*
   * Licensed to the Apache Software Foundation (ASF) under one
   * or more contributor license agreements.  See the NOTICE file
   * distributed with this work for additional information
   * regarding copyright ownership.  The ASF licenses this file
   * to you under the Apache License, Version 2.0 (the
   * "License"); you may not use this file except in compliance
   * with the License.  You may obtain a copy of the License at
   *
   *     http://www.apache.org/licenses/LICENSE-2.0
   *
   * Unless required by applicable law or agreed to in writing, software
   * distributed under the License is distributed on an "AS IS" BASIS,
   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
   * See the License for the specific language governing permissions and
   * limitations under the License.
   */
  package org.apache.beam.runners.fnexecution.state;
  
  import static org.hamcrest.CoreMatchers.equalTo;
  import static org.hamcrest.MatcherAssert.assertThat;
  import static org.mockito.ArgumentMatchers.any;
  import static org.mockito.Mockito.never;
  import static org.mockito.Mockito.times;
  import static org.mockito.Mockito.verify;
  
  import java.nio.charset.StandardCharsets;
  import java.util.concurrent.BlockingDeque;
  import java.util.concurrent.CompletableFuture;
  import java.util.concurrent.LinkedBlockingDeque;
  import java.util.concurrent.TimeUnit;
  import org.apache.beam.model.fnexecution.v1.BeamFnApi;
  import org.apache.beam.sdk.fn.test.TestStreams;
  import org.apache.beam.vendor.grpc.v1p69p0.com.google.protobuf.ByteString;
  import org.apache.beam.vendor.grpc.v1p69p0.io.grpc.stub.StreamObserver;
  import org.junit.Before;
  import org.junit.Rule;
  import org.junit.Test;
  import org.junit.rules.Timeout;
  import org.junit.runner.RunWith;
  import org.junit.runners.JUnit4;
  import org.mockito.Mock;
  import org.mockito.Mockito;
  import org.mockito.MockitoAnnotations;
  
  /** Tests for {@link org.apache.beam.runners.fnexecution.state.GrpcStateService}. */
  @RunWith(JUnit4.class)
  @SuppressWarnings({
    "rawtypes", // TODO(https://github.com/apache/beam/issues/20447)
  })
  public class GrpcStateServiceTest {
    @Rule public transient Timeout globalTimeout = Timeout.seconds(600);
    private static final long TIMEOUT_MS = 30 * 1000;
  
    private GrpcStateService stateService;
  
    @Mock private StreamObserver<BeamFnApi.StateResponse> responseObserver;
  
    @Mock private StateRequestHandler handler;
  
    @Before
    public void setUp() throws Exception {
      MockitoAnnotations.initMocks(this);
      stateService = GrpcStateService.create();
    }
  
    /**
     * After a handler has been registered with {@link
     * GrpcStateService#registerForProcessBundleInstructionId(String, StateRequestHandler)}, the
     * {@link GrpcStateService} should delegate requests through {@link
     * GrpcStateService#state(StreamObserver)} to the registered handler.
     */
    @Test
    public void testStateRequestsHandledByRegisteredHandlers() throws Exception {
      // register handler
      String bundleInstructionId = "bundle_instruction";
      stateService.registerForProcessBundleInstructionId(bundleInstructionId, handler);
  
      // open state stream
      StreamObserver requestObserver = stateService.state(responseObserver);
  
      // send state request
      BeamFnApi.StateRequest request =
          BeamFnApi.StateRequest.newBuilder().setInstructionId(bundleInstructionId).build();
      requestObserver.onNext(request);
  
      // assert behavior
      verify(handler).handle(request);
    }
  
    @Test
    public void testHandlerResponseSentToStateStream() throws Exception {
      // define handler behavior
      ByteString expectedResponseData =
          ByteString.copyFrom("EXPECTED_RESPONSE_DATA", StandardCharsets.UTF_8);
      String bundleInstructionId = "EXPECTED_BUNDLE_INSTRUCTION_ID";
      BeamFnApi.StateResponse.Builder expectedBuilder =
          BeamFnApi.StateResponse.newBuilder()
              .setGet(BeamFnApi.StateGetResponse.newBuilder().setData(expectedResponseData));
      StateRequestHandler dummyHandler =
          request -> {
            CompletableFuture<BeamFnApi.StateResponse.Builder> response = new CompletableFuture<>();
            response.complete(expectedBuilder);
            return response;
          };
  
      // define observer behavior
      BlockingDeque<BeamFnApi.StateResponse> responses = new LinkedBlockingDeque<>();
      StreamObserver<BeamFnApi.StateResponse> recordingResponseObserver =
          TestStreams.withOnNext(responses::add).build();
      recordingResponseObserver = Mockito.spy(recordingResponseObserver);
  
      // register handler
      stateService.registerForProcessBundleInstructionId(bundleInstructionId, dummyHandler);
  
      // open state stream
      StreamObserver<BeamFnApi.StateRequest> requestObserver =
          stateService.state(recordingResponseObserver);
  
      // send state request
      BeamFnApi.StateRequest request =
          BeamFnApi.StateRequest.newBuilder().setInstructionId(bundleInstructionId).build();
      requestObserver.onNext(request);
  
      // wait for response
      BeamFnApi.StateResponse response = responses.poll(TIMEOUT_MS, TimeUnit.MILLISECONDS);
  
      // assert that responses contain a built state response
      verify(recordingResponseObserver, times(1)).onNext(any());
      verify(recordingResponseObserver, never()).onCompleted();
      verify(recordingResponseObserver, never()).onError(any());
      assertThat(response.getGet().getData(), equalTo(expectedResponseData));
    }
  }
  