Add cache_from to build opts

Signed-off-by: Joey Payne <[email protected]>

compose/config/config_schema_v3.1.json

@@ -71,7 +71,8 @@
               "properties": {
                 "context": {"type": "string"},
                 "dockerfile": {"type": "string"},
-                "args": {"$ref": "#/definitions/list_or_dict"}
+                "args": {"$ref": "#/definitions/list_or_dict"},
+                "cache_from": {"type": "#/definitions/list_of_strings"}
               },
               "additionalProperties": false
             }

compose/service.py

@@ -802,6 +802,7 @@ class Service(object):
             nocache=no_cache,
             dockerfile=build_opts.get('dockerfile', None),
             buildargs=build_opts.get('args', None),
+            cache_from=build_opts.get('cache_from', None),
         )
 
         try: