Supported group_add

Signed-off-by: George Lester <glester491@gmail.com>

compose/config/config.py

@@ -61,6 +61,7 @@ DOCKER_CONFIG_KEYS = [
     'env_file',
     'environment',
     'extra_hosts',
+    'group_add',
     'hostname',
     'image',
     'ipc',

compose/config/config_schema_v2.0.json

@@ -168,6 +168,13 @@
           ]
         },
         "oom_score_adj": {"type": "integer", "minimum": -1000, "maximum": 1000},
+        "group_add": {
+            "type": "array",
+            "items": {
+                "type": ["string", "number"]
+            },
+            "uniqueItems": true
+        },
         "pid": {"type": ["string", "null"]},
 
         "ports": {

compose/service.py

@@ -48,6 +48,7 @@ DOCKER_START_KEYS = [
     'dns_search',
     'env_file',
     'extra_hosts',
+    'group_add',
     'ipc',
     'read_only',
     'log_driver',
@@ -706,7 +707,8 @@ class Service(object):
             shm_size=options.get('shm_size'),
             tmpfs=options.get('tmpfs'),
             oom_score_adj=options.get('oom_score_adj'),
-            mem_swappiness=options.get('mem_swappiness')
+            mem_swappiness=options.get('mem_swappiness'),
+            group_add=options.get('group_add')
         )
 
     def build(self, no_cache=False, pull=False, force_rm=False):