queue.py 文件源码

def pop(self, timeout=0):
        """Pop a request"""
        if timeout > 0:
            data = self.server.brpop(self.key, timeout=timeout)
            if isinstance(data, tuple):
                data = data[1]
        else:
            data = self.server.rpop(self.key)
        if data:
            cb, url = data.split('--', 1)
            try:
                cb = getattr(self.spider, str(cb))
                return Request(url=url, callback=cb)
            except AttributeError:
                raise ValueError("Method %r not found in: %s" % (cb, self.spider))