python - Sending messages actively from Tornado WebSocket server -

i have python websocket server. can return response when receives message.

import tornado.web import tornado.websocket import tornado.ioloop  class websockethandler(tornado.websocket.websockethandler):      def open(self):         print("new client connected")         self.write_message("you connected")      def on_message(self, message):         self.write_message(u"you said: " + message)      def on_close(self):         print("client disconnected")      def check_origin(self, origin):         return true  application = tornado.web.application([         (r"/", websockethandler), ])   if __name__ == "__main__":     application.listen(8888)     tornado.ioloop.ioloop.instance().start() 

however, can't send messages before receives one. how send message actively? example, measures time , if didn't receive messages 10 sec, send "are sleeping?".

i want make chatbot using websocket. use tornado , websocket because know this, , interested if know of better methods use in regard.

you can add schedule tornado.ioloop.periodiccallback , check if there has been activity or not based on time, following (i adapted code , this answer):

import tornado.web import tornado.websocket import tornado.ioloop import time  class websockethandler(tornado.websocket.websockethandler):     def simple_init(self):         self.last = time.time()         self.stop = false      def open(self):         self.simple_init()         print("new client connected")         self.write_message("you connected")         self.loop = tornado.ioloop.periodiccallback(self.check_ten_seconds, 1000, io_loop=tornado.ioloop.ioloop.instance())         self.loop.start()      def on_message(self, message):         self.write_message(u"you said: " + message)         self.last = time.time()      def on_close(self):         print("client disconnected")         self.loop.stop()      def check_origin(self, origin):         return true      def check_ten_seconds(self):         print("just checking")         if (time.time() - self.last > 10):             self.write_message("you sleeping mate?")             self.last = time.time() 

now client alternating between idling , writing (adapted here):

class client(object):     def __init__(self, url, timeout):         self.url = url         self.timeout = timeout         self.ioloop = ioloop.instance()         self.ws = none         self.connect()         periodiccallback(self.keep_alive, 20000, io_loop=self.ioloop).start()         self.ioloop.start()      @gen.coroutine     def connect(self):         print("trying connect")         try:             self.ws = yield websocket_connect(self.url)         except exception e:             print("connection error")         else:             print("connected")             self.run()      @gen.coroutine     def run(self):         once = false         while true:             msg = yield self.ws.read_message()             print(msg)             if once:                 time.sleep(11)                 once = false             else:                 time.sleep(1)                 once = true             self.ws.write_message("hello matey")             if msg none:                 print("connection closed")                 self.ws = none                 break      def keep_alive(self):         if self.ws none:             self.connect()         else:             self.ws.write_message("keep alive") 

we obtain expected output:

trying connect connected connected said: hello matey sleeping mate? said: hello matey said: hello matey sleeping mate?