Skip to main content

'A pytest plugin to test Flask-SocketIO servers.'

Project description

A simple pytest plugin for Flask-Socketio servers.

pipeline status coverage report

Quick Start


You can install using pip

$ pip install python-flask-socketio


In order to use this plugin, you must supply two fixtures (in your file: app and socketio.

import pytest
from my_app import create_app
from my_app import get_socketio

def app():
   return create_app()  # return a Flask object for your app

def socketio():
   return get_socketio()  # return the SocketIO object for your app.


If your application is imported here as either app or socketio you will need to alias it to avoid the clash between the fixture function and your application object.

Now, you’ll have some handy fixtures available to easily have some test clients for your app:

def test_single_client_connects(client):
    assert client.is_connected()

def test_many_clients_connect(clients):
    for client in clients:
        assert client.is_connected()

def test_some_broadcast_message(clients):
    clients[0].emit('my_custom_blast', {'blah': 'foo'})
    r1 = clients[1].get_received()
    r2 = clients[2].get_received()
    # assert things about r1 and r2

which you can then run with your normal pytest invocation:

$ pytest

This is particularly useful if your application has a concept of multiple clients in a single room and you need to mock several clients interactions. You could customize some of the parameters the fixtures use to your preference.

For example, say you have a game server that always emits a particular message named "move" with data in the form {"x": 0, "y": 1}. You could write a custom class to assert things about that move

from pytest_flask_socketio import EventReceiver  # just wraps a list

class MyAppsEventReceiver(EventReceiver):
    def got_move(x, y, message_index=0) -> bool:
        return[message_index]['name'] == 'move' and \
  [message_index][0]['x'] == x and \
  [message_index][0]['y'] == y

Then use it in your tests:

client_idents = ['player-A', 'player-B']
event_receiver = MyAppsEventReceiver

def test_player_move(clients):
    """ Tests Player B gets Player A's move. """
    clients['player-A'].emit('make_move', {'x': 1, 'y': 8})
    assert clients['player-B'].get_received().got_move('1', '8')

Check out the docs for more information on how you can use this plugin.

More documentation to come.


  • Contributions welcome!
  • This is a simple package but I feel it could be extended to make some handy utilities (to be honest mainly just wanted an actual-maybe-somewhat-useful-package on pypi)

Project details

Download files

Download the file for your platform. If you're not sure which to choose, learn more about installing packages.

Files for pytest-flask-socketio, version 0.1.0a0
Filename, size File type Python version Upload date Hashes
Filename, size pytest_flask_socketio-0.1.0a0-py3-none-any.whl (7.9 kB) File type Wheel Python version py3 Upload date Hashes View
Filename, size pytest-flask-socketio-0.1.0a0.tar.gz (6.9 kB) File type Source Python version None Upload date Hashes View

Supported by

Pingdom Pingdom Monitoring Google Google Object Storage and Download Analytics Sentry Sentry Error logging AWS AWS Cloud computing DataDog DataDog Monitoring Fastly Fastly CDN DigiCert DigiCert EV certificate StatusPage StatusPage Status page