mariatta / aiohttp-session

Provides sessions for aiohttp.web

aiohttp_session

The library provides sessions for aiohttp.web.

Usage

The library allows us to store user-specific data into a session object.

The session object has a dict-like interface (operations like session[key] = value, value = session[key] etc. are present).

Before processing the session in a web-handler, you have to register the session middleware in aiohttp.web.Application.

A trivial usage example:

import time
import base64
from cryptography import fernet
from aiohttp import web
from aiohttp_session import setup, get_session
from aiohttp_session.cookie_storage import EncryptedCookieStorage


async def handler(request):
    session = await get_session(request)
    last_visit = session['last_visit'] if 'last_visit' in session else None
    session['last_visit'] = time.time()
    text = 'Last visited: {}'.format(last_visit)
    return web.Response(text=text)


def make_app():
    app = web.Application()
    # secret_key must be 32 url-safe base64-encoded bytes
    fernet_key = fernet.Fernet.generate_key()
    secret_key = base64.urlsafe_b64decode(fernet_key)
    setup(app, EncryptedCookieStorage(secret_key))
    app.router.add_get('/', handler)
    return app


web.run_app(make_app())

All storages use an HTTP Cookie named AIOHTTP_SESSION for storing data. This can be modified by passing the keyword argument cookie_name to the storage class of your choice.

Available session storages are:

• aiohttp_session.SimpleCookieStorage() -- keeps session data as a plain JSON string in the cookie body. Use the storage only for testing purposes, it's very non-secure.

• aiohttp_session.cookie_storage.EncryptedCookieStorage(secret_key) -- stores the session data into a cookie as SimpleCookieStorage but encodes it via AES cipher. secrect_key is a bytes key for AES encryption/decryption, the length should be 32 bytes.

  Requires cryptography library:

  $ pip install aiohttp_session[secure]

• aiohttp_session.redis_storage.RedisStorage(redis_pool) -- stores JSON encoded data in redis, keeping only the redis key (a random UUID) in the cookie. redis_pool is a aioredis pool object, created by await aioredis.create_redis_pool(...) call.

  Requires aioredis library (only versions 1.0+ are supported):

  $ pip install aiohttp_session[aioredis]

Developing

Install for local development:

$ pip install -r requirements-dev.txt

Run tests with:

$ pytest -sv tests/

Third party extensions

• aiohttp_session_mongo
• aiohttp_session_dynamodb

License

aiohttp_session is offered under the Apache 2 license.