From e77322c17931810f4029ef339a791f702f2f4580 Mon Sep 17 00:00:00 2001
From: Mike Fedosin <mfedosin@mirantis.com>
Date: Wed, 1 Jun 2016 21:02:29 +0300
Subject: [PATCH] Don't update tags every time

This code removes unnecessary PATCH requests
for tags updating if they were not modified.

Change-Id: I8eced32f39d0c98e0b26014e7b2341ab6580ff01
Closes-bug: 1587999
---
 glanceclient/tests/unit/v2/test_images.py | 31 +++++++++++++++++++++++
 glanceclient/v2/schemas.py                |  9 +++----
 2 files changed, 34 insertions(+), 6 deletions(-)

diff --git a/glanceclient/tests/unit/v2/test_images.py b/glanceclient/tests/unit/v2/test_images.py
index 73bb074c..c7baf943 100644
--- a/glanceclient/tests/unit/v2/test_images.py
+++ b/glanceclient/tests/unit/v2/test_images.py
@@ -381,6 +381,20 @@ data_fixtures = {
             '',
         )
     },
+    '/v2/images/a2b83adc-888e-11e3-8872-78acc0b951d9': {
+        'GET': (
+            {},
+            {
+                'id': 'a2b83adc-888e-11e3-8872-78acc0b951d9',
+                'name': 'image-1',
+                'tags': ['tag1', 'tag2'],
+            },
+        ),
+        'PATCH': (
+            {},
+            '',
+        )
+    },
     '/v2/images?limit=%d&os_distro=NixOS' % images.DEFAULT_PAGE_SIZE: {
         'GET': (
             {},
@@ -982,6 +996,23 @@ class TestController(testtools.TestCase):
         # will not actually change - yet in real life it will...
         self.assertEqual('image-3', image.name)
 
+    def test_update_add_prop_with_tags(self):
+        image_id = 'a2b83adc-888e-11e3-8872-78acc0b951d9'
+        params = {'finn': 'human'}
+        image = self.controller.update(image_id, **params)
+        expect_hdrs = {
+            'Content-Type': 'application/openstack-images-v2.1-json-patch',
+        }
+        expect_body = [[('op', 'add'), ('path', '/finn'), ('value', 'human')]]
+        expect = [
+            ('GET', '/v2/images/%s' % image_id, {}, None),
+            ('PATCH', '/v2/images/%s' % image_id, expect_hdrs, expect_body),
+            ('GET', '/v2/images/%s' % image_id, {}, None),
+        ]
+        self.assertEqual(expect, self.api.calls)
+        self.assertEqual(image_id, image.id)
+        self.assertEqual('image-1', image.name)
+
     def test_update_bad_additionalProperty_type(self):
         image_id = 'e7e59ff6-fa2e-4075-87d3-1a1398a07dc3'
         params = {'name': 'pong', 'bad_prop': False}
diff --git a/glanceclient/v2/schemas.py b/glanceclient/v2/schemas.py
index 8247d313..8c838f8c 100644
--- a/glanceclient/v2/schemas.py
+++ b/glanceclient/v2/schemas.py
@@ -31,12 +31,12 @@ class SchemaBasedModel(warlock.Model):
     """
 
     def _make_custom_patch(self, new, original):
-        if not self.get('tags'):
-            tags_patch = []
-        else:
+        if 'tags' in new and 'tags' not in original:
             tags_patch = [{"path": "/tags",
                            "value": self.get('tags'),
                            "op": "replace"}]
+        else:
+            tags_patch = []
 
         patch_string = jsonpatch.make_patch(original, new).to_string()
         patch = json.loads(patch_string)
@@ -55,9 +55,6 @@ class SchemaBasedModel(warlock.Model):
                 if (name not in original and name in new and
                         prop.get('is_base', True)):
                     original[name] = None
-
-        original['tags'] = None
-        new['tags'] = None
         return self._make_custom_patch(new, original)