How to stop flask application without using ctrl-c

I want to implement a command which can stop flask application by using flask-script. I have searched the solution for a while. Because the framework doesn't provide app.stop() API, I am curious about how to code this. I am working on Ubuntu 12.10 and Python 2.7.3.

Solution 1:

If you are just running the server on your desktop, you can expose an endpoint to kill the server (read more at Shutdown The Simple Server):

from flask import request
def shutdown_server():
    func = request.environ.get('werkzeug.server.shutdown')
    if func is None:
        raise RuntimeError('Not running with the Werkzeug Server')
    func()
    
@app.get('/shutdown')
def shutdown():
    shutdown_server()
    return 'Server shutting down...'
    

Here is another approach that is more contained:

from multiprocessing import Process

server = Process(target=app.run)
server.start()
# ...
server.terminate()
server.join()

Let me know if this helps.

Solution 2:

I did it slightly different using threads

from werkzeug.serving import make_server

class ServerThread(threading.Thread):

    def __init__(self, app):
        threading.Thread.__init__(self)
        self.server = make_server('127.0.0.1', 5000, app)
        self.ctx = app.app_context()
        self.ctx.push()

    def run(self):
        log.info('starting server')
        self.server.serve_forever()

    def shutdown(self):
        self.server.shutdown()

def start_server():
    global server
    app = flask.Flask('myapp')
    ...
    server = ServerThread(app)
    server.start()
    log.info('server started')

def stop_server():
    global server
    server.shutdown()

I use it to do end to end tests for restful api, where I can send requests using the python requests library.

Solution 3:

This is a bit old thread, but if someone experimenting, learning, or testing basic flask app, started from a script that runs in the background, the quickest way to stop it is to kill the process running on the port you are running your app on. Note: I am aware the author is looking for a way not to kill or stop the app. But this may help someone who is learning.

sudo netstat -tulnp | grep :5001

You'll get something like this.

tcp 0 0 0.0.0.0:5001 0.0.0.0:* LISTEN 28834/python

To stop the app, kill the process

sudo kill 28834