SocketIO-Flask-Debug

Holy cow, I have finally made the Werkzeug debugger work with gevent-socketio, see below for usage.

# Server-side usage

from socketio.server import SocketIOServer
from socketio.namespace import BaseNamespace
from debugger import SocketIODebugger

class MyNamespace(BaseNamespace):
  def on_my_message(self, data):
    do_something()

app.debug=True
app = SocketIODebugger(app, evalex=True, namespace=MyNamespace)

SocketIOServer((host, port), app, resource='socket.io', policy_server=False).serve_forever()

// Client-side usage

socket.on("exception", function () {
  window.location.reload(true);
});

To test it, run python app.py, then browse to http://127.0.0.1:8080 and click on the buttons.

How it works:

• extract the values from the generator returned by werkzeug.debug.DebuggedApplication whenever a socket.io request is spotted, this enables to establish the socket connection properly;
• if a namespace is specified, wrap the namespace handlers in debugger's try/catch blocks;
• if an exception is caught within the namespace, save the full original traceback and emit an "exception" socket message;
• inject exception reraising into app.before_request() which allows forwarding any incoming requests to the debugger if an exception was caught within the namespace.

Python dependencies: flask, werkzeug, gevent, gevent-socketio.