gistfile1.txt

@app.route('/<path:path>', methods=['OPTIONS'])
def allow_cors(path):
    resp = current_app.make_default_options_response()
    resp.headers['Access-Control-Allow-Origin'] = request.headers.get('Origin')
    resp.headers['Access-Control-Allow-Methods'] = 'GET, POST, PUT'
    resp.headers['Access-Control-Max-Age'] = '21600'
    resp.headers['Access-Control-Allow-Credentials'] = 'true'
    return resp