问题
Here is my python file
import os
from google.appengine.api import channel
from google.appengine.ext import webapp
from google.appengine.ext.webapp import template
from google.appengine.ext.webapp.util import run_wsgi_app
import logging
token = 'default'
class SendMessage(webapp.RequestHandler):
def post(self):
logging.info('Sending messgae with tokens : ' + token)
channel.send_message(token,'Hello from the server')
class MainPage(webapp.RequestHandler):
def get(self):
global token
token = channel.create_channel('ram')
logging.info('Token : ' + token)
channel.send_message(token,'Hello from the server')
template_values = {'token': token}
path = os.path.join(os.path.dirname(__file__), 'index.html')
self.response.out.write(template.render(path, template_values))
application = webapp.WSGIApplication([
('/', MainPage),('/sendmessage',SendMessage)], debug=True)
def main():
run_wsgi_app(application)
if __name__ == "__main__":
main()
and HTML file
<html>
<head>
<script type="text/javascript" src="https://talkgadget.google.com/talkgadget/channel.js"></script>
</head>
<body >
<script>
var state = {
token: '{{ token }}'
};
var token = state.token;
openChannel = function () {
var channel = new goog.appengine.Channel(token.toString());
var socket = channel.open();
socket.onopen = function () {
alert('open');
};
socket.onmessage = function () {
alert('message');
};
socket.onerror = function () {
alert('error');
};
socket.onclose = function () {
alert('close');
};
};
sendMessage = function () {
var xhr = new XMLHttpRequest();
xhr.open('POST', '/sendmessage', true);
xhr.send();
};
</script>
Hi All, <br>
<button onclick="openChannel()">Open Connection</button>
<button onclick="sendMessage()">Send Message</button>
</body>
</html>
On the page there is Open Connection button that create the channel to the created token on server side. Now when I click on this button it flashes the error alert and then close alert. I want to make a channel and send message from server to the browser.
Am I missing something ?
来源：https://stackoverflow.com/questions/34332222/unable-to-create-new-channel-in-javascript-of-channel-api