SetFullMethodInto a function to save the grpc full method name into watermelon context.

SetGrpcRequestTypeInto a function to save the grpc request type into watermelon context stream | unary.

SetRequestInto a function to save the grpc request body into watermelon context.

SetStreamHandlerInto a function to save the grpc stream handler into watermelon context.

SetUnaryHandlerInto a function to save the grpc unary handler into watermelon context.