使用autbahn.asyncio.wamp非阻塞地运行多个ApplicationSessions

Question

我试图在python中同时运行两个autobahn.asyncio.wamp.ApplicationSessions。以前，我使用this post's answer中建议的修改高速公路库来做到这一点。我现在需要更专业的解决方案。

谷歌搜索了一段时间，this post appeared quite promising，但使用twisted库，而不是asyncio。我无法为asyncio图书馆的autobahn分支找到类似的解决方案，因为它似乎没有使用Reactors。

我遇到的主要问题是ApplicationRunner.run()是阻塞的（这就是我之前把它外包给一个线程的原因），所以我不能在它之后运行第二个ApplicationRunner。

我确实需要同时访问2个websocket频道，我似乎无法用一个ApplicationSession。

我的代码到目前为止：

from autobahn.asyncio.wamp import ApplicationSession
from autobahn.asyncio.wamp import ApplicationRunner
from asyncio import coroutine
import time


channel1 = 'BTC_LTC'
channel2 = 'BTC_XMR'

class LTCComponent(ApplicationSession):

    def onConnect(self):
        self.join(self.config.realm)

    @coroutine
    def onJoin(self, details):
        def onTicker(*args, **kwargs):
            print('LTCComponent', args, kwargs)

        try:
            yield from self.subscribe(onTicker, channel1)
        except Exception as e:
            print("Could not subscribe to topic:", e)

class XMRComponent(ApplicationSession):

    def onConnect(self):
        self.join(self.config.realm)

    @coroutine
    def onJoin(self, details):
        def onTicker(*args, **kwargs):
            print('XMRComponent', args, kwargs)

        try:
            yield from self.subscribe(onTicker, channel2)
        except Exception as e:
            print("Could not subscribe to topic:", e)

def main():
    runner = ApplicationRunner("wss://api.poloniex.com:443", "realm1", extra={})
    runner.run(LTCComponent)
    runner.run(XMRComponent) # <- is not being called


if __name__ == "__main__":

    try:
        main()
    except KeyboardInterrupt:
        quit()

    except Exception as e:
        print(time.time(), e)

我对autobahn库的了解有限，我担心文档并没有改善我的情况。我在这里俯瞰什么吗？一个函数，一个参数，它可以让我复合我的组件或同时运行它们？

也许与provided here类似的解决方案，它实现了另一种ApplicationRunner？

---

相关话题

Running two ApplicationSessions in twisted

Running Autobahn ApplicationRunner in Thread

Autobahn.wamp.ApplicationSession Source

Autobahn.wamp.Applicationrunner Source

---

正如请求的那样，来自@ stovfl使用multithreading代码回答的Traceback：

Exception in thread Thread-2:
Traceback (most recent call last):
  File "/home/nils/anaconda3/lib/python3.5/threading.py", line     914, in _bootstrap_inner
    self.run()
  File "/home/nils/git/tools/gemini_wss/t2.py", line 27, in run
    self.appRunner.run(self.__ApplicationSession)
  File "/home/nils/anaconda3/lib/python3.5/site-packages/autobahn-    0.14.1-py3.5.egg/autobahn/asyncio/wamp.py", line 143,     in run
    transport_factory = WampWebSocketClientFactory(create,         url=self.url,                 serializers=self.serializers)
  File "/home/nils/anaconda3/lib/python3.5/site-packages/autobahn-    0.14.1-py3.5.egg/autobahn/asyncio/websocket.py", line     319, in __init__
    WebSocketClientFactory.__init__(self, *args, **kwargs)
  File "/home/nils/anaconda3/lib/python3.5/site-packages/autobahn-    0.14.1-py3.5.egg/autobahn/asyncio/websocket.py", line     268, in __init__
    self.loop = loop or asyncio.get_event_loop()
  File "/home/nils/anaconda3/lib/python3.5/asyncio/events.py",     line 626, in get_event_loop
    return get_event_loop_policy().get_event_loop()
  File "/home/nils/anaconda3/lib/python3.5/asyncio/events.py",     line 572, in get_event_loop
    % threading.current_thread().name)
RuntimeError: There is no current event loop in thread 'Thread-2'.
Exception in thread Thread-1:
**Same as in Thread-2**
...
RuntimeError: There is no current event loop in thread 'Thread-1'.

Answer 1

遵循you linked for twisted的方法我设法使用asyncio设置start_loop = False获得相同的行为

import asyncio
from autobahn.asyncio.wamp import ApplicationSession, ApplicationRunner

runner1 = ApplicationRunner(url, realm, extra={'cli_id': 1})
coro1 = runner1.run(MyApplicationSession, start_loop=False)

runner2 = ApplicationRunner(url, realm, extra={'cli_id': 2})
coro2 = runner2.run(MyApplicationSession, start_loop=False)

asyncio.get_event_loop().run_until_complete(coro1)
asyncio.get_event_loop().run_until_complete(coro2)
asyncio.get_event_loop().run_forever()

class MyApplicationSession(ApplicationSession):

    def __init__(self, cfg):
        super().__init__(cfg)
        self.cli_id = cfg.extra['cli_id']

   def onJoin(self, details):
        print("session attached", self.cli_id)

Answer 2

正如我从traceback看到的那样，我们只能达到第4步

来自asyncio文档： 该模块提供了使用协程编写单线程并发代码的基础结构，通过套接字和其他资源多路复用I / O访问

所以我使用multithreading删除了我的第一个提案。 我可以想象以下三个选项：

1. 用multiprocessing代替multithreading
2. 在coroutine里面用asyncio loop做
3. 切换在channels的def onJoin(self, details)

---

第二个提案，使用multiprocessing的第一个选项。 我可以开始两个asyncio loops，所以appRunner.run(...)应该工作。

如果class ApplicationSession是唯一的不同，你可以使用一个channel。如果你需要通过不同的class ApplicationSession添加到args=

class __ApplicationSession(ApplicationSession):
        # ...
        try:
            yield from self.subscribe(onTicker, self.config.extra['channel'])
        except Exception as e:
            # ...

import multiprocessing as mp
import time

def ApplicationRunner_process(realm, channel):
        appRunner = ApplicationRunner("wss://api.poloniex.com:443", realm, extra={'channel': channel})
        appRunner.run(__ApplicationSession)

if __name__ == "__main__":
    AppRun = [{'process':None, 'channel':'BTC_LTC'},
              {'process': None, 'channel': 'BTC_XMR'}]

    for app in AppRun:
        app['process'] =  mp.Process(target = ApplicationRunner_process, args = ('realm1', app['channel'] ))
        app['process'].start()
        time.sleep(0.1)

    AppRun[0]['process'].join()
    AppRun[1]['process'].join()