from fastapi import FastAPI
from fastapi.responses import PlainTextResponse
from pytheus.exposition import generate_metrics
from pytheus.middleware import PytheusMiddlewareASGI

from pytheus.backends import load_backend
from pytheus.backends.redis import MultiProcessRedisBackend

load_backend(
    backend_class=MultiProcessRedisBackend,
    backend_config={"host": "127.0.0.1", "port": 6379},
)

app = FastAPI()
app.add_middleware(PytheusMiddlewareASGI)


@app.get("/metrics", response_class=PlainTextResponse)
async def pytheus_metrics():
    return generate_metrics()