tornado concurrent

tornado_concurrency.py

#!/bin/env python
import tornado.gen
import tornado.httpserver
import tornado.ioloop
import tornado.options
import tornado.web
# 这个并发库在python3自带;在python2需要安装sudo pip install futures
from tornado.options import define, options

define("port", default=8002, help="run on the given port", type=int)


import time

from tornado.concurrent import run_on_executor
from concurrent.futures import ThreadPoolExecutor   # `pip install futures` for python2

MAX_WORKERS = 4


class Handler(tornado.web.RequestHandler):
    executor = ThreadPoolExecutor(max_workers=MAX_WORKERS)

    @run_on_executor
    def background_task(self, i):
        """ This will be executed in `executor` pool. """
        time.sleep(float(i))
        return i

    @tornado.gen.coroutine
    def get(self, idx):
        """ Request that asynchronously calls background task. """
        res = yield self.background_task(idx)
        self.write(res)


if __name__ == "__main__":
    tornado.options.parse_command_line()
    app = tornado.web.Application(handlers=[
            (r"/sleep/(.+)", Handler), ])
    http_server = tornado.httpserver.HTTPServer(app)
    http_server.listen(options.port)
    tornado.ioloop.IOLoop.instance().start()