nocdnbs/app.py

from flask import Flask, redirect, render_template, request

app = Flask(__name__)

@app.route('/')
def home():
    domain = request.url_root
    return render_template('index.html', domain=domain)

@app.route('/<path:url>')
def proxy(url):
    jsdelivr_url = f'https://cdnjs.cloudflare.com/{url}'
    return redirect(jsdelivr_url)

if __name__ == '__main__':
    app.run()