How do I set signal handler to multiprocessing.Process? - windows

Question

How can I set signal handler in target function?
multiprocessing.Process (cur_process in GUI) object would created and start when user click start button.
After that when user click stop button, I need to kill process gracefully.(send SIGTERM to cur_process when click stop button)
However, I am using Webdriver, so I want to quit Webdriver before kill process.
So I tried set signal handler in target function (test_main) but does not handle SIGTERM despite click stop button.
How I can set signal handler in Process target function?
import tkinter as tk
from multiprocessing import Process
from tkinter import messagebox
import sys
import signal
import time
import os
from selenium.webdriver.support.wait import WebDriverWait
from selenium import webdriver
from selenium.webdriver.common.by import By
from selenium.webdriver.chrome.options import Options
from selenium.webdriver.support import expected_conditions as EC
def create_driver():
options = Options()
if sys.platform == "darwin":
options.binary_location = '/Applications/Google Chrome Canary.app/Contents/MacOS/Google Chrome Canary'
#options.add_experimental_option("detach", True)
if sys.platform == "win32":
options.binary_location = "C:\\(user_home)\\AppData\\Local\\Google\\Chrome SxS\\Application\\chrome.exe" #location of chrome canary for windows
options.add_argument('--headless')
#options.add_argument('--disable-gpu')
options.add_argument('--reduce-security-for-testing')
options.add_argument('--allow-insecure-localhost')
if sys.platform == "win32":
chromedriver_path = r".\chromedriver"
else:
chromedriver_path = "./chromedriver"
driver = webdriver.Chrome(chromedriver_path, chrome_options=options)
return driver
class GUI(tk.Frame):
def __init__(self, master=None):
super().__init__(master)
self.cur_process = None
self.pack()
self.create_widget()
def create_widget(self):
self.start = tk.Button(self, width=5, padx=10, pady=3)
self.start["text"] = "Start"
self.start["command"] = self.start_event
self.start.grid(row=2, column=2, columnspan=2, padx=4, pady=10)
self.quit = tk.Button(self, width=5, padx=10, pady=3)
self.quit["text"] = "Stop"
self.quit["command"] = self.stop_event
self.quit.grid(row=3, column=2, columnspan=2, padx=4, pady=10)
def start_event(self):
if self.cur_process is None:
self.cur_process = Process(target=test_main) #target function
self.cur_process.start()
def stop_event(self):
if self.cur_process != None:
os.kill(self.cur_process.pid, signal.SIGTERM)
# self.driver.quit()
self.cur_process = None
def test_main(): #target function
# set signal handler to SIGTERM
def k():
print("set new signal handler")
try:
driver.quit()
# then terminate process
except NameError:# driver is not defined
pass # do nothing
sys.exit() # terminate process
signal.signal(signal.SIGTERM, k)
# do something with driver
driver = create_driver()
def gui():
root = tk.Tk()
root.geometry("400x300")
g = GUI(master=root)
g.mainloop()
if __name__ == "__main__":
gui()