What's aiohttp-cache

aiohttp-cache is a plugin for aiohttp.web server that allow to use a cache system to improve the performance of your site.

How to use it

With in-memory backend

import asyncio
from aiohttp import web
from aiohttp_cache import (  # noqa
    setup_cache,
    cache,
)
PAYLOAD = {"hello": "aiohttp_cache"}
WAIT_TIME = 2
@cache()
async def some_long_running_view(
    request: web.Request,
) -> web.Response:
    await asyncio.sleep(WAIT_TIME)
    payload = await request.json()
    return web.json_response(payload)
app = web.Application()
setup_cache(app)
app.router.add_post("/", some_long_running_view)
web.run_app(app)

With redis backend

Note: redis should be available at $CACHE_URL env variable orredis://localhost:6379/0

import asyncio
import yarl
from aiohttp import web
from envparse import env
from aiohttp_cache import (  # noqa
    setup_cache,
    cache,
    RedisConfig,
)
PAYLOAD = {"hello": "aiohttp_cache"}
WAIT_TIME = 2
@cache()
async def some_long_running_view(
    request: web.Request,
) -> web.Response:
    await asyncio.sleep(WAIT_TIME)
    payload = await request.json()
    return web.json_response(payload)
app = web.Application()
url = yarl.URL(
    env.str("CACHE_URL", default="redis://localhost:6379/0")
)
setup_cache(
    app,
    cache_type="redis",
    backend_config=RedisConfig(
        db=int(url.path[1:]), host=url.host, port=url.port
    ),
)
app.router.add_post("/", some_long_running_view)
web.run_app(app)

Example with a custom cache key

Let's say you would like to cache the requests just by the method and json payload, then you can setup this as per the follwing example.

Note default key_pattern is:

DEFAULT_KEY_PATTERN = (
    AvailableKeys.method,
    AvailableKeys.host,
    AvailableKeys.path,
    AvailableKeys.postdata,
    AvailableKeys.ctype,
)

import asyncio
from aiohttp import web
from aiohttp_cache import (
    setup_cache,
    cache,
    AvailableKeys,
)  # noqa
PAYLOAD = {"hello": "aiohttp_cache"}
WAIT_TIME = 2
@cache()
async def some_long_running_view(
    request: web.Request,
) -> web.Response:
    await asyncio.sleep(WAIT_TIME)
    payload = await request.json()
    return web.json_response(payload)
custom_cache_key = (AvailableKeys.method, AvailableKeys.json)
app = web.Application()
setup_cache(app, key_pattern=custom_cache_key)
app.router.add_post("/", some_long_running_view)
web.run_app(app)

Parametrize the cache decorator

import asyncio
from aiohttp import web
from aiohttp_cache import (  # noqa
    setup_cache,
    cache,
)
PAYLOAD = {"hello": "aiohttp_cache"}
WAIT_TIME = 2
@cache(
    expires=1 * 24 * 3600,  # in seconds
    unless=False,  # anything what returns a bool. if True - skips cache
)
async def some_long_running_view(
    request: web.Request,
) -> web.Response:
    await asyncio.sleep(WAIT_TIME)
    payload = await request.json()
    return web.json_response(payload)
app = web.Application()
setup_cache(app)
app.router.add_post("/", some_long_running_view)
web.run_app(app)

License

This project is released under BSD license. Feel free

Source Code

The latest developer version is available in a github repository: https://github.com/cr0hn/aiohttp-cache

Development environment

docker-compose run tests