How to use

deserializeServerFailure

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 server failure serialization.
 */
@Test
public void testServerFailureSerialization() throws Exception {
  IllegalStateException cause = new IllegalStateException("Expected test");
  ByteBuf buf = MessageSerializer.serializeServerFailure(alloc, cause);
  int frameLength = buf.readInt();
  assertEquals(MessageType.SERVER_FAILURE, MessageSerializer.deserializeHeader(buf));
  Throwable request = MessageSerializer.deserializeServerFailure(buf);
  assertEquals(buf.readerIndex(), frameLength + 4);
  assertEquals(cause.getClass(), request.getClass());
  assertEquals(cause.getMessage(), request.getMessage());
}

/**
 * Tests that the channel is closed if an Exception reaches the channel handler.
 */
@Test
public void testCloseChannelOnExceptionCaught() 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(handler);
  channel.pipeline().fireExceptionCaught(new RuntimeException("Expected test Exception"));
  ByteBuf buf = (ByteBuf) readInboundBlocking(channel);
  buf.skipBytes(4); // skip frame length
  // Verify the response
  assertEquals(MessageType.SERVER_FAILURE, MessageSerializer.deserializeHeader(buf));
  Throwable response = MessageSerializer.deserializeServerFailure(buf);
  assertTrue(response.getMessage().contains("Expected test Exception"));
  channel.closeFuture().await(READ_TIMEOUT_MILLIS);
  assertFalse(channel.isActive());
}

Throwable response = MessageSerializer.deserializeServerFailure(buf);
response = MessageSerializer.deserializeServerFailure(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);
  }
}