Added support for restart_policy parameter

This patch adds the restart_policy parameter to services. The parameter
is passed to the Docker API when starting containers. Its recognized values
are the same as in the Docker CLI ("always" and "on-failure[:max-retry]").

For future compatibility, the policy can also be specified as a
dictionary, which is passed directly to the Docker API (after converting
the keys to CamelCase).

This feature seems to have been requested at least in issue docker#478.

Signed-off-by: Kenneth Falck <kennu@iki.fi>

docs/yml.md

@@ -157,3 +157,14 @@ domainname: foo.com
 mem_limit: 1000000000
 privileged: true
 ```
+
+### restart_policy
+
+Specify the container restart policy using the same syntax as the Docker CLI.
+Supported values are "no", "always" and "on-failure[:max-retry]". The default
+is to have no restart policy.
+
+```
+restart_policy: "always"
+restart_policy: "on-failure:3"
+```

fig/service.py

@@ -15,7 +15,7 @@
 log = logging.getLogger(__name__)
 
 
-DOCKER_CONFIG_KEYS = ['image', 'command', 'hostname', 'domainname', 'user', 'detach', 'stdin_open', 'tty', 'mem_limit', 'ports', 'environment', 'dns', 'volumes', 'entrypoint', 'privileged', 'volumes_from', 'net', 'working_dir']
+DOCKER_CONFIG_KEYS = ['image', 'command', 'hostname', 'domainname', 'user', 'detach', 'stdin_open', 'tty', 'mem_limit', 'ports', 'environment', 'dns', 'volumes', 'entrypoint', 'privileged', 'volumes_from', 'net', 'working_dir', 'restart_policy']
 DOCKER_CONFIG_HINTS = {
     'link'      : 'links',
     'port'      : 'ports',
@@ -24,6 +24,7 @@
     'privilige' : 'privileged',
     'volume'    : 'volumes',
     'workdir'   : 'working_dir',
+    'restart'   : 'restart_policy',
 }
 
 VALID_NAME_CHARS = '[a-zA-Z0-9]'
@@ -262,7 +263,7 @@ def start_container(self, container=None, intermediate_container=None, **overrid
         net = options.get('net', 'bridge')
         dns = options.get('dns', None)
 
-        container.start(
+        start_options = dict(
             links=self._get_links(link_to_self=options.get('one_off', False)),
             port_bindings=port_bindings,
             binds=volume_bindings,
@@ -271,6 +272,10 @@ def start_container(self, container=None, intermediate_container=None, **overrid
             network_mode=net,
             dns=dns,
         )
+        restart_policy = parse_restart_policy(options.get('restart_policy', None))
+        if restart_policy:
+            start_options['restart_policy'] = restart_policy
+        container.start(**start_options)
         return container
 
     def start_or_create_containers(self, insecure_registry=False):
@@ -376,7 +381,7 @@ def _get_container_create_options(self, override_options, one_off=False):
             container_options['image'] = self._build_tag_name()
 
         # Delete options which are only used when starting
-        for key in ['privileged', 'net', 'dns']:
+        for key in ['privileged', 'net', 'dns', 'restart_policy']:
             if key in container_options:
                 del container_options[key]
 
@@ -534,3 +539,29 @@ def resolve_env(key, val):
         return key, os.environ[key]
     else:
         return key, ''
+
+
+def parse_restart_policy(restart_policy):
+    """
+    Convert CLI/YML restart policy to a Docker API compatible dict.
+    """
+    # Support a few different alternative syntaxes for restart policy
+    if not restart_policy or restart_policy == 'no':
+        # No policy
+        return None
+    elif isinstance(restart_policy, dict):
+        # Convert specified dict keys to CamelCase so
+        # {'name':'on-failure', 'maximum_retry_count':3} becomes
+        # {'Name':'on-failure', 'MaximumRetryCount':3} for Docker API
+        return dict([(re.sub(r'(?:^|_)([a-zA-Z])', lambda m: m.group(1).upper(), k), v) for (k, v) in restart_policy.items()])
+    elif re.match(r'^on-failure:\s*', restart_policy):
+        # Convert "on-failure:<max-retry>" into proper Docker API syntax
+        return {
+            'Name': 'on-failure',
+            'MaximumRetryCount': int(re.sub(r'^on-failure:\s*', '', restart_policy)),
+        }
+    else:
+        # Use specified string as the Name parameter
+        return {
+            'Name': restart_policy,
+        }

tests/fixtures/restart-policy-figfile/fig.yml

@@ -0,0 +1,4 @@
+service:
+  image: busybox:latest
+  command: sleep 5
+  restart_policy: on-failure:3

tests/integration/cli_test.py

@@ -237,6 +237,16 @@ def test_run_service_with_environement_overridden(self, _):
         # make sure a value with a = don't crash out
         self.assertEqual('moto=bobo', container.environment['allo'])
 
+    @patch('dockerpty.start')
+    def test_run_service_with_restart_policy(self, __):
+        self.command.base_dir = 'tests/fixtures/restart-policy-figfile'
+        self.command.dispatch(['up', '-d', 'service'], None)
+        service = self.project.get_service('service')
+        containers = service.containers(stopped=True)
+        container = service.containers(stopped=True)[0].inspect()
+        self.assertEqual(container['HostConfig']['RestartPolicy']['Name'], 'on-failure')
+        self.assertEqual(container['HostConfig']['RestartPolicy']['MaximumRetryCount'], 3)
+
     def test_rm(self):
         service = self.project.get_service('simple')
         service.create_container()

tests/integration/service_test.py

@@ -389,3 +389,25 @@ def test_resolve_env(self):
             del os.environ['FILE_DEF']
             del os.environ['FILE_DEF_EMPTY']
             del os.environ['ENV_DEF']
+
+    def test_restart_policy_default(self):
+        service = self.create_service('container')
+        container = service.start_container().inspect()
+        self.assertEqual(container['HostConfig']['RestartPolicy']['Name'], '')
+
+    def test_restart_policy_always(self):
+        service = self.create_service('container')
+        container = service.start_container(restart_policy='always').inspect()
+        self.assertEqual(container['HostConfig']['RestartPolicy']['Name'], 'always')
+
+    def test_restart_policy_on_failure(self):
+        service = self.create_service('container')
+        container = service.start_container(restart_policy='on-failure').inspect()
+        self.assertEqual(container['HostConfig']['RestartPolicy']['Name'], 'on-failure')
+        self.assertEqual(container['HostConfig']['RestartPolicy']['MaximumRetryCount'], 0)
+
+    def test_restart_policy_on_failure_retry_count(self):
+        service = self.create_service('container')
+        container = service.start_container(restart_policy='on-failure:3').inspect()
+        self.assertEqual(container['HostConfig']['RestartPolicy']['Name'], 'on-failure')
+        self.assertEqual(container['HostConfig']['RestartPolicy']['MaximumRetryCount'], 3)

tests/unit/service_test.py

@@ -17,6 +17,7 @@
     parse_volume_spec,
     build_volume_binding,
     APIError,
+    parse_restart_policy,
 )
 
 
@@ -205,6 +206,18 @@ def test_create_container_from_insecure_registry(self, mock_log):
         self.mock_client.pull.assert_called_once_with('someimage:sometag', insecure_registry=True, stream=True)
         mock_log.info.assert_called_once_with('Pulling image someimage:sometag...')
 
+    def test_parse_restart_policy(self):
+        test_args = {
+            None: None,
+            '': None,
+            'no': None,
+            'always': {'Name':'always'},
+            'on-failure': {'Name':'on-failure'},
+            'on-failure:3': {'Name':'on-failure', 'MaximumRetryCount':3},
+        }
+        for k, v in test_args.items():
+            self.assertEqual(parse_restart_policy(k), v)
+
 
 class ServiceVolumesTest(unittest.TestCase):