Adding extra_hosts param to docker-compose

docs/yml.md

@@ -344,7 +344,7 @@ dns_search:
 
 ### devices
 
-List of device mappings.  Uses the same format as the `--device` docker 
+List of device mappings.  Uses the same format as the `--device` docker
 client create option.
 
 ```
@@ -388,3 +388,13 @@ read_only: true
 - [Command line reference](cli.md)
 - [Compose environment variables](env.md)
 - [Compose command line completion](completion.md)
+
+
+### extra_hosts
+
+Add custom entry in /etc/hosts file.
+
+```
+extra_hosts:
+  mymemcacheserver: 192.168.0.10
+```

tests/integration/service_test.py

@@ -230,6 +230,15 @@ def test_create_container_with_volumes_from(self):
         self.assertIn(volume_container_2.id,
                       host_container.get('HostConfig.VolumesFrom'))
 
+    def test_create_container_with_extra_hosts(self):
+        extra_hosts = {'myserver': '192.168.2.90',
+                     'myserver2': '10.55.32.12'}
+        service = self.create_service('database', extra_hosts=extra_hosts)
+        container = service.create_container()
+        service.start_container(container)
+        self.assertEqual(container.get('HostConfig.ExtraHosts'),
+                         ['myserver:192.168.2.90', 'myserver2:10.55.32.12'])
+
     def test_recreate_containers(self):
         service = self.create_service(
             'db',