Defaulted amazon disk & container formats

Fixes bug 972014

Default unset disk/container format to the corresponding container/disk
format, where the latter is an amazon format requiring a strict match.

Change-Id: I147df146940a21c368e95901343f36e1e3b7495b

glance/registry/db/api.py

@@ -463,6 +463,30 @@ def validate_image(values):
         msg = "Invalid image status '%s' for image." % status
         raise exception.Invalid(msg)
 
+    def _amazon_format(disk, container):
+        amazon_formats = ('aki', 'ari', 'ami')
+        return ((disk in amazon_formats and
+                 (container in CONTAINER_FORMATS or container is None)) or
+                (container in amazon_formats and
+                 (disk in DISK_FORMATS or disk is None)))
+
+    def _only_one_of(a, b):
+        return (a and b is None) or (b and a is None)
+
+    if _amazon_format(disk_format, container_format):
+        if _only_one_of(container_format, disk_format):
+            container_format = (container_format if disk_format is None
+                                else disk_format)
+            values['container_format'] = container_format
+            disk_format = container_format
+            values['disk_format'] = disk_format
+        elif container_format != disk_format:
+            msg = ("Invalid mix of disk and container formats. "
+                   "When setting a disk or container format to "
+                   "one of 'aki', 'ari', or 'ami', the container "
+                   "and disk formats must match.")
+            raise exception.Invalid(msg)
+
     def _required_format_absent(format, formats):
         activating = status == 'active'
         unrecognized = format not in formats
@@ -481,20 +505,19 @@ def _required_format_absent(format, formats):
         msg = "Invalid container format '%s' for image." % container_format
         raise exception.Invalid(msg)
 
-    if disk_format in ('aki', 'ari', 'ami') or\
-            container_format in ('aki', 'ari', 'ami'):
-        if container_format != disk_format:
-            msg = ("Invalid mix of disk and container formats. "
-                   "When setting a disk or container format to "
-                   "one of 'ami', 'ari', or 'ami', the container "
-                   "and disk formats must match.")
-            raise exception.Invalid(msg)
-
     name = values.get('name')
     if name and len(name) > 255:
         msg = _('Image name too long: %d') % len(name)
         raise exception.Invalid(msg)
 
+    return values
+
+
+def _update_values(image_ref, values):
+    for k in values.keys():
+        if getattr(image_ref, k) != values[k]:
+            setattr(image_ref, k, values[k])
+
 
 def _image_update(context, values, image_id, purge_props=False):
     """
@@ -547,7 +570,8 @@ def _image_update(context, values, image_id, purge_props=False):
         # investigation, the @validates decorator does not validate
         # on new records, only on existing records, which is, well,
         # idiotic.
-        validate_image(image_ref.to_dict())
+        values = validate_image(image_ref.to_dict())
+        _update_values(image_ref, values)
 
         try:
             image_ref.save(session=session)

glance/tests/unit/v1/test_api.py

@@ -2012,6 +2012,28 @@ def destroy_fixtures(self):
         db_models.unregister_models(db_api._ENGINE)
         db_models.register_models(db_api._ENGINE)
 
+    def _do_test_defaulted_format(self, format_key, format_value):
+        fixture_headers = {'x-image-meta-name': 'defaulted',
+                           'x-image-meta-location': 'http://foo.com/image',
+                           format_key: format_value}
+
+        req = webob.Request.blank("/images")
+        req.method = 'POST'
+        for k, v in fixture_headers.iteritems():
+            req.headers[k] = v
+
+        res = req.get_response(self.api)
+        self.assertEquals(res.status_int, 201)
+        res_body = json.loads(res.body)['image']
+        self.assertEquals(format_value, res_body['disk_format'])
+        self.assertEquals(format_value, res_body['container_format'])
+
+    def test_defaulted_amazon_format(self):
+        for key in ('x-image-meta-disk-format',
+                    'x-image-meta-container-format'):
+            for value in ('aki', 'ari', 'ami'):
+                self._do_test_defaulted_format(key, value)
+
     def test_bad_disk_format(self):
         fixture_headers = {'x-image-meta-store': 'bad',
                    'x-image-meta-name': 'bogus',