AttributeError: 'WebSocketHandler' object has no attribute 'write_messsage' - python-2.7

Question

I am attempting to build a server that takes user requests for long(ish)-running jobs, updates the user as the job progresses, and returns some data for the client to use. I am attempting to use tornado's WebSocketHandler to do this. Is there a reason I can't call a WebSocketHandler's write_message method from another object?
import tornado.ioloop
import tornado.websocket
import json, sys, os
from uuid import uuid4
class MainHandler(tornado.web.RequestHandler):
def get(self):
self.write('Welcome to the site. Requests cannot be made to the main page.')
class WSInvalidRequest(Exception):
"""Called when user sends invalid request to the server."""
pass
class WSRequestQueue:
def __init__(self):
self._items = []
def put(self, item):
self._items.append(item)
return self._items.length()
def get(self):
return self._items.pop(0)
def get_position(self, item):
return self._items.index(item)
QUEUE = WSRequestQueue()
class WSRequest:
def __init__(self, message, websocket):
self.websocket = websocket
self.ran = False
self.valid = False
self.write(u'Request received.')
try:
self.request = WSRequest.parse_message(message)
self.valid = True
self.write(u'Request validated.')
position = QUEUE.put(self)
self.write(u'Added request to queue behind %i other requests.' % position)
except WSInvalidRequest as e: self.write(e.message)
#staticmethod
def validate_request_dict(request):
if not isinstance(messageDict, dict):
raise WSInvalidRequest(u'Invalid request. Should be JSON dict string.')
if 'arg' not in request:
raise WSInvalidRequest(u'Invalid request. No arg found')
#staticmethod
def parse_message(message):
messageDict = json.loads(message)
validate_request_dict(messageDict)
argument = messsageDict['arg']
return {'argumet': argument}
def write(self, message):
self.websocket.write_messsage(unicode(message))
def run(self):
self.ran = True
def destroy(self):
if self.valid:
if not self.ran: QUEUE.pop(QUEUE.get_position(self))
self.websocket.requests.remove(self)
self.write(u'Removed request from queue.')
class RequestWebSocket(tornado.websocket.WebSocketHandler):
def open(self):
self.id = uuid4()
self.requests = set()
print("WebSocket opened")
def on_message(self, message):
self.write_message(u'You sent: %s' % message)
self.write_message(u'Attempting to add your request to the queue.')
newRequest = WSRequest(message, self)
if newRequest.valid: self.requests.add(newRequest)
else: newRequest.destroy
def on_close(self):
print("WebSocket closed. Removing all requests from the queue.")
for request in self.requests: request.destroy()
def check_origin(self, origin):
return True
if __name__ == "__main__":
# Create the web server
application = tornado.web.Application([
(r'/', MainHandler),
(r'/websocket', RequestWebSocket)
], debug=True)
application.listen(80)
tornado.ioloop.IOLoop.instance().start()

Answer 1

There's a spelling mistake in write_messsage. There's an extra s.
It's at:
class WSRequest:
def write(self, message):
self.websocket.write_messsage(unicode(message))
# ^ extra 's'