kaya/packages/kaya-session-redis/README.md

kaya-session-redis

Redis-backed session storage for the Kaya web framework.

Provides RedisSessionStore, a SessionStore implementation (from kaya-session) that persists session data in Redis, so sessions are shared across processes and hosts.

Usage

from redis.asyncio import Redis

from kaya.core import KayaApp, HttpContext
from kaya.session import SessionMixin
from kaya.session.redis import RedisSessionStore

client = Redis(host='localhost', port=6379)
session = SessionMixin(RedisSessionStore(client))
app = KayaApp(mixins=[session])

@app.GET('/')
async def home(ctx: HttpContext):
    n = ctx.session.get('visits', 0) + 1
    ctx.session['visits'] = n
    await ctx.send_str(200, f'visits: {n}')

Sessions are stored under keys with the prefix kaya:session: (configurable via the prefix argument). Server-side expiry uses Redis key TTLs and slides on each access when the session mixin passes a max_age.

Serialization

Session data is serialized with pickle by default, so arbitrary Python objects can be stored. A different serializer can be plugged in via the dumps/loads arguments:

import json

store = RedisSessionStore(
    client,
    dumps=lambda d: json.dumps(d).encode('utf-8'),
    loads=lambda b: json.loads(b.decode('utf-8')),
)

Warning: pickle deserialization of untrusted data is unsafe. Only use the default serializer with a trusted Redis server.