Class MetadataUtilsTest

stub/src/test/java/io/grpc/stub/MetadataUtilsTest.java:48–175

import org.junit.runners.JUnit4;

@RunWith(JUnit4.class)
public class MetadataUtilsTest {

  @Rule public final GrpcCleanupRule grpcCleanup = new GrpcCleanupRule();

  private static final String SERVER_NAME = "test";
  private static final Metadata.Key<String> FOO_KEY =
      Metadata.Key.of("foo-key", Metadata.ASCII_STRING_MARSHALLER);

  private final MethodDescriptor<String, String> echoMethod =
      MethodDescriptor.newBuilder(StringMarshaller.INSTANCE, StringMarshaller.INSTANCE)
          .setFullMethodName("test/echo")
          .setType(MethodDescriptor.MethodType.UNARY)
          .build();

  private final ServerCallHandler<String, String> echoCallHandler =
      ServerCalls.asyncUnaryCall(
          (req, respObserver) -> {
            respObserver.onNext(req);
            respObserver.onCompleted();
          });

  MethodDescriptor<String, String> echoServerStreamingMethod =
      MethodDescriptor.newBuilder(StringMarshaller.INSTANCE, StringMarshaller.INSTANCE)
          .setFullMethodName("test/echoStream")
          .setType(MethodDescriptor.MethodType.SERVER_STREAMING)
          .build();

  private final AtomicReference<Metadata> trailersCapture = new AtomicReference<>();
  private final AtomicReference<Metadata> headersCapture = new AtomicReference<>();

  @Test
  public void shouldAttachHeadersToResponse() throws IOException {
    Metadata extras = new Metadata();
    extras.put(FOO_KEY, "foo-value");

    ServerServiceDefinition serviceDef =
        ServerInterceptors.intercept(
            ServerServiceDefinition.builder("test").addMethod(echoMethod, echoCallHandler).build(),
            ImmutableList.of(newAttachMetadataServerInterceptor(extras)));

    grpcCleanup.register(newInProcessServerBuilder().addService(serviceDef).build().start());
    ManagedChannel channel =
        grpcCleanup.register(
            newInProcessChannelBuilder()
                .intercept(newCaptureMetadataInterceptor(headersCapture, trailersCapture))
                .build());

    String response =
        ClientCalls.blockingUnaryCall(channel, echoMethod, CallOptions.DEFAULT, "hello");
    assertThat(response).isEqualTo("hello");
    assertThat(trailersCapture.get() == null || !trailersCapture.get().containsKey(FOO_KEY))
        .isTrue();
    assertThat(headersCapture.get().get(FOO_KEY)).isEqualTo("foo-value");
  }

  @Test
  public void shouldAttachTrailersWhenNoResponse() throws IOException {