Can I write a single decorator combining @tornado.gen.coroutine and @run_on_executor.

[VARSHAJOSHY]

I have written a code, and it was working well if my function doesnt have any yield statements, but not working when I was yielding the response as given below,

def tornadoWrapper(func):
      @run_on_executor
      def custom_executor(self, *args, **kwargs):
           return func(self, *args, **kwargs)

      @tornado.gen.coroutine
      def cutsom_gencoroutine(*args, **kwargs):
            yield custom_executor(*args, **kwargs)

class DummyHandlerWihourYield:
     @tornadoWrapper()
     def get(self):
          result = self.getResult()

class DummyHandlerWithYield:
     @tornadoWrapper()
     def get(self):
          result = yield self.getResult()
         
     def getResult(sef):
          #doing some processing

Also I would like to know (becoz I am bit confused on the concepts). Lets say I have hosted a webservice,

1. if it doesnt have any 'yield', that means I have to support only multithreading not asynchronous - That means I need only @run_on_executor
2. If it is yielding any result , which means I have to support both multithreading and asynchronous. I need both @run_on_executor and @tornado.gen.coroutine

Please correct me If I am wrong here.

[bdarnell]

I don't think it's possible to do what you want here. Tornado is designed to be single-threaded, and if you try to automatically use threads you'll find that you can't do the kinds of things that a handler needs to do (for example, you're only allowed to call self.finish() from the event loop thread). When you're learning to use Tornado, I recommend not using threads at all, and only introducing threads after you have a solid grasp of asynchronous concurrency within a single thread.

[VARSHAJOSHY]

I found the solution - simply remove the yield used in get()

def tornadoWrapper(func):
      @run_on_executor
      def custom_executor(self, *args, **kwargs):
           return func(self, *args, **kwargs)

      @tornado.gen.coroutine
      def cutsom_gencoroutine(*args, **kwargs):
            yield custom_executor(*args, **kwargs)
            
            
class DummyHandlerWithYield:
     @tornadoWrapper()
     def get(self):
          result = self.getResult()
         
     def getResult(sef):
          #doing some processing