Django Channels Consumer Not Connecting to websocket
i created a websocket with javascripts on the client side...then followed up with setting up my project to handle webocket connections as follows(following the official django-channels documentation). But each time i refresh the page and watch the websocket from the browser console...its fails. i inserted an print statement in the init of the consumer class and it was printed(each time a page containing a websocket was visited or refreshed)..which mean that the routing is working fine...but for some reasons the consumer is not connecting/accepting the connection as expected to the websocket. and again there is no log in the development server as to any websocket connection process.Please can anyone help and suggest a fix.
my setting.py file(relevant lines)
INSTALLED_APPS = [
...
'channels',
]
ASGI_APPLICATION = 'ma_mall.asgi.application'
CHANNEL_LAYERS = {
"default": {
'BACKEND': "channels_redis.core.RedisChannelLayer",
"CONFIG": {
'hosts': [('127.0.0.1', 6379)],
}
}
}
my asgi.py file
application = ProtocolTypeRouter({
"http": get_asgi_application(),
"websocket": URLRouter(
routing.websocket_urlpatterns
)
})
my routing.py file
websocket_urlpatterns = [
path("ws/notifications/", consumers.NotificationConsumer),
]
my consumer file
class NotificationConsumer(AsyncJsonWebsocketConsumer):
groups = ['general_group']
async def connect(self):
await self.accept()
await self.channel_layer.group_add('notification_group', self.channel_name)
await self.channel_layer.group_send('notification_group',
{
'type': 'tester.message',
'tester': 'tester'
}
)
async def disconnect(self, close_code):
await self.channel_layer.group_discard('notification_group', self.channel_name)
the javascript for the websocket on the client-side
i created as websocket on the client side using javascript as follows
const notification_websocket = new WebSocket(
'ws://' +
window.location.host +
'/ws/notifications/'
);
notification_websocket.onmessage = function (e) {
let data = JSON.parse(e.data);
console.log("Just received this from the back end.. 0", data);
}
notification_websocket.onclose = function (e) {
console.log("websocket closed");
}
I have not understood very well channels but I remember I had the same troubles time ago and I solved by adding the function called like the type parameter like in the examples.
class NotificationConsumer(AsyncJsonWebsocketConsumer):
groups = ['general_group']
async def connect(self):
await self.accept()
await self.channel_layer.group_add('notification_group', self.channel_name)
await self.channel_layer.group_send('notification_group',
{
'type': 'tester.message',
'tester': 'tester'
}
)
async def disconnect(self, close_code):
await self.channel_layer.group_discard('notification_group', self.channel_name)
def tester_message(self, event):
self.send(text_data=event["tester"])
i realized that i had used an Older Version of Redis (to go around using redis on Windows) and the issue happen to be coming from the redis part of the configuration. Once i switched from using Redis to using a Memcache
CHANNEL_LAYERS = {
"default": {
"BACKEND": "channels.layers.InMemoryChannelLayer"
}
}
the websocket-consumer connection connected and was kept open as expected... i hope to find a solution to using Redis newer version on Windows for development