fixup! Fix: Race condition in DockerContainerTestCase (#6587)

test/docker_container_test_case.py

@@ -87,34 +87,30 @@ def _create_container(cls, image: str, container_port: int, **kwargs) -> Netloc:
         try:
             time_it = datetime.now()
             container_info = cls._docker.api.inspect_container(container.id)
-            network_settings = container_info['NetworkSettings']
             if is_sibling:  # no coverage
-                container_ip = network_settings['IPAddress']
+                container_ip = container_info['NetworkSettings']['IPAddress']
                 assert isinstance(container_ip, str)
                 endpoint = (container_ip, container_port)
                 log.info('Launched sibling container %s from image %s, listening on %s:%i',
                          container.name, image, container_ip, container_port)
             else:
-                retries = 0
-                ports = network_settings['Ports']
-                while len(ports[f'{container_port}/tcp']) < 1:
-                    if (datetime.now() - time_it).seconds > 3:
-                        # Wait for the published ports of the container that's
-                        # supposedly running, otherwise giveup (let it fail).
-                        log.error('Unreachable TCP port %s for container %s',
-                                  container_port, container.name)
+                seconds = 0.0
+                while True:
+                    ports = container_info['NetworkSettings']['Ports'][f'{container_port}/tcp']
+                    if len(ports) > 0:
                         break
-                    time.sleep(.33)
-                    container_info = cls._docker.api.inspect_container(container.id)
-                    ports = container_info['NetworkSettings']['Ports']
-                    retries += 1
-                milisecs = (datetime.now() - time_it).microseconds / 1000
-                port = one(ports[f'{container_port}/tcp'])
+                    elif seconds > 3:
+                        raise RuntimeError('Unreachable TCP port', container_port, container.name)
+                    else:
+                        time.sleep(.33)
+                        container_info = cls._docker.api.inspect_container(container.id)
+                        seconds = (datetime.now() - time_it).total_seconds()
+                port = one(ports)
                 host_ip = port['HostIp']
                 host_port = int(port['HostPort'])
-                log.info('Launched container %s from image %s after %dms (retries %d), '
+                log.info('Launched container %s from image %s after %.3fs, '
                          'with container port %s mapped to %s:%i on the host',
-                         container.name, image, milisecs, retries, container_port, host_ip, host_port)
+                         container.name, image, seconds, container_port, host_ip, host_port)
                 endpoint = (host_ip, host_port)
         except BaseException:  # no coverage
             container.kill()