Fix create_region_with_id raise 500 Error bug

1. add sql.handle_conflicts wrapper in sql backend driver.
2. check duplicate region id in kvs backend driver.
3. add 2 test cases to check exception.Conflict when create duplicate id region.

Closes-Bug: #1283904

Change-Id: Icfc5edf661501a5c134f324a76824812dbda2760

keystone/catalog/backends/sql.py

@@ -134,6 +134,7 @@ class Catalog(catalog.Driver):
             session.query(Region).filter_by(id=region_id).delete()
             session.delete(ref)
 
+    @sql.handle_conflicts(conflict_type='region')
     def create_region(self, region_ref):
         session = sql.get_session()
         with session.begin():

keystone/catalog/core.py

@@ -69,6 +69,15 @@ class Manager(manager.Manager):
         super(Manager, self).__init__(CONF.catalog.driver)
 
     def create_region(self, region_ref):
+        # Check duplicate ID
+        try:
+            self.get_region(region_ref['id'])
+        except exception.RegionNotFound:
+            pass
+        else:
+            msg = _('Duplicate ID, %s.') % region_ref['id']
+            raise exception.Conflict(type='region', details=msg)
+
         try:
             return self.driver.create_region(region_ref)
         except exception.NotFound:

keystone/tests/test_backend.py

@@ -3553,6 +3553,18 @@ class CatalogTests(object):
                           self.catalog_api.get_region,
                           region_id)
 
+    def test_create_region_with_duplicate_id(self):
+        region_id = uuid.uuid4().hex
+        new_region = {
+            'id': region_id,
+            'description': uuid.uuid4().hex
+        }
+        self.catalog_api.create_region(new_region)
+        # Create region again with duplicate id
+        self.assertRaises(exception.Conflict,
+                          self.catalog_api.create_region,
+                          new_region)
+
     def test_get_region_404(self):
         self.assertRaises(exception.RegionNotFound,
                           self.catalog_api.get_region,

keystone/tests/test_v3_catalog.py

@@ -49,6 +49,17 @@ class CatalogTestCase(test_v3.RestfulTestCase):
         # populated with a UUID, as is the case with POST /v3/regions
         self.assertEqual(region_id, r.json['region']['id'])
 
+    def test_create_region_with_duplicate_id(self):
+        """Call ``PUT /regions/{region_id}``."""
+        ref = dict(description="my region")
+        self.put(
+            '/regions/myregion',
+            body={'region': ref}, expected_status=201)
+        # Create region again with duplicate id
+        self.put(
+            '/regions/myregion',
+            body={'region': ref}, expected_status=409)
+
     def test_create_region(self):
         """Call ``POST /regions`` with an ID in the request body."""
         # the ref will have an ID defined on it
@@ -275,7 +286,7 @@ class CatalogTestCase(test_v3.RestfulTestCase):
             expected_status=400)
 
     def assertValidErrorResponse(self, response):
-        self.assertIn(response.status_code, [400])
+        self.assertIn(response.status_code, [400, 409])
 
     def test_create_endpoint_400(self):
         """Call ``POST /endpoints``."""