Flask throwing 'working outside of request context' when starting sub thread

Question

I am trying to start a new thread in Python inside of a Flask application. I am doing background work that gets triggered by the request, but I don\'t need to wait for the

Answer 1

Wrap your thread code in a test_request_context so you have access to context locals:

@app.route('/my_endpoint', methods=['POST'])
def my_endpoint_handler():
    #do tracking in sub-thread so we don't hold up the page
    def handle_sub_view(req):
        with app.test_request_context():
            from flask import request
            request = req
            # Do Expensive work
    thread.start_new_thread(handle_sub_view, (request))
    return "Thanks"

Edit: it's worth pointing out that the thread will have a different context than the original request. You need to extract any interesting request data, such as the user ID, before spawning the thread. You can then grab a (different) user object in the sub-thread using the ID.