線程掛起使用FTP列表與Python

我使用ftplib連接並從FTP服務器獲取文件列表。我遇到的問題是連接不時掛起，我不知道爲什麼。我使用線程作爲守護進程運行python腳本。明白我的意思：線程掛起使用FTP列表與Python

def main(): 
signal.signal(signal.SIGINT, signal_handler) 

    app.db = MySQLWrapper() 
    try: 
     app.opener = FTP_Opener() 
     mainloop = MainLoop() 

     while not app.terminate: 
      # suspend main thread until the queue terminates 
      # this lets to restart the queue automatically in case of unexpected shutdown 
      mainloop.join(10) 
      while (not app.terminate) and (not mainloop.isAlive()): 
       time.sleep(script_timeout) 
       print time.ctime(), "main: trying to restart the queue" 
       try: 
        mainloop = MainLoop() 
       except Exception: 
        time.sleep(60) 

    finally: 
     app.db.close() 
     app.db = None 
     app.opener = None 
     mainloop = None 
     try: 
      os.unlink(PIDFILE) 
     except: 
      pass 
     # give other threads time to terminate 
     time.sleep(1) 
     print time.ctime(), "main: main thread terminated"

MainLoop語句（）對FTP連接的一些功能，從服務器下載特定文件和斷開。

以下是我獲取文件的列表：

file_list = app.opener.load_list()

以及如何FTP_Opener.load_list（）函數如下：

def load_list(self): 
    attempts = 0 
    while attempts<=ftp_config.load_max_attempts: 
     attempts += 1 
     filelist = [] 
     try: 
      self._connect() 
      self._chdir() 
      # retrieve file list to 'filelist' var 
      self.FTP.retrlines('LIST', lambda s: filelist.append(s)) 

      filelist = self._filter_filelist(self._parse_filelist(filelist)) 

      return filelist 
     except Exception: 
      print sys.exc_info() 
      self._disconnect() 
      sleep(0.1) 

    print time.ctime(), "FTP Opener: can't load file list" 
    return []

爲什麼有時FTP連接掛起，如何監控呢？所以如果發生了，我想以某種方式終止線程並開始一個新線程。

感謝

來源

2012-10-16 KennyPowers

哦'load_max_attempts = 10' – KennyPowers