Add kaya-session-memcache package for memcached-backed session storage

2026-07-23 22:11:06 +08:00
parent e469839af3
commit 2d86a3a187
9 changed files with 405 additions and 1 deletions
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+# kaya-session-memcache
+
+Memcached-backed session storage for the Kaya web framework.
+
+Provides `MemcacheSessionStore`, a `SessionStore` implementation (from
+`kaya-session`) that persists session data in memcached via `aiomcache`, so
+sessions are shared across processes and hosts.
+
+## Usage
+
+```python
+import aiomcache
+
+from kaya.core import KayaApp, HttpContext
+from kaya.session import SessionMixin
+from kaya.session_memcache import MemcacheSessionStore
+
+client = aiomcache.Client('127.0.0.1', 11211)
+session = SessionMixin(MemcacheSessionStore(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 memcached item expiration
+and slides on each access when the session mixin passes a `max_age`. TTLs
+larger than 30 days are automatically converted to absolute Unix timestamps,
+as required by the memcached protocol.
+
+## 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:
+
+```python
+import json
+
+store = MemcacheSessionStore(
+    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 memcached server.