將輸出從Python記錄器重定向到tkinter小部件

Question

花了一些時間重定向標准輸出並將輸出記錄到tkinter文本小部件后，我決定需要一些幫助。 我的代碼如下：

#!/usr/bin/env python
from Tkinter import *
import logging
from threading import Thread

class IODirector(object):
    def __init__(self,text_area):
        self.text_area = text_area

class StdoutDirector(IODirector):
    def write(self,str):
        self.text_area.insert(END,str)
    def flush(self):
        pass

class App(Frame):

    def __init__(self, master):
        self.master = master
        Frame.__init__(self,master,relief=SUNKEN,bd=2)
        self.start()

    def start(self):
        self.master.title("Test")
        self.submit = Button(self.master, text='Run', command=self.do_run, fg="red")
        self.submit.grid(row=1, column=2)
        self.text_area = Text(self.master,height=2.5,width=30,bg='light cyan')
        self.text_area.grid(row=1,column=1)

    def do_run(self):
        t = Thread(target=print_stuff)
        sys.stdout = StdoutDirector(self.text_area)
        t.start()

def print_stuff():
    logger = logging.getLogger('print_stuff')
    logger.info('This will not show')
    print 'This will show'
    print_some_other_stuff()

def print_some_other_stuff():
    logger = logging.getLogger('print_some_other_stuff')
    logger.info('This will also not show')
    print 'This will also show'

def main():    
    logger = logging.getLogger('main')
    root = Tk()
    app = App(root)
    root.mainloop() 

if __name__=='__main__':
    main()

我知道可以基於文本窗口小部件定義一個新的日志記錄處理程序，但是我無法使其正常工作。 函數“ print_stuff”實際上只是許多不同函數的包裝，所有這些函數都有自己的記錄器。 我需要幫助定義一個新的“全局”日志記錄處理程序，以便可以從具有自己記錄器的每個函數中實例化它。 任何幫助深表感謝。

Answer 1

只是為了確保我理解正確：

您想將日志記錄消息都打印到STDout和Tkinter文本小部件中，但是日志記錄不會在標准控制台中打印。

如果確實是您的問題，請按照以下步驟操作。

首先，讓我們在Tkinter中創建一個非常簡單的控制台，它實際上可以是任何文本小部件，但出於完整性考慮，我將其包括在內：

class LogDisplay(tk.LabelFrame):
"""A simple 'console' to place at the bottom of a Tkinter window """
    def __init__(self, root, **options):
        tk.LabelFrame.__init__(self, root, **options);

        "Console Text space"
        self.console = tk.Text(self, height=10)
        self.console.pack(fill=tk.BOTH)

現在，讓我們重寫日志記錄處理程序，以重定向到參數中的控制台，並且仍然自動打印到STDout：

class LoggingToGUI(logging.Handler):
""" Used to redirect logging output to the widget passed in parameters """
    def __init__(self, console):
        logging.Handler.__init__(self)

        self.console = console #Any text widget, you can use the class above or not

    def emit(self, message): # Overwrites the default handler's emit method
        formattedMessage = self.format(message)  #You can change the format here

        # Disabling states so no user can write in it
        self.console.configure(state=tk.NORMAL)
        self.console.insert(tk.END, formattedMessage) #Inserting the logger message in the widget
        self.console.configure(state=tk.DISABLED)
        self.console.see(tk.END)
        print(message) #You can just print to STDout in your overriden emit no need for black magic

希望能幫助到你。

Answer 2

這是一個完全修訂的答案，可以滿足您的需求。 我試圖指出問題中代碼的哪些行已更改以及在哪里添加了新行。

默認情況下，內置的logger.StreamHandler處理程序類將消息輸出到sys.stderr ，因此logger.StreamHandler它們也將sys.stdout重定向到文本小部件，則需要構造一個新的logger，並為其設置一個自定義控制台處理程序。 由於您希望將其應用於模塊中的所有記錄器，因此需要將此設置應用於所有其他命名記錄器將繼承其設置的無名“根”記錄器。

from Tkinter import *
import logging
from threading import Thread

class IODirector(object):
    def __init__(self, text_area):
        self.text_area = text_area

class StdoutDirector(IODirector):
    def write(self, msg):
        self.text_area.insert(END, msg)
    def flush(self):
        pass

class App(Frame):
    def __init__(self, master):
        self.master = master
        Frame.__init__(self, master, relief=SUNKEN, bd=2)
        self.start()

    def start(self):
        self.master.title("Test")
        self.submit = Button(self.master, text='Run', command=self.do_run, fg="red")
        self.submit.grid(row=1, column=2)
        self.text_area = Text(self.master, height=2.5, width=30, bg='light cyan')
        self.text_area.grid(row=1, column=1)

    def do_run(self):
        t = Thread(target=print_stuff)
        sys.stdout = StdoutDirector(self.text_area)
        # configure the nameless "root" logger to also write           # added
        # to the redirected sys.stdout                                 # added
        logger = logging.getLogger()                                   # added
        console = logging.StreamHandler(stream=sys.stdout)             # added
        logger.addHandler(console)                                     # added
        t.start()

def print_stuff():
    logger = logging.getLogger('print_stuff') # will inherit "root" logger settings
    logger.info('This will now show')                                  # changed
    print 'This will show'
    print_some_other_stuff()

def print_some_other_stuff():
    logger = logging.getLogger('print_some_other_stuff') # will inherit "root" logger settings
    logger.info('This will also now show')                             # changed
    print 'This will also show'

def main():
    logging.basicConfig(level=logging.INFO) # enable logging           # added
    root = Tk()
    app = App(root)
    root.mainloop()

if __name__=='__main__':
    main()