ZeroMQ订户不会在单元测试中接收任何数据。为什么？

Question

我无法理解数据的最终位置。

我已经编写了一个测试，以确保我的Publisher类成功发送数据，并且如果我绑定了该数据，则会收到此数据。

该类本身继承自Thread，并公开了publish()方法，我可以调用该方法将数据传递给订阅者，通过Queue()广播。

然而，在我的测试中，数据永远不会到来。我确保使用相同的 端口，我无法想到这里还有什么问题。

我是ZeroMQ新手，但我之前设法让PubSub模式工作。

测试代码：

# Import Built-ins
import time
import json
import queue
from queue import Queue
from threading import Thread

# Import Third-Party
import zmq


def test_publisher_sends_data(self):
    port = 667
    name, topic, data = 'TestNode', 'testing', ['this', 'is', 'data']
    encoded_name = json.dumps(name).encode('utf-8')
    encoded_topic = json.dumps(topic).encode('utf-8')
    encoded_data = json.dumps(data).encode('utf-8')
    expected_result = (encoded_name, encoded_topic, encoded_data)

    publisher = Publisher(port)
    print("starting publisher")
    publisher.start()

    q = Queue()

    def recv(q):
        ctx = zmq.Context()
        zmq_sock = ctx.socket(zmq.SUB)
        print("Connecting to publisher")
        zmq_sock.connect('tcp://127.0.0.1:%s' % port)
        while True:
            print("waiting for data..")
            q.put(zmq_sock.recv_multipart())
            print("data received!")
    t = Thread(target=recv, args=(q,))
    t.start()

    print("sending data via publisher")
    for i in range(5):
        self.assertTrue(publisher.publish(name, topic, data))
        time.sleep(0.1)
    print("checking q for received data..")
    try:
        result = q.get(block=False)
    except queue.Empty:
        self.fail("Queue was empty, no data received!")
    self.assertEqual(expected_result, result)

Publisher班级

# Import Built-Ins
import logging
import json
from queue import Queue
from threading import Thread, Event

# Import Third-Party
import zmq


class Publisher(Thread):
    """Publisher Class which allows publishing data to subscribers.

    The publishing is realized with ZMQ Publisher sockets, and supports publishing
    to multiple subscribers.

    The run() method continuosly checks for data on the internal q, which is fed
    by the publish() method.

    """
    def __init__(self, port, *args, **kwargs):
        """Initialize Instance.
        :param port:
        """
        self.port = port
        self._running = Event()
        self.sock = None
        self.q = Queue()
        super(Publisher, self).__init__(*args, **kwargs)

    def publish(self, node_name, topic, data):
        """Publish the given data to all current subscribers.

        All parameters must be json-serializable objects
        :param data:
        :return:
        """
        message_parts = [json.dumps(param).encode('utf-8')
                         for param in (node_name, topic, data)]
        if self.sock:
            self.q.put(message_parts)
            return True
        else:
            return False

    def join(self, timeout=None):
        self._running.clear()
        try:
            self.sock.close()
        except Exception:
            pass
        super(Publisher, self).join(timeout)

    def run(self):
        self._running.set()
        ctx = zmq.Context()
        self.sock = ctx.socket(zmq.PUB)
        self.sock.bind("tcp://*:%s" % self.port)
        while self._running.is_set():
            if not self.q.empty():
                msg_parts = self.q.get(block=False)
                print("Sending data:", msg_parts)
                self.sock.send_multipart(msg_parts)
            else:
                continue
        ctx.destroy()
        self.sock = None

Answer 1

添加.setsockopt( zmq.SUBSCRIBE, someNonZeroLengthSTRING )
如

记录的默认SUB - 套接字实例没有订阅

（自然） 如果任何传入的消息无法匹配任何字符串，SUB - 订阅，本地.recv()自然不会收到这样的。

鉴于您的代码没有明确订阅，没有这样的消息，可以满足主题过滤处理条件，Q.E.D。

最好的下一步：

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