.kill() do not work when { shell: true }

[LeonardoRick]

Describe the bug
.kill() do not kill python process spawned when { shell: true } is defined. I checked this awesome thread on stackoverflow, but I don't think this can be done here, since I'm not finding the PID of the spawned process. (PythonShell do not have a pid property)

Python code

import time
import sys

class Unbuffered(object):
    def __init__(self, stream):
        self.stream = stream

    def write(self, data):
        self.stream.write(data)
        self.stream.flush()

    def writelines(self, datas):
        self.stream.writelines(datas)
        self.stream.flush()

    def __getattr__(self, attr):
        return getattr(self.stream, attr)


sys.stdout = Unbuffered(sys.stdout)

x = 1
while True:
    print(f'{x}: test if this could be killed with shell: true')
    time.sleep(10)
    x += 10

Javascript code

const options = { scriptPath: 'C:\\users\\leona\\iq\\iq-websocket\\python\\botR', shell: true};

const pyTeste = new PythonShell('teste.py', options);

pyTeste
  .on('message', (line: string) => {
    console.log(line);
  })
  .on('stderr', (std: string) => {
    console.log(std);
  })
  .on('error', err => {
    console.log('err');
    console.log(err);
  })
  .on('close', () => {
    console.log('Programa finalizado');
  });

// this function do not work
setTimeout(() => {
  pyTeste.kill();
}, 10000);

Expected behavior
The library to check this situation and kill both the shell where the script is running and the script itself.

Actual behavior
The python program is never killed.

Other Information (please complete the following information):

• OS: Windows10
• Python Version 3.8.7
• Node Version 12.15.0

[Almenon]

Errggg yeah good bug report.

I've encountered this issue before. Killing with cross-platform compatibility is annoying.

Here's how I did it: https://github.com/Almenon/birdseye-vscode/blob/master/src/utilities.ts

since I'm not finding the PID of the spawned process. (PythonShell do not have a pid property)

It doesn't have a pid property but the childProcess has a pid. Try pyTeste.childProcess.pid

[LeonardoRick]

I really missed the .childProcess.pid. This will help a lot.

I just used your function and changed the call I was making to

setTimeout(() => {
  killAll(pyTeste.childProcess.pid);
}, 20000);

The problem is that the program is exiting with an error:

err
PythonShellError: process exited with code 1
    at terminateIfNeeded (C:\Users\leona\iq\iq-websocket\node_modules\python-shell\index.ts:193:27)
    at Socket.<anonymous> (C:\Users\leona\iq\iq-websocket\node_modules\python-shell\index.ts:164:17)
    at Socket.emit (events.js:228:7)
    at Socket.EventEmitter.emit (domain.js:475:20)
    at endReadableNT (_stream_readable.js:1185:12)
    at processTicksAndRejections (internal/process/task_queues.js:81:21) {
  executable: 'py',
  options: null,
  script: 'C:\\users\\leona\\iq\\iq-websocket\\python\\botR\\teste.py',
  args: null,
  exitCode: 1
}

Is there a way to kill it nicely with no errors?

[Almenon]

I would deregister the error handler right before you kill it, so the error is not logged.

[LeonardoRick]

But it sounds like this signal we are sending, are finishing the program in a abrupt way, isn't it? If not, why it's throwing and error and the implemented kill() method on the library don't? I think that maybe there's a way to send a gently signal to finish the program and we are almost achiving that.

[LeonardoRick]

@Almenon, since i'm not finding a way to kill it without throw the error, could you give me an example on how deregsiter only the error listener?

[Almenon]

But it sounds like this signal we are sending, are finishing the program in a abrupt way, isn't it? If not, why it's throwing and error and the implemented kill() method on the library don't? I think that maybe there's a way to send a gently signal to finish the program and we are almost achiving that.

Not exactly. SIGTERM kills "gracefully" - the application has a chance to handle the signal before exiting. Your python code doesn't have any handlers so it simply exits with code 1. Example of handling signals: https://stackoverflow.com/questions/18499497/how-to-process-sigterm-signal-gracefully

since i'm not finding a way to kill it without throw the error, could you give me an example on how deregsiter only the error listener?

I don't remember how to do it exactly. I suggest googling. I googled "node how to unregister handler" and found https://stackoverflow.com/a/23893949/6629672, which may be helpful