Check that region ID is not an empty string

It generates an ID when a POST request to /regions has an empty string as ID

Change-Id: I49afd1f8c2e09ed31329bd8d1d88ca7f29ef7be9
Closes-Bug: 1322639

keystone/catalog/controllers.py

@@ -162,7 +162,7 @@ def create_region_with_id(self, context, region_id, region):
     def create_region(self, context, region):
         ref = self._normalize_dict(region)
 
-        if 'id' not in ref:
+        if not ref.get('id'):
             ref = self._assign_unique_id(ref)
 
         ref = self.catalog_api.create_region(ref)

keystone/tests/test_v3_catalog.py

@@ -78,6 +78,17 @@ def test_create_region(self):
                 'region_id': ref['id']})
         self.assertValidRegionResponse(r, ref)
 
+    def test_create_region_with_empty_id(self):
+        """Call ``POST /regions`` with an empty ID in the request body."""
+        ref = self.new_region_ref()
+        ref['id'] = ''
+
+        r = self.post(
+            '/regions',
+            body={'region': ref}, expected_status=201)
+        self.assertValidRegionResponse(r, ref)
+        self.assertNotEmpty(r.result['region'].get('id'))
+
     def test_create_region_without_id(self):
         """Call ``POST /regions`` without an ID in the request body."""
         ref = self.new_region_ref()