How to use

deserializeRequestFailure

method

in

org.apache.flink.queryablestate.network.messages.MessageSerializer

@Override
public void channelRead(ChannelHandlerContext ctx, Object msg) throws Exception {
  try {
    ByteBuf buf = (ByteBuf) msg;
    MessageType msgType = MessageSerializer.deserializeHeader(buf);
    if (msgType == MessageType.REQUEST_RESULT) {
      long requestId = MessageSerializer.getRequestId(buf);
      RESP result = serializer.deserializeResponse(buf);
      callback.onRequestResult(requestId, result);
    } else if (msgType == MessageType.REQUEST_FAILURE) {
      RequestFailure failure = MessageSerializer.deserializeRequestFailure(buf);
      callback.onRequestFailure(failure.getRequestId(), failure.getCause());
    } else if (msgType == MessageType.SERVER_FAILURE) {
      throw MessageSerializer.deserializeServerFailure(buf);
    } else {
      throw new IllegalStateException("Unexpected response type '" + msgType + "'");
    }
  } catch (Throwable t1) {
    try {
      callback.onFailure(t1);
    } catch (Throwable t2) {
      LOG.error("Failed to notify callback about failure", t2);
    }
  } finally {
    ReferenceCountUtil.release(msg);
  }
}

/**
 * Tests request failure serialization.
 */
@Test
public void testKvStateRequestFailureSerialization() throws Exception {
  long requestId = Integer.MAX_VALUE + 1111222L;
  IllegalStateException cause = new IllegalStateException("Expected test");
  ByteBuf buf = MessageSerializer.serializeRequestFailure(alloc, requestId, cause);
  int frameLength = buf.readInt();
  assertEquals(MessageType.REQUEST_FAILURE, MessageSerializer.deserializeHeader(buf));
  RequestFailure requestFailure = MessageSerializer.deserializeRequestFailure(buf);
  assertEquals(buf.readerIndex(), frameLength + 4);
  assertEquals(requestId, requestFailure.getRequestId());
  assertEquals(cause.getClass(), requestFailure.getCause().getClass());
  assertEquals(cause.getMessage(), requestFailure.getCause().getMessage());
}

RequestFailure response = MessageSerializer.deserializeRequestFailure(buf);

RequestFailure response = MessageSerializer.deserializeRequestFailure(buf);

RequestFailure response = MessageSerializer.deserializeRequestFailure(buf);
assertEquals(182828L, response.getRequestId());
assertTrue(response.getCause().getMessage().contains("IOException"));
response = MessageSerializer.deserializeRequestFailure(buf);
assertEquals(182829L, response.getRequestId());
assertTrue(response.getCause().getMessage().contains("IOException"));

/**
 * Tests the failure response with {@link UnknownKvStateIdException} as cause on
 * queries for unregistered KvStateIDs.
 */
@Test
public void testQueryUnknownKvStateID() throws Exception {
  KvStateRegistry registry = new KvStateRegistry();
  AtomicKvStateRequestStats stats = new AtomicKvStateRequestStats();
  MessageSerializer<KvStateInternalRequest, KvStateResponse> serializer =
      new MessageSerializer<>(new KvStateInternalRequest.KvStateInternalRequestDeserializer(), new KvStateResponse.KvStateResponseDeserializer());
  KvStateServerHandler handler = new KvStateServerHandler(testServer, registry, serializer, stats);
  EmbeddedChannel channel = new EmbeddedChannel(getFrameDecoder(), handler);
  long requestId = Integer.MAX_VALUE + 182828L;
  KvStateInternalRequest request = new KvStateInternalRequest(new KvStateID(), new byte[0]);
  ByteBuf serRequest = MessageSerializer.serializeRequest(channel.alloc(), requestId, request);
  // Write the request and wait for the response
  channel.writeInbound(serRequest);
  ByteBuf buf = (ByteBuf) readInboundBlocking(channel);
  buf.skipBytes(4); // skip frame length
  // Verify the response
  assertEquals(MessageType.REQUEST_FAILURE, MessageSerializer.deserializeHeader(buf));
  RequestFailure response = MessageSerializer.deserializeRequestFailure(buf);
  assertEquals(requestId, response.getRequestId());
  assertTrue("Did not respond with expected failure cause", response.getCause() instanceof UnknownKvStateIdException);
  assertEquals(1L, stats.getNumRequests());
  assertEquals(1L, stats.getNumFailed());
}

RequestFailure response = MessageSerializer.deserializeRequestFailure(buf);

@Override
public void channelRead(ChannelHandlerContext ctx, Object msg) throws Exception {
  try {
    ByteBuf buf = (ByteBuf) msg;
    MessageType msgType = MessageSerializer.deserializeHeader(buf);
    if (msgType == MessageType.REQUEST_RESULT) {
      long requestId = MessageSerializer.getRequestId(buf);
      RESP result = serializer.deserializeResponse(buf);
      callback.onRequestResult(requestId, result);
    } else if (msgType == MessageType.REQUEST_FAILURE) {
      RequestFailure failure = MessageSerializer.deserializeRequestFailure(buf);
      callback.onRequestFailure(failure.getRequestId(), failure.getCause());
    } else if (msgType == MessageType.SERVER_FAILURE) {
      throw MessageSerializer.deserializeServerFailure(buf);
    } else {
      throw new IllegalStateException("Unexpected response type '" + msgType + "'");
    }
  } catch (Throwable t1) {
    try {
      callback.onFailure(t1);
    } catch (Throwable t2) {
      LOG.error("Failed to notify callback about failure", t2);
    }
  } finally {
    ReferenceCountUtil.release(msg);
  }
}

@Override
public void channelRead(ChannelHandlerContext ctx, Object msg) throws Exception {
  try {
    ByteBuf buf = (ByteBuf) msg;
    MessageType msgType = MessageSerializer.deserializeHeader(buf);
    if (msgType == MessageType.REQUEST_RESULT) {
      long requestId = MessageSerializer.getRequestId(buf);
      RESP result = serializer.deserializeResponse(buf);
      callback.onRequestResult(requestId, result);
    } else if (msgType == MessageType.REQUEST_FAILURE) {
      RequestFailure failure = MessageSerializer.deserializeRequestFailure(buf);
      callback.onRequestFailure(failure.getRequestId(), failure.getCause());
    } else if (msgType == MessageType.SERVER_FAILURE) {
      throw MessageSerializer.deserializeServerFailure(buf);
    } else {
      throw new IllegalStateException("Unexpected response type '" + msgType + "'");
    }
  } catch (Throwable t1) {
    try {
      callback.onFailure(t1);
    } catch (Throwable t2) {
      LOG.error("Failed to notify callback about failure", t2);
    }
  } finally {
    ReferenceCountUtil.release(msg);
  }
}