# How to programmatically stop dash app gracefully?

**URL:** <https://community.plotly.com/t/how-to-programmatically-stop-dash-app-gracefully/72939>\
**Category:** Dash Python\
**Created:** [February 22, 2023, 9:10am UTC](https://community.plotly.com/t/how-to-programmatically-stop-dash-app-gracefully/72939 "2023-02-22T09:10:00Z")\
**Posts on this page:** 6\
**Page:** 1

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**Author:** ![mmm2310](https://avatars.discourse-cdn.com/v4/letter/m/cab0a1/32.png) [@mmm2310](https://community.plotly.com/u/mmm2310)\
**Post date:** [February 22, 2023, 9:10am UTC](https://community.plotly.com/t/how-to-programmatically-stop-dash-app-gracefully/72939/1 "2023-02-22T09:10:00Z")

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Have a dash app develped using python on VSCode + Jupyter.  
Wish to stop the app, after task is done. I have tried…  
a) def stop\_execution():  
subprocess.run([“jupyter”, “notebook”, “stop”, “all”])  
b) pid = os.getpid()  
os.kill(pid, signal.SIGINT)  
Option b) does the job, but abrupt closing message and kernel dies…  
Manually clicking stop execution button on VS Code works,but  
Am sure there has to be some way (or may be JS) to stop execution programmatically.

(Am laughing at myself, thinking of a joke wherein a person rides bike without knowing how to stop…Someone please help me quick before I crash!!) Cheers.

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**Author:** ![jinnyzor](https://sea2.discourse-cdn.com/flex024/user_avatar/community.plotly.com/jinnyzor/32/21194_2.png) [@jinnyzor](https://community.plotly.com/u/jinnyzor)\
**Post date:** [February 22, 2023, 12:44pm UTC](https://community.plotly.com/t/how-to-programmatically-stop-dash-app-gracefully/72939/2 "2023-02-22T12:44:23Z")

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Hello @mmm2310,

Welcome to the community!

You could try to use a supervisor instead. And then the supervisor is easy to control from the command line, or inside an app, etc.

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**Author:** ![mmm2310](https://avatars.discourse-cdn.com/v4/letter/m/cab0a1/32.png) [@mmm2310](https://community.plotly.com/u/mmm2310)\
**Post date:** [February 22, 2023, 2:53pm UTC](https://community.plotly.com/t/how-to-programmatically-stop-dash-app-gracefully/72939/3 "2023-02-22T14:53:11Z")

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Thanks for your reply. Sorry, but I have not used Supervisor earlier. Please help me with any similar use case in Python. Thanks again.

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<div class="post-metadata">

**Author:** ![mmm2310](https://avatars.discourse-cdn.com/v4/letter/m/cab0a1/32.png) [@mmm2310](https://community.plotly.com/u/mmm2310)\
**Post date:** [February 23, 2023, 4:45am UTC](https://community.plotly.com/t/how-to-programmatically-stop-dash-app-gracefully/72939/4 "2023-02-23T04:45:51Z")

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One update. Am using Windows. Just searched documentation for supervisor and learnt it is meant for UNIX and MacOS…but, " Supervisor will _not_ run at all under any version of Windows". I guess, Supervisor is what os.kill or SIGINT are meant to do…but it causes abrupt end.  
Any other method to gracefully exit dash app programmatically ??

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<div class="post-metadata">

**Author:** ![mmm2310](https://avatars.discourse-cdn.com/v4/letter/m/cab0a1/32.png) [@mmm2310](https://community.plotly.com/u/mmm2310)\
**Post date:** [February 23, 2023, 7:39am UTC](https://community.plotly.com/t/how-to-programmatically-stop-dash-app-gracefully/72939/5 "2023-02-23T07:39:38Z")

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Good day,  
I found a solution to gracefully exit dash app. For the benefit of others, am posting code snippet here…

```auto
def stop_execution():
    global keepPlot
    #stream.stop_stream()
    keepPlot=False
    # stop the Flask server
    server.shutdown()
    server_thread.join()
    print("Dash app stopped gracefully.")
    
    
server = Flask( __name__ )
app = Dash( __name__ , server=server)

if __name__ == " __main__":
    # create a server instance
    server = make_server("localhost", 8050, server)
    # start the server in a separate thread
    server_thread = threading.Thread(target=server.serve_forever)
    server_thread.start()

    # start the Dash app in a separate thread
    def start_dash_app():
        app.run_server(debug=True, use_reloader=False)

    dash_thread = threading.Thread(target=start_dash_app)
    dash_thread.start()

    while keepPlot:
        time.sleep(1) # keep the main thread alive while the other threads are running

```

Trick is to run app in two separate threads…and run stop\_execution() when u wish to stop execution.

Thanks and have a nice day.

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<div class="post-metadata">

**Author:** ![jinnyzor](https://sea2.discourse-cdn.com/flex024/user_avatar/community.plotly.com/jinnyzor/32/21194_2.png) [@jinnyzor](https://community.plotly.com/u/jinnyzor)\
**Post date:** [February 23, 2023, 8:09am UTC](https://community.plotly.com/t/how-to-programmatically-stop-dash-app-gracefully/72939/6 "2023-02-23T08:09:31Z")

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Hello @mmm2310,

Glad you got something that works, and thank you for posting what works in your case.

Dash is stateless, so, typically needing to save graphs, etc is unnecessary because everything is normally with the client’s interface.

This is what allows multiple servers to run.

Is there a benefit to it stopping gracefully vs quitting the service running it?