Python 3.6 Tkinter 和多重处理

Question

一些背景故事，该应用程序可以连接超过 45 个设备并通过 Netmiko 执行一些 SSH 命令。这是两个 GUI 窗口。第一个询问您的用户名/密码以及用户的具体输入。提交后，会弹出另一个带有按钮的 GUI 窗口。选中此按钮后，将运行功能的命令。我已经设置了一个 GUI，使其非常用户友好，希望我们的服务台能够使用它。

我已经让它可以工作了，但是需要 10 分钟以上才能完成与设备的 45 个 SSH session 。我开始研究一些多线程或多进程的方法，但未能让它们发挥作用。

如果您能获得多处理/线程以减少处理时间，我们将不胜感激。目标是同时运行 5 到 10 个 SSH session ，以帮助限制等待应用程序的时间。还可能在进程运行时阻止第二个 GUI 窗口卡住。

下面是需要 10 分钟以上才能完成的工作代码。我从一个单独的 python 文件导入“a_devices”，仅供引用。

#!/usr/bin/env python3
import netmiko
import sys
import os
from netmiko import ConnectHandler
from tkinter import *
import tkinter
from tkinter import ttk
import threading
from multiprocessing import Process
from multiprocessing import Pool
import time
import getpass
from Dictionaries import *
from netmiko.ssh_exception import NetMikoTimeoutException, NetMikoAuthenticationException
from paramiko.ssh_exception import SSHException
from datetime import datetime

vpntermination = None

username = input('Username: ')
password = getpass.win_getpass(prompt='Password: ', stream=None)

# Sends outputs to Text widgets
class StdoutRedirector(object):
  def __init__(self,text_widget):
    self.text_space = text_widget
  def write(self,string):
    self.text_space.insert('end', string)
    self.text_space.see('end')

class Input_Window_GUI():
  def __init__(self, master): 
    self.master = master
    master.wm_title("VPN Termination Application")
    self.label = Label(master, text="User to be terminated:", font=24).grid(row=0, column=2, columnspan=2)
    self.master.geometry("650x600")
    self.master.lift()
    self.master.attributes('-topmost',True)
    self.master.after_idle(master.attributes,'-topmost',False)
    self.master.grid_columnconfigure(3, minsize=250, weight=1)

    self.textBoxFrame = tkinter.Frame(master)
    self.textBoxFrame.grid(row=5, column=3, columnspan=1, sticky=E+W)

    self.textbox=Text(self.textBoxFrame)
    self.textbox.grid(row=5, column=3, sticky=W, pady=2)

    sys.stdout = StdoutRedirector(self.textbox)

    self.e1 = Entry(self.master)
    self.e1.insert(10,"")
    self.e1.grid(row=1, column=2, columnspan=2)

    self.submitButtonFrame = tkinter.Frame(master)
    self.addButtonFrame = tkinter.Frame(master)
    self.clearButtonFrame = tkinter.Frame(master)
    self.submitButtonFrame.grid(row=6, column=1, columnspan=1)
    self.addButtonFrame.grid(row=2, column=3, columnspan=1)
    self.clearButtonFrame.grid(row=2, column=4, columnspan=1)

    self.buttonFrameClose = tkinter.Frame(master)
    self.buttonFrameClose.grid(row=6, column=4)

    self.submit_button = Button(self.submitButtonFrame, text='Submit Changes', command=self.Submit_Application, height = 3, width = 15).grid(row=2, column=1, sticky=W, pady=2)
    self.add_user_button = Button(self.addButtonFrame, text='Add User for Termination', command=self.Add_User, height = 3, width = 25).grid(row=2, column=2, sticky=W, pady=2)
    self.close_app_button = Button(self.buttonFrameClose, text='Close App', command=self.Close_All, height = 3, width = 15).grid(row=6, column=3, sticky=E, pady=2)
    self.clear_user_button = Button(self.clearButtonFrame, text='Clear All', command=self.Clear_User, height = 3, width = 15).grid(row=2, column=3, sticky=W, pady=2)


  def Add_User(self):
    try:
        if not self.e1.get():# empty! (empty string is false value)
            print('Ooops, nothing entered, please enter an acceptible username.')
        elif self.e1.get() == " ":
            print('Ooops, nothing entered, please enter an acceptible username.')
            e1.delete(0,END)
        else:
            user = self.e1.get()
            global vpntermination #Had to change to global so it could be passed throughout the multiple windows.
            vpntermination = user
            print("User staged for Termination: %s" % (user))
            print("")
            self.e1.delete(0,END)
            return vpntermination
    except ValueError:
      print('Incorrect entry, please reenter username.')
      self.e1.delete(0,END)
      return 'Value'    
    except TypeError:
      print('Incorrect entry, please reenter username.')
      self.e1.delete(0,END)
      return 'Type'

  def Clear_User(self):
    vpntermination = None
    print("User cleared, readd User.")
    print("")

  def Close_All(self):
    self.master.destroy()
    sys.exit(1)

  #Closes initial tkinter window and continues the code. 
  def Submit_Application(self):
    self.master.after(1000, lambda: self.master.destroy())

class Output_Window_GUI:
  def __init__(self, root):
    self.root = root
    root.wm_title("VPN Termination Output")
    self.label = Label(root, text="Output:", font=24).grid(row=0, column=2, columnspan=2)
    self.root.geometry("650x600")
    self.root.lift()
    self.root.attributes('-topmost',True)
    self.root.after_idle(root.attributes,'-topmost',False)

    self.textBoxFrame = tkinter.Frame(root)
    self.textBoxFrame.grid(row=5, column=3, columnspan=1, sticky=E+W)

    self.textbox=Text(self.textBoxFrame)
    self.textbox.grid(row=5, column=3, sticky=W, pady=2)

    #Calls the class to send CLI output to Textbox
    sys.stdout = StdoutRedirector(self.textbox)

    self.buttonFrameClose = tkinter.Frame(root)
    self.buttonFrameClose.grid(row=6, column=3)
    self.buttonFrame = tkinter.Frame(root)
    self.buttonFrame.grid(row=2, column=2, columnspan=3)
    self.close_all_button = Button(self.buttonFrameClose, text='Close App', command=self.Close_All, height = 3, width = 15).grid(row=2, column=1, sticky=W, pady=4)
    self.start_button = Button(self.buttonFrame, text='Send Commands', command=self.Start_Commands, height = 3, width = 15).grid(row=2, column=1, sticky=W, pady=4)

  def task():
    root.after(2000, task)

  def Close_All(self):
    self.root.destroy()
    sys.exit(1)

  def Start_Commands(self):
    print('VPN Termination Commands are in process for User: ' + vpntermination +'....please wait.')
    print('')
    start_time = datetime.now()
    for a_device in all_firewalls:
      per_fw_start_time = datetime.now()
      try:
        net_connect = ConnectHandler(**a_device)
        hostname = net_connect.send_command("show hostname") #Used to store Hostname.
        output = net_connect.send_command("vpn-sessiondb logoff name " + str(vpntermination) +  " noconfirm") #Used for vpn termination command.
        print('\n******* Output for device ' + hostname + ' *******' )
        print(output)
        print('')
        per_fw_end_time = datetime.now()
        per_fw_total_time = per_fw_end_time - per_fw_start_time
        print("******* " + hostname + " {0} *******".format(a_device['ip'])+ " took " + str(per_fw_total_time) + " to process.")
        print('')
        net_connect.disconnect() #Hoping to speed up process time within multi-threading issues.
      except (NetMikoTimeoutException, NetMikoAuthenticationException) as e: #Handles timeout errors.
        print("Could not connect to {}, due to {}", e)
        print('')

    end_time = datetime.now()
    total_time = end_time - start_time
    print('\nTotal process time: ' + str(total_time))

def main():

  #tkinter GUI that adds user for termination.
  master = Tk()
  my_gui = Input_Window_GUI(master)
  master.mainloop()  

  #tkinter GUI that starts the user being terminated on all devices.
  root=Tk()
  out_gui = Output_Window_GUI(root)
  root.mainloop()


if __name__ == '__main__':
  main()

Answer 1

你可以做的是创建一个 multiprocessing.Queue作为全局变量和单独的进程使用 multiprocessing.Popen 在运行mainloop之前.

您在 Popen 中使用的函数(在单独的进程中运行)应等待 Queue 上的消息并对它们采取行动。这个过程完成了真正的工作。

同时，GUI 将命令(例如，命令和用户名的二元组，如 ('delete', 'foo@bar') )提供以删除用户)和数据到 Queue 中。基于用户输入。它还应该使用 after回调来查询队列并处理来自其他进程的任何响应。

关于风格的一些注释。

• Python 中的类名通常以大写字母开头。函数和方法名称应该小写。请参阅PEP8 .
• 由于您正在运行 GUI，因此使用 message boxes 会更好。通知用户错误而不是打印语句。根据操作系统和程序的启动方式，用户可能会也可能看不到打印输出。
• 使用from <module> import *通常不被认为是好的做法。在这种情况下，我建议 import tkinter as tk .