Fix network discovery error in latest docker version

nginx_proxy/pre_processors/virtual_host_processor.py

@@ -93,15 +93,19 @@ def host_generator(container: DockerContainer, service_id: str = None, known_net
     for name, detail in network_settings["Networks"].items():
         c.add_network(detail["NetworkID"])
         # fix for https://trello.com/c/js37t4ld
-        if detail["Aliases"] is not None:
+        if detail["Aliases"] is not None: # we might use alias
             if detail["NetworkID"] in known_networks and unknown:
                 alias = detail["Aliases"][len(detail["Aliases"]) - 1]
                 ip_address = detail["IPAddress"]
                 network = name
                 if ip_address:
                     break
+        elif detail['NetworkID']:
+            ip_address = detail["IPAddress"]
+            if ip_address:
+                break
     else:
-        raise UnreachableNetwork()
+        raise UnreachableNetwork(c.networks)
 
     for host_config in static_hosts:
         host, location, container_data, extras = _parse_host_entry(host_config)