Move shared V1/V2 code into common methods and fix verbs

data/model/image.py

@@ -360,6 +360,27 @@ def get_repo_image_by_storage_checksum(namespace, repository_name, storage_check
     raise InvalidImageException(msg)
 
 
+def get_image_json(image, store):
+  """ Returns the JSON definition data for this image. """
+  if image.v1_json_metadata:
+    return image.v1_json_metadata
+
+  return store.get_content(image.storage.locations, store.image_json_path(image.storage.uuid))
+
+
+def get_image_ancestors(image, include_image=True):
+  """ Returns a query of the full ancestors of an image, including itself. """
+  ancestors = image.ancestors.split('/')[1:-1]
+  image_ids = [ancestor_id for ancestor_id in ancestors if ancestor_id]
+  if include_image:
+    image_ids.append(image.id)
+
+  if not image_ids:
+    return []
+
+  return Image.select().where(Image.id << image_ids)
+
+
 def synthesize_v1_image(namespace, repository_name, storage_checksum, docker_image_id,
                         created_date_str, comment, command, v1_json_metadata, parent_docker_id):
   """ Find an existing image with this docker image id, and if none exists, write one with the