Python长期运行流程的龙卷风web服务

Question

我想编写一个在后台处理请求的web服务。该服务将请求放入队列并立即响应客户端。

我在下面的代码中的问题是，BackgroundThread（）。run（）函数中的while循环不起作用。

虽然BackgroundThread.run（）方法中的循环并不像infinite那样工作，但它只进入while循环一次。

谢谢。

代码：

class BackgroundThread(threading.Thread): 

    def __init__(self): 
     threading.Thread.__init__(self) 

    def run(self): 
     global queue 
     while True: 
      item = queue.get() 
      if item is not None: 
       #long running process 
       time.sleep(random.randint(10, 100)/1000.0) 
       print "task", item, "finished" 

queue = Queue.Queue() 

class MyHandler(tornado.web.RequestHandler): 
    @gen.coroutine 
    def get(self): 
     global queue 
     self.write('OK') 
     self.finish() 
     filePath = self.get_arguments("filePath") 
     queue.put(filePath) 
     print queue.qsize() 

if __name__=='__main__': 
    try: 
     BackgroundThread().start() 
     BackgroundThread().start() 
     app = tornado.web.Application([(r'/', MyHandler)]) 
     print("server opened on port : 8000") 
     server = tornado.httpserver.HTTPServer(app) 
     server.bind(8000) 
     server.start(4) # Specify number of subprocesses 
     tornado.ioloop.IOLoop.current().start() 
    except KeyboardInterrupt: 
     print '^C received, shutting down the web server' 
     sys.exit(1) 

Answer 1

我只是加试块除外，因为当队列处于while循环空的，它会得到一个异常，并且不重复。

我得到了答案，这里是代码：

class BackgroundThread(threading.Thread): 
def __init__(self): 
    threading.Thread.__init__(self) 

def run(self): 
    global queue 
    print("qwerqwer0") 
    while 1==1: 
     print("qwerqwer1") 
     print("qwerqwer2") 
     try: 
      item = queue.get() 
      queue.task_done() 
     except Queue.Empty: 
      print("empty") 
      pass 
     if item is not None: 
      print("qwerqwerqwer") 
      #long running process 
      print "task ", item, " finished" 

queue = Queue.Queue() 

class MyHandler(tornado.web.RequestHandler): 
    @gen.coroutine 
    def get(self): 
     global queue 
     self.write('OK') 
     self.finish() 
     filePath = self.get_arguments("filePath") 
     queue.put(filePath) 
     print queue.qsize() 

if __name__=='__main__': 
    try: 
     #BackgroundThread().start() 
     BackgroundThread().start() 
     app = tornado.web.Application([(r'/', MyHandler)]) 
     print("server opened on port : 8000") 
     server = tornado.httpserver.HTTPServer(app) 
     server.bind(8000) 
     server.start(4) # Specify number of subprocesses 
     tornado.ioloop.IOLoop.current().start() 
    except KeyboardInterrupt: 
     print '^C received, shutting down the web server' 
     sys.exit(1)