Added devices configuration option

Signed-off-by: Dan Elbert <dan.elbert@gmail.com>

Author: delbert@umn.edu

compose/config.py

@@ -10,6 +10,7 @@
     'cpuset',
     'command',
     'detach',
+    'devices',
     'dns',
     'dns_search',
     'domainname',
@@ -50,6 +51,7 @@
     'add_host': 'extra_hosts',
     'hosts': 'extra_hosts',
     'extra_host': 'extra_hosts',
+    'device': 'devices',
     'link': 'links',
     'port': 'ports',
     'privilege': 'privileged',
@@ -200,11 +202,14 @@ def merge_service_dicts(base, override):
             override.get('environment'),
         )
 
-    if 'volumes' in base or 'volumes' in override:
-        d['volumes'] = merge_volumes(
-            base.get('volumes'),
-            override.get('volumes'),
-        )
+    path_mapping_keys = ['volumes', 'devices']
+
+    for key in path_mapping_keys:
+        if key in base or key in override:
+            d[key] = merge_path_mappings(
+                base.get(key),
+                override.get(key),
+            )
 
     if 'labels' in base or 'labels' in override:
         d['labels'] = merge_labels(
@@ -230,7 +235,7 @@ def merge_service_dicts(base, override):
         if key in base or key in override:
             d[key] = to_list(base.get(key)) + to_list(override.get(key))
 
-    already_merged_keys = ['environment', 'volumes', 'labels'] + list_keys + list_or_string_keys
+    already_merged_keys = ['environment', 'labels'] + path_mapping_keys + list_keys + list_or_string_keys
 
     for k in set(ALLOWED_KEYS) - set(already_merged_keys):
         if k in override:
@@ -346,7 +351,7 @@ def resolve_host_paths(volumes, working_dir=None):
 
 
 def resolve_host_path(volume, working_dir):
-    container_path, host_path = split_volume(volume)
+    container_path, host_path = split_path_mapping(volume)
     if host_path is not None:
         host_path = os.path.expanduser(host_path)
         host_path = os.path.expandvars(host_path)
@@ -368,32 +373,32 @@ def validate_paths(service_dict):
             raise ConfigurationError("build path %s either does not exist or is not accessible." % build_path)
 
 
-def merge_volumes(base, override):
-    d = dict_from_volumes(base)
-    d.update(dict_from_volumes(override))
-    return volumes_from_dict(d)
+def merge_path_mappings(base, override):
+    d = dict_from_path_mappings(base)
+    d.update(dict_from_path_mappings(override))
+    return path_mappings_from_dict(d)
 
 
-def dict_from_volumes(volumes):
-    if volumes:
-        return dict(split_volume(v) for v in volumes)
+def dict_from_path_mappings(path_mappings):
+    if path_mappings:
+        return dict(split_path_mapping(v) for v in path_mappings)
     else:
         return {}
 
 
-def volumes_from_dict(d):
-    return [join_volume(v) for v in d.items()]
+def path_mappings_from_dict(d):
+    return [join_path_mapping(v) for v in d.items()]
 
 
-def split_volume(string):
+def split_path_mapping(string):
     if ':' in string:
         (host, container) = string.split(':', 1)
         return (container, host)
     else:
         return (string, None)
 
 
-def join_volume(pair):
+def join_path_mapping(pair):
     (container, host) = pair
     if host is None:
         return container

compose/service.py

@@ -20,6 +20,7 @@
 DOCKER_START_KEYS = [
     'cap_add',
     'cap_drop',
+    'devices',
     'dns',
     'dns_search',
     'env_file',
@@ -441,13 +442,16 @@ def _get_container_host_config(self, override_options, one_off=False):
         extra_hosts = build_extra_hosts(options.get('extra_hosts', None))
         read_only = options.get('read_only', None)
 
+        devices = options.get('devices', None)
+
         return create_host_config(
             links=self._get_links(link_to_self=one_off),
             port_bindings=port_bindings,
             binds=volume_bindings,
             volumes_from=options.get('volumes_from'),
             privileged=privileged,
             network_mode=self._get_net(),
+            devices=devices,
             dns=dns,
             dns_search=dns_search,
             restart_policy=restart,

docs/extends.md

@@ -342,8 +342,8 @@ environment:
   - BAZ=local
 ```
 
-Finally, for `volumes`, Compose "merges" entries together with locally-defined
-bindings taking precedence:
+Finally, for `volumes` and `devices`, Compose "merges" entries together with
+locally-defined bindings taking precedence:
 
 ```yaml
 # original service
@@ -361,4 +361,4 @@ volumes:
   - /original-dir/foo:/foo
   - /local-dir/bar:/bar
   - /local-dir/baz/:baz
-```
+```

docs/yml.md

@@ -29,8 +29,8 @@ image: a4bc65fd
 
 ### build
 
-Path to a directory containing a Dockerfile. When the value supplied is a 
-relative path, it is interpreted as relative to the location of the yml file 
+Path to a directory containing a Dockerfile. When the value supplied is a
+relative path, it is interpreted as relative to the location of the yml file
 itself. This directory is also the build context that is sent to the Docker daemon.
 
 Compose will build and tag it with a generated name, and use that image thereafter.
@@ -342,6 +342,16 @@ dns_search:
   - dc2.example.com
 ```
 
+### devices
+
+List of device mappings.  Uses the same format as the `--device` docker 
+client create option.
+
+```
+devices:
+  - "/dev/ttyUSB0:/dev/ttyUSB0"
+```
+
 ### working\_dir, entrypoint, user, hostname, domainname, mem\_limit, privileged, restart, stdin\_open, tty, cpu\_shares, cpuset, read\_only
 
 Each of these is a single value, analogous to its

tests/integration/service_test.py

@@ -669,3 +669,16 @@ def test_log_drive_none(self):
 
         self.assertEqual('none', log_config['Type'])
         self.assertFalse(log_config['Config'])
+
+    def test_devices(self):
+        service = self.create_service('web', devices=["/dev/random:/dev/mapped-random"])
+        device_config = create_and_start_container(service).get('HostConfig.Devices')
+
+        device_dict = {
+            'PathOnHost': '/dev/random',
+            'CgroupPermissions': 'rwm',
+            'PathInContainer': '/dev/mapped-random'
+        }
+
+        self.assertEqual(1, len(device_config))
+        self.assertDictEqual(device_dict, device_config[0])

tests/unit/config_test.py

@@ -54,46 +54,61 @@ def test_volume_binding_with_home(self):
         self.assertEqual(d['volumes'], ['/home/user:/container/path'])
 
 
-class MergeVolumesTest(unittest.TestCase):
+class MergePathMappingTest(object):
+    def config_name(self):
+        return ""
+
     def test_empty(self):
         service_dict = config.merge_service_dicts({}, {})
-        self.assertNotIn('volumes', service_dict)
+        self.assertNotIn(self.config_name(), service_dict)
 
     def test_no_override(self):
         service_dict = config.merge_service_dicts(
-            {'volumes': ['/foo:/code', '/data']},
+            {self.config_name(): ['/foo:/code', '/data']},
             {},
         )
-        self.assertEqual(set(service_dict['volumes']), set(['/foo:/code', '/data']))
+        self.assertEqual(set(service_dict[self.config_name()]), set(['/foo:/code', '/data']))
 
     def test_no_base(self):
         service_dict = config.merge_service_dicts(
             {},
-            {'volumes': ['/bar:/code']},
+            {self.config_name(): ['/bar:/code']},
         )
-        self.assertEqual(set(service_dict['volumes']), set(['/bar:/code']))
+        self.assertEqual(set(service_dict[self.config_name()]), set(['/bar:/code']))
 
     def test_override_explicit_path(self):
         service_dict = config.merge_service_dicts(
-            {'volumes': ['/foo:/code', '/data']},
-            {'volumes': ['/bar:/code']},
+            {self.config_name(): ['/foo:/code', '/data']},
+            {self.config_name(): ['/bar:/code']},
         )
-        self.assertEqual(set(service_dict['volumes']), set(['/bar:/code', '/data']))
+        self.assertEqual(set(service_dict[self.config_name()]), set(['/bar:/code', '/data']))
 
     def test_add_explicit_path(self):
         service_dict = config.merge_service_dicts(
-            {'volumes': ['/foo:/code', '/data']},
-            {'volumes': ['/bar:/code', '/quux:/data']},
+            {self.config_name(): ['/foo:/code', '/data']},
+            {self.config_name(): ['/bar:/code', '/quux:/data']},
         )
-        self.assertEqual(set(service_dict['volumes']), set(['/bar:/code', '/quux:/data']))
+        self.assertEqual(set(service_dict[self.config_name()]), set(['/bar:/code', '/quux:/data']))
 
     def test_remove_explicit_path(self):
         service_dict = config.merge_service_dicts(
-            {'volumes': ['/foo:/code', '/quux:/data']},
-            {'volumes': ['/bar:/code', '/data']},
+            {self.config_name(): ['/foo:/code', '/quux:/data']},
+            {self.config_name(): ['/bar:/code', '/data']},
         )
-        self.assertEqual(set(service_dict['volumes']), set(['/bar:/code', '/data']))
+        self.assertEqual(set(service_dict[self.config_name()]), set(['/bar:/code', '/data']))
+
+
+class MergeVolumesTest(unittest.TestCase, MergePathMappingTest):
+    def config_name(self):
+        return 'volumes'
+
+
+class MergeDevicesTest(unittest.TestCase, MergePathMappingTest):
+    def config_name(self):
+        return 'devices'
+
 
+class BuildOrImageMergeTest(unittest.TestCase):
     def test_merge_build_or_image_no_override(self):
         self.assertEqual(
             config.merge_service_dicts({'build': '.'}, {}),