FastAPI使用异步Redis

1. 安装依赖

pip install fastapi redis uvicorn

2. 主要代码

#!/usr/bin/env python
import os
import sys
from contextlib import AbstractAsyncContextManager, asynccontextmanager
from datetime import timedelta
from pathlib import Path

from fastapi import FastAPI, Request
from pydantic import BaseModel
from redis import asyncio as aioredis


class RegisterRedis(AbstractAsyncContextManager):
    def __init__(self, app: FastAPI, *args, **kw) -> None:
        app.state.redis = self._redis = aioredis.Redis(*args, **kw)

    async def __aenter__(self) -> "RegisterRedis":
        await self._redis.ping()
        return self

    async def __aexit__(self, *args, **kw):
        await self._redis.aclose()

    @staticmethod
    def get_client(request: Request) -> aioredis.Redis:
        return request.app.state.redis


@asynccontextmanager
async def lifespan(app: FastAPI):
    async with RegisterRedis(app):
        yield


app = FastAPI(lifespan=lifespan)


@app.get("/")
async def get_all_redis_keys(request: Request) -> list[str]:
    redis = RegisterRedis.get_client(request)
    return await redis.keys()


class Item(BaseModel):
    key: str
    value: str | int | float | bytes
    expire: int | timedelta | None = None


@app.post("/")
async def set_key_value(request: Request, item: Item) -> dict[str, str]:
    redis = RegisterRedis.get_client(request)
    await redis.set(item.key, item.value, item.expire or None)
    value = await redis.get(item.key)
    return {item.key: value.decode()}


def runserver() -> None:
    """This is for debug mode to start server. For prod, use supervisor+gunicorn instead."""
    import uvicorn  # type:ignore

    root_app = Path(__file__).stem + ":app"
    auto_reload = "PYCHARM_HOSTED" not in os.environ
    host = "0.0.0.0"
    port = 8000
    if sys.argv[1:]:
        port = int(sys.argv[1])
    if sys.platform == "darwin" or sys.platform.lower().startswith("win"):
        tool = "open" if Path("/usr/bin/open").exists() else "explorer"
        os.system(f"{tool} http://127.0.0.1:{port}")  # Auto open browser
    uvicorn.run(root_app, host=host, port=port, reload=auto_reload)


if __name__ == "__main__":
    runserver()