API on dockerized application not reachable from host
You're problem is most likely caused by flask using the "wrong" IP:Running on http://127.0.0.1:5000/
Default for flask is to listen on localhost only, in this case that would be localhost within the container and not localhost of the docker host.
Try starting flask like this instead:flask.run(host='0.0.0.0', port=5000)