Flask-socketio, emit an event to another namespace

Question

I am using Flask-socketio (http://flask-socketio.readthedocs.org/en/latest/). I am currently getting a ``` KeyError: '/local' ``` when using this in events.py. Note the differing namespaces: ``` @socketio.on('connect', namespace='/photo') def client_connect(): emit('event', { 'type': 'client_connect' }, namespace='/local') ``` Using Flask-socketio is it possible to emit to a separate namespace to that which the event occurred on? The documentation seems to suggest so, but I can't workout why I keep getting the KeyError. EDIT: Thanks @Miguel for your proposed answer, I have tried again (after a long time away from the project) but still get a keyerror with the below: ``` @socketio.on('connect', namespace='/local') def local_client_connect(): print ('Local client connected.') @socketio.on('connect', namespace='/photo') def client_connect(): print ('Client connected.') send('client_connect', namespace='/local') ``` When I run the app I see the printed 'Local client connected.' and only t…

Accepted Answer

You need to have at least one handler on the second namespace. For example:

```
@socketio.on('connect', namespace='/local')
def local_client_connect():
    pass
```

Then Flask-SocketIO will know about `/local` and will be able to emit messages to it.

Flask-socketio, emit an event to another namespace

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