Fastapi hướng dẫn sử dụng get cache và set cache

from typing import Union

from fastapi import HTTPException, Request

import json
from fastapi import APIRouter, Depends
import redis.asyncio as redis
import httpx

from lib.redis import redis_client

post_route = APIRouter()

async def get_redis():
    return redis_client

@post_route.get("/")
async def postroot():
    return { "status" : 1 , "message" : "Đây là post index"}

@post_route.post("/{key}")
async def set_cache(key: str, request: Request, r = Depends(get_redis)):
    # Ưu tiên dữ liệu JSON
    value = None
    content_type = request.headers.get("content-type", "")

    if "application/json" in content_type:
        try:
            body = await request.json()
            value = body.get("value")
        except Exception:
            raise HTTPException(status_code=400, detail="Invalid JSON")
    elif "application/x-www-form-urlencoded" in content_type or "multipart/form-data" in content_type:
        form = await request.form()
        value = form.get("value")
    else:
        raise HTTPException(status_code=415, detail="Unsupported Content-Type")

    if value is None:
        raise HTTPException(status_code=422, detail="Missing 'value'")

    await r.set(key, value)
    return {"message": "Key stored", "key": key, "value": value}



@post_route.get("/{key}")
async def get_cache(key: str, r = Depends(get_redis)):
    value = await r.get(key)
    if value is None:
        async with httpx.AsyncClient() as client:
            res = await client.get('https://dummyjson.com/products/1')
            if res.status_code != 200:
                raise HTTPException(status_code=500, detail="Failed to fetch data")
            data = res.json()
            await r.set(key, json.dumps(data), ex=3600)  # TTL: 1 giờ
            return {"key": key, "value": data}
    return {"key": key, "value": json.loads(value)}