From e75a03fd6d744a96d84179eadfcc47301ca968c7 Mon Sep 17 00:00:00 2001
From: Viktor Adam <rycus86@gmail.com>
Date: Fri, 12 Jan 2018 22:18:47 +0000
Subject: [PATCH] Fix regression on API < 1.25

Signed-off-by: Viktor Adam <rycus86@gmail.com>
---
 docker/api/service.py                     |  9 ++++++++-
 tests/integration/models_services_test.py | 24 +++++++++++++++++++++++
 2 files changed, 32 insertions(+), 1 deletion(-)

diff --git a/docker/api/service.py b/docker/api/service.py
index 86f4b073..1a8b8b5b 100644
--- a/docker/api/service.py
+++ b/docker/api/service.py
@@ -137,6 +137,8 @@ class ServiceApiMixin(object):
         auth_header = auth.get_config_header(self, registry)
         if auth_header:
             headers['X-Registry-Auth'] = auth_header
+        if utils.version_lt(self._version, '1.25'):
+            networks = networks or task_template.pop('Networks', None)
         data = {
             'Name': name,
             'Labels': labels,
@@ -411,7 +413,12 @@ class ServiceApiMixin(object):
 
         if networks is not None:
             converted_networks = utils.convert_service_networks(networks)
-            data['TaskTemplate']['Networks'] = converted_networks
+            if utils.version_lt(self._version, '1.25'):
+                data['Networks'] = converted_networks
+            else:
+                data['TaskTemplate']['Networks'] = converted_networks
+        elif utils.version_lt(self._version, '1.25'):
+            data['Networks'] = current.get('Networks')
         elif data['TaskTemplate'].get('Networks') is None:
             current_task_template = current.get('TaskTemplate', {})
             current_networks = current_task_template.get('Networks')
diff --git a/tests/integration/models_services_test.py b/tests/integration/models_services_test.py
index ca8be48d..b4df745e 100644
--- a/tests/integration/models_services_test.py
+++ b/tests/integration/models_services_test.py
@@ -179,6 +179,30 @@ class ServiceTest(unittest.TestCase):
         service.reload()
         assert not service.attrs['Spec'].get('Labels')
 
+    def test_update_retains_networks(self):
+        client = docker.from_env(version=TEST_API_VERSION)
+        network_name = helpers.random_name()
+        network = client.networks.create(
+            network_name, driver='overlay'
+        )
+        service = client.services.create(
+            # create arguments
+            name=helpers.random_name(),
+            networks=[network.id],
+            # ContainerSpec arguments
+            image="alpine",
+            command="sleep 300"
+        )
+        service.update(
+            # create argument
+            name=service.name,
+            # ContainerSpec argument
+            command="sleep 600"
+        )
+        service.reload()
+        networks = service.attrs['Spec']['TaskTemplate']['Networks']
+        assert networks == [{'Target': network.id}]
+
     def test_scale_service(self):
         client = docker.from_env(version=TEST_API_VERSION)
         service = client.services.create(