如何使用日誌記錄模塊避免重複輸出

Question

我正在使用日誌記錄模塊將腳本中用於打印語句的內容輸出到控制檯和日誌文件。但是，每次運行腳本時，輸出都會附加到控制檯和日誌中打印的內容上，而不是覆蓋那裏的內容。例如，我第一次運行該腳本我在控制檯中看到這個輸出和日誌文件：

This print statement is going to both the console and the log 
The year is: 2015 

我第二次運行該腳本，我得到這個在控制檯：

This print statement is going to both the console and the log 
This print statement is going to both the console and the log 
The year is: 2015 
The year is: 2015 

第三次：

This print statement is going to both the console and the log 
This print statement is going to both the console and the log 
This print statement is going to both the console and the log 
The year is: 2015 
The year is: 2015 
The year is: 2015 

等和日誌文件將追加讓我結束了：

This print statement is going to both the console and the log 
The year is: 2015 
This print statement is going to both the console and the log 
This print statement is going to both the console and the log 
The year is: 2015 
The year is: 2015 
This print statement is going to both the console and the log 
This print statement is going to both the console and the log 
This print statement is going to both the console and the log 
The year is: 2015 
The year is: 2015 
The year is: 2015 

我要的是兩者的日誌文件和控制檯只給我下面的，無論多少次，我重新運行該腳本：

This print statement is going to both the console and the log 
The year is: 2015 

注：只有這樣，我目前能得到什麼，我想要在腳本運行之間關閉Python，但這不是一個實際的解決方案。

我已經嘗試使用沖水（），並嘗試做這樣的事情：

logger = logging.basicConfig(filemode='w', level=logging.DEBUG) 

，但我一直沒能得到它與我的代碼工作。有人可以幫忙嗎？這裏是我的代碼：

import inspect 
import logging 
import datetime 

def getDate(): 
    now = datetime.datetime.now() 
    m = now.month 
    d = now.day 
    y = str(now.year) 
    if m < 10: 
     m = "0"+str(m) 
    else: 
     m = str(m) 
    if d < 10: 
     d = "0"+str(d) 
    else: 
     d = str(d) 
    y = y[2:] 
    formatted_date = m+d+y 
    return formatted_date 

def function_logger(file_level, console_level = None): 
    function_name = inspect.stack()[1][3] 
    logger = logging.getLogger(function_name) 
    logger.setLevel(logging.DEBUG) #By default, logs all messages 

    if console_level != None: 
     ch = logging.StreamHandler() #StreamHandler logs to console 
     ch.setLevel(console_level) 
     ch_format = logging.Formatter('%(message)s') 
     ch.setFormatter(ch_format) 
     logger.addHandler(ch) 

    log_name = 'Test_log' + getDate() + '.log' 
    fh = logging.FileHandler(log_name.format(function_name)) 
    fh.setLevel(file_level) 
    fh_format = logging.Formatter('%(message)s') 
    fh.setFormatter(fh_format) 
    logger.addHandler(fh) 
    return logger 

def f1(): 
    global logger 
    year = '2015' 
    logger.info("The year is: %s" % (year)) 

def main(): 

    global logger 
    logger = function_logger(logging.INFO, logging.INFO) 
    logger.info('This print statement is going to both the console and the log') 
    f1() 
    logging.shutdown() 

if __name__ == '__main__': 
    main() 

Answer 1

感謝盧卡斯·格拉夫，這裏是我固定的代碼做正是我想要的：

def function_logger(file_level, console_level = None): 
    function_name = inspect.stack()[1][3] 
    logger = logging.getLogger(function_name) 
    logger.setLevel(logging.DEBUG) #By default, logs all messages 
    log_name = 'Test_log_' + getDate() + '.log' 

    if not logger.handlers: 
     if console_level != None: 
      ch = logging.StreamHandler() #StreamHandler logs to console 
      ch.setLevel(console_level) 
      ch_format = logging.Formatter('%(message)s') 
      ch.setFormatter(ch_format) 
      logger.addHandler(ch) 

     fh = logging.FileHandler(log_name.format(function_name), mode='w') 
     fh.setLevel(file_level) 
     fh_format = logging.Formatter('%(message)s') 
     fh.setFormatter(fh_format) 
     logger.addHandler(fh) 

    return logger 

有三件事情需要注意有關此修復程序：

1：我移動測試條件下都addHandlers：

if not logger.handlers: 

2：我添加模式= 'W' 到Filhandler：

fh = logging.FileHandler(log_name.format(function_name), mode='w') 

3：我清除了處理器在主要底部（）：

logger.handlers = []