[websocket] WebSocket proxy should return status code depending on type of PulsarClientException

[massakam]

Motivation

If the WebSocket proxy fails to create a producer or consumer, it should return the suitable HTTP status code to the client depending on the type of PulsarClientException that occurred. However, there are currently only a few exceptions where the WebSocket proxy returns a status code other than 500.

pulsar/pulsar-websocket/src/main/java/org/apache/pulsar/websocket/ProducerHandler.java

Lines 119 to 129 in 7be1b8d

	private static int getErrorCode(Exception e) {
	if (e instanceof IllegalArgumentException) {
	return HttpServletResponse.SC_BAD_REQUEST;
	} else if (e instanceof ProducerBusyException) {
	return HttpServletResponse.SC_CONFLICT;
	} else if (e instanceof ProducerBlockedQuotaExceededError || e instanceof ProducerBlockedQuotaExceededException) {
	return HttpServletResponse.SC_SERVICE_UNAVAILABLE;
	} else {
	return HttpServletResponse.SC_INTERNAL_SERVER_ERROR;
	}
	}

Modifications

Moved the getErrorCode() method from ProducerHandler and ConsumerHandler to AbstractWebSocketHandler and increased the types of PulsarClientException to handle.

[codelipenghui]

The change looks good to me. Could you please also some tests for the new change?

[massakam]

@codelipenghui It's hard to cover all cases, so added tests for some of them.