How to define a global error handler in gRPC python

Question

Im trying to catch any exception that is raised in any servicer so I can make sure that I only propagate known exceptions and not unexpected ones like ValueError, TypeError etc.

Answer 1

Maybe this will help you :)

def _wrap_rpc_behavior(handler, fn):
    if handler is None:
        return None

    if handler.request_streaming and handler.response_streaming:
        behavior_fn = handler.stream_stream
        handler_factory = grpc.stream_stream_rpc_method_handler
    elif handler.request_streaming and not handler.response_streaming:
        behavior_fn = handler.stream_unary
        handler_factory = grpc.stream_unary_rpc_method_handler
    elif not handler.request_streaming and handler.response_streaming:
        behavior_fn = handler.unary_stream
        handler_factory = grpc.unary_stream_rpc_method_handler
    else:
        behavior_fn = handler.unary_unary
        handler_factory = grpc.unary_unary_rpc_method_handler

    return handler_factory(fn(behavior_fn,
                              handler.request_streaming,
                              handler.response_streaming),
                           request_deserializer=handler.request_deserializer,
                           response_serializer=handler.response_serializer)


class TracebackLoggerInterceptor(grpc.ServerInterceptor):

    def intercept_service(self, continuation, handler_call_details):
        def latency_wrapper(behavior, request_streaming, response_streaming):

            def new_behavior(request_or_iterator, servicer_context):
                try:
                    return behavior(request_or_iterator, servicer_context)
                except Exception as err:
                    logger.exception(err, exc_info=True)
            return new_behavior

        return _wrap_rpc_behavior(continuation(handler_call_details),    latency_wrapper)