Fix wrong UniqueConstraint name

Table `sourseassoc` has a conflicted with
OpenStack naming convention UniqueConstraint name.
Each UniqueConstraint should be named as
`uniq_table_name0column_first0column_second`.

bp: ceilometer-db-sync-models-with-migrations

Change-Id: Ic35a9351add9dd3ce014c938505e268e131112e8

ceilometer/storage/sqlalchemy/alembic/versions/2c3ccda5a3ad_fix_uniq_name.py

@@ -0,0 +1,71 @@
+# -*- encoding: utf-8 -*-
+#
+# Copyright 2010-2011 OpenStack Foundation
+# Copyright 2012-2013 IBM Corp. #
+#
+# Authors: Svetlana Shturm <sshturm@mirantis.com>
+#
+# Licensed under the Apache License, Version 2.0 (the "License"); you may
+# not use this file except in compliance with the License. You may obtain
+# a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+# WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+# License for the specific language governing permissions and limitations
+# under the License.
+"""Fix name of UniqueConstraint according to OpenStack naming convention
+
+Revision ID: 2c3ccda5a3ad
+Revises: b6ae66d05e3
+Create Date: 2013-08-19 18:06:03.409584
+
+"""
+
+# revision identifiers, used by Alembic.
+revision = '2c3ccda5a3ad'
+down_revision = 'b6ae66d05e3'
+
+from alembic import op
+
+
+TABLE_NAME = 'sourceassoc'
+OLD_NAME = 'uniq_sourceassoc0meter_id'
+NEW_NAME = 'uniq_sourceassoc0meter_id0user_id'
+COLUMNS = ('meter_id', 'user_id')
+
+
+def change_uniq(table_name, old_name, new_name, columns):
+    engine = op.get_bind().engine
+    if engine.name == 'sqlite':
+        return
+    if engine.name == 'mysql':
+        # For mysql dialect all dependent FK should be removed
+        #  before renaming of constraint.
+        op.drop_constraint('fk_sourceassoc_meter_id',
+                           table_name,
+                           type_='foreignkey')
+        op.drop_constraint('fk_sourceassoc_user_id',
+                           table_name,
+                           type_='foreignkey')
+    try:
+        # For some versions of dialects constraint can be skipped.
+        op.drop_constraint(old_name, table_name=table_name, type_='unique')
+    except Exception:
+        pass
+    op.create_unique_constraint(new_name, table_name, columns)
+    if engine.name == 'mysql':
+        op.create_foreign_key('fk_sourceassoc_meter_id', table_name, 'meter',
+                              ['meter_id'], ['id'])
+        op.create_foreign_key('fk_sourceassoc_user_id', table_name, 'user',
+                              ['user_id'], ['id'])
+
+
+def upgrade():
+    change_uniq(TABLE_NAME, OLD_NAME, NEW_NAME, COLUMNS)
+
+
+def downgrade():
+    change_uniq(TABLE_NAME, NEW_NAME, OLD_NAME, COLUMNS)

ceilometer/storage/sqlalchemy/models.py

@@ -23,7 +23,7 @@ import urlparse
 
 from oslo.config import cfg
 from sqlalchemy import Column, Integer, String, Table, ForeignKey, DateTime, \
-    Index
+    Index, UniqueConstraint
 from sqlalchemy import Float, Boolean, Text
 from sqlalchemy.ext.declarative import declarative_base
 from sqlalchemy.orm import backref
@@ -104,6 +104,8 @@ Index('idx_sp', sourceassoc.c['source_id'], sourceassoc.c['project_id']),
 Index('idx_sr', sourceassoc.c['source_id'], sourceassoc.c['resource_id']),
 Index('idx_sm', sourceassoc.c['source_id'], sourceassoc.c['meter_id']),
 Index('ix_sourceassoc_source_id', sourceassoc.c['source_id'])
+UniqueConstraint(sourceassoc.c['meter_id'], sourceassoc.c['user_id'],
+                 name='uniq_sourceassoc0meter_id0user_id')
 
 
 class Source(Base):