django channel 如何实时 tail 某个文件

class LogConsumer(WebsocketConsumer):

    def disconnect(self, close_code):
        print('关闭')
        if getattr(self, 'f', None):
            self.f.terminate()

    def receive(self, text_data):
        print(text_data)
        log_file = 'xxxxx.log'

        if not os.path.exists(log_file):
            self.send(json.dumps({
                'key': 0,
                'data': '日志不存在'
            }))
            return
        self.f = subprocess.Popen(
            'tail -f -n 40 {}'.format(log_file),
            stdout=subprocess.PIPE,
            stderr=subprocess.PIPE,
            shell=True,
        )
        p = select.poll()
        p.register(self.f.stdout)
        line_number = 1
        while True:
            if p.poll(1):
                msg = self.f.stdout.readline().decode("utf-8")
                if not msg:
                    raise Exception
                for m in str(msg).splitlines():
                    self.send(json.dumps({'key': line_number,
                                            'data': m + '\n'
                                            }))
                    line_number += 1

这样有一个问题就是会导致这个 consumer 处于 blocking 状态，导致 disconnect 无法被触发，进而无法释放进程

有什么好的解决办法吗？

第 1 条附言 · 2019-02-14 15:25:25 +08:00

没用到channel

class LogConsumer(WebsocketConsumer):
    def __init__(self, *args, **kwargs):
        super(LogConsumer, self).__init__(*args, **kwargs)
        self.processes = []
        self.threads = []

    def disconnect(self, close_code):
        for p in self.processes:
            p.terminate()

        for th in self.threads:
            th.join()

    def receive(self, text_data):
        log_file = 'some_path'

        if not os.path.exists(log_file):
            self.send(json.dumps({
                'key': 0,
                'data': '日志不存在'
            }))
            return
        popen = subprocess.Popen(
            'tail -f -n 40 {}'.format(log_file),
            stdout=subprocess.PIPE,
            stderr=subprocess.PIPE,
            shell=True,
        )
        self.processes.append(popen)

        def output_log():
            line_number = 1
            while True:
                msg = popen.stdout.readline().decode("utf-8")
                if not msg:
                    continue
                for m in str(msg).splitlines():
                    self.send(json.dumps({'key': line_number,
                                        'data': m + '\n'
                                        }))
                    line_number += 1

        tail_thread = threading.Thread(name='log_tail', target=output_log)
        tail_thread.start()

        self.threads.append(tail_thread)

5 条回复 • 2020-01-07 18:27:20 +08:00