app.py

from starlette.applications import Starlette
from starlette.exceptions import HTTPException
from starlette.responses import FileResponse, JSONResponse, HTMLResponse
from starlette.requests import Request
from starlette.routing import Route


async def homepage(_):
    return FileResponse("static/index.html")


async def healthz(_):
    return JSONResponse({"success": True})


async def convert(req: Request):
    url = req.query_params.get("url")
    if not url:
        raise HTTPException(400, "Param url is missing")
    print(url)
    return HTMLResponse("<strong>FOO</strong>")


app = Starlette(
    debug=True,
    routes=[
        Route("/", homepage),
        Route("/healthz", healthz),
        Route("/convert", convert),
    ],
)