Change format in which hosts are being stored for Swarm services

Signed-off-by: Michael Hankin <mhank@users.noreply.github.com>

docker/types/services.py

@@ -137,7 +137,7 @@ class ContainerSpec(dict):
         if labels is not None:
             self['Labels'] = labels
         if hosts is not None:
-            self['Hosts'] = format_extra_hosts(hosts)
+            self['Hosts'] = format_extra_hosts(hosts, task=True)
 
         if mounts is not None:
             parsed_mounts = []

docker/utils/utils.py

@@ -564,9 +564,15 @@ def format_environment(environment):
     return [format_env(*var) for var in six.iteritems(environment)]
 
 
-def format_extra_hosts(extra_hosts):
+def format_extra_hosts(extra_hosts, task=False):
+    # Use format dictated by Swarm API if container is part of a task
+    if task:
+        return [
+            '{} {}'.format(v, k) for k, v in sorted(six.iteritems(extra_hosts))
+        ]
+
     return [
-        '{} {}'.format(v, k) for k, v in sorted(six.iteritems(extra_hosts))
+        '{}:{}'.format(k, v) for k, v in sorted(six.iteritems(extra_hosts))
     ]
 
 

tests/unit/models_containers_test.py

@@ -141,7 +141,7 @@ class ContainerCollectionTest(unittest.TestCase):
                 'Dns': ['8.8.8.8'],
                 'DnsOptions': ['foo'],
                 'DnsSearch': ['example.com'],
-                'ExtraHosts': ['1.2.3.4 foo'],
+                'ExtraHosts': ['foo:1.2.3.4'],
                 'GroupAdd': ['blah'],
                 'IpcMode': 'foo',
                 'KernelMemory': 123,