CORS proxy

proxy.py

# -*- coding: utf-8 -*-

# forwards the calls to http://localhost:8000/https://google.com to https://google.com - copying the headers, query strings, etc

from fastapi import FastAPI, Request, Response
from fastapi.middleware.cors import CORSMiddleware
import requests

app = FastAPI()

origins = [
    "*",
]

app.add_middleware(
    CORSMiddleware,
    allow_origins=origins,
    allow_credentials=True,
    allow_methods=["*"],
    allow_headers=["*"],
)

method_requests_mapping = {
    "GET": requests.get,
    "HEAD": requests.head,
    "POST": requests.post,
    "PUT": requests.put,
    "DELETE": requests.delete,
    "PATCH": requests.patch,
    "OPTIONS": requests.options,
}


# @app.api_route("/{path_name:path}", methods=["GET"])
@app.api_route("/{path_name:path}", methods=method_requests_mapping.keys())
async def proxy(request: Request, path_name: str):
    requests_function = method_requests_mapping[request.method]

    body = b""
    async for chunk in request.stream():
        body += chunk

    url = f"{path_name}?{request.query_params}"
    headers = {key: value for key, value in request.headers.items() if key != "host"}
    outgoing_request = requests_function(url, stream=True, data=body, headers=headers)

    response = Response(
        outgoing_request.content, status_code=outgoing_request.status_code
    )
    response.headers["Access-Control-Allow-Origin"] = "*"
    return response

requirements.txt

fastapi
uvicorn[standard]
requests

serve

uvicorn proxy:app --reload

setup

# set -euo pipefail
python3 -m venv venv
. venv/bin/activate
python -m pip install -r equirements.txt
pushd venv/bin
python_interpreter_path=`pwd`
echo $python_interpreter_path/python
popd