flask.sessions SessionMixin Example Code

SessionMixin is a class used with Flask projects that is defined in the flask.sessions module. SessionMixin expands a standard Python dictionary with session attributes.

BadSignature and SessionInterface are a couple of other callables within the flask.sessions package that also have code examples.

Example 1 from Flask-SocketIO

Flask-SocketIO (PyPI package information, official tutorial and project documentation) is a code library by Miguel Grinberg that provides Socket.IO integration for Flask applications. This extension makes it easier to add bi-directional communications on the web via the WebSockets protocol.

The Flask-SocketIO project is open source under the MIT license.

Flask-SocketIO / flask_socketio / init.py

# __init__.py
from functools import wraps
import os
import sys

gevent_socketio_found = True
    from socketio import socketio_manage  # noqa: F401
except ImportError:
    gevent_socketio_found = False
if gevent_socketio_found:
    print('The gevent-socketio package is incompatible with this version of '
          'the Flask-SocketIO extension. Please uninstall it, and then '
          'install the latest version of python-socketio in its place.')

import flask
from flask import _request_ctx_stack, has_request_context, json as flask_json
from flask.sessions import SessionMixin
import socketio
from socketio.exceptions import ConnectionRefusedError  # noqa: F401
from werkzeug.debug import DebuggedApplication
from werkzeug.serving import run_with_reloader

from .namespace import Namespace
from .test_client import SocketIOTestClient

__version__ = '5.0.2dev'

class _SocketIOMiddleware(socketio.WSGIApp):
    def __init__(self, socketio_app, flask_app, socketio_path='socket.io'):
        self.flask_app = flask_app
        super(_SocketIOMiddleware, self).__init__(socketio_app,

    def __call__(self, environ, start_response):
        environ = environ.copy()
        environ['flask.app'] = self.flask_app
        return super(_SocketIOMiddleware, self).__call__(environ,

class _ManagedSession(dict, SessionMixin):

class SocketIO(object):

    def __init__(self, app=None, **kwargs):
        self.server = None
        self.server_options = {}
        self.wsgi_server = None
        self.handlers = []
        self.namespace_handlers = []
        self.exception_handlers = {}
        self.default_exception_handler = None
        self.manage_session = True
        if app is not None or 'message_queue' in kwargs:
            self.init_app(app, **kwargs)

    def init_app(self, app, **kwargs):
        if app is not None:
            if not hasattr(app, 'extensions'):
                app.extensions = {}  # pragma: no cover
            app.extensions['socketio'] = self

## ... source file continues with no further SessionMixin examples...

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