Zerorpc asynchronous calls

Question

Server

Suppose I have the following zerorpc server

#server side
import zerorpc

class API():

    def long_running_task(self):
        print('1 - started long_running_task')
        #for instance a long running SQL query
        zerorpc.gevent.sleep(10)
        print('2 - finished long_running_task')

    def other_task(self):
        print('1 - started other_task')
        pass
        print('2 - finished other_task')

s = zerorpc.Server(API())
s.bind("tcp://0.0.0.0:4444")
zerorpc.gevent.spawn(s.run)
while True:
    zerorpc.gevent.sleep(10)

Client

and a client app which sends several requests simultanously

import zerorpc

client = zerorpc.Client()
client.connect("tcp://127.0.0.1:4444")

client.long_running_task(async_=True)
client.other_task(async_=True)

client.close()

The problem is that while the long_running_task is being executed the other_task doesn't start running.

The desired output is:

1 - started long_running_task
1 - started other_task
2 - finished other_task
2 - finished long_running_task

instead of

1 - started long_running_task
2 - finished long_running_task
1 - started other_task
2 - finished other_task

Answer 1

There are a few mistakes here

1. async_ should be async . This ensures client method returns immediately
2. ZeroRPC works with gevent. So you need to start the server with gevent.spawn(s.run) . Also to keep your main greenlet running.

zerorpc.gevent.spawn(s.run)
while True:
     zerorpc.gevent.sleep(10)

3. above 2 is not enough. In the API() methods you need to be co-operative too. Instead of time.sleep() use gevent.sleep() .