python - 为什么我无法在 python 中 ping docker 容器？

Question

我有一个用 python docker 库制作的 docker 容器，如下所示:

docker_client.containers.run(docker_image, detach=True, ports={'80/tcp': 83})

我在 python 中启动它并随后运行测试请求:

r = requests.get("http://localhost:83")

我收到连接错误:

requests.exceptions.ConnectionError: ('Connection aborted.', RemoteDisconnected('Remote end closed connection without response',))

发生这种情况时，应用程序退出，但 docker 容器仍在运行，因此我尝试运行 curl localhost:83 并且成功，没有问题。

这是怎么回事？(顺便说一句，这是在 macOS 上)

Answer 1

您的问题是您运行容器并且不等待服务启动。您应该等待服务启动。您可以使用如下所示的内容

def wait_net_service(server, port, timeout=None):
    """ Wait for network service to appear 
        @param timeout: in seconds, if None or 0 wait forever
        @return: True of False, if timeout is None may return only True or
                 throw unhandled network exception
    """
    import socket
    import errno

    s = socket.socket()
    if timeout:
        from time import time as now
        # time module is needed to calc timeout shared between two exceptions
        end = now() + timeout

    while True:
        try:
            if timeout:
                next_timeout = end - now()
                if next_timeout < 0:
                    return False
                else:
                    s.settimeout(next_timeout)

            s.connect((server, port))

        except socket.timeout, err:
            # this exception occurs only if timeout is set
            if timeout:
                return False

        except socket.error, err:
            # catch timeout exception from underlying network library
            # this one is different from socket.timeout
            if type(err.args) != tuple or err[0] != errno.ETIMEDOUT:
                raise
        else:
            s.close()
            return True

然后将您的代码更新为

docker_client.containers.run(docker_image, detach=True, ports={'80/tcp': 83})
wait_net_service("localhost", 83, 10)
r = requests.get("http://localhost:83")

PS:代码取自https://code.activestate.com/recipes/576655-wait-for-network-service-to-appear/