077_convert_to_utf8: Convert *all* FK tables early

The original migration only takes care of migrating the instances
table before all others.  It turns out, when using MySQL with InnoDB
by default, there are many other tables with FKs that need to be converted
early on as well (see bug description for schema diagram).

Fixes bug 931602

Update: Convert all tables in a predefined order from within the same
execution.

Update: Avoid hard-coding database, fixes bug 930863

Update: Fix pep8 spacing

Change-Id: Ideb619eecef2ad067bda5c26612f761674dee924

nova/db/sqlalchemy/migrate_repo/versions/077_convert_to_utf8.py

@@ -29,31 +29,32 @@ def upgrade(migrate_engine):
     # not supporting key columns larger than 1000.
 
     if migrate_engine.name == "mysql":
-        # The instances table has to be converted early on. Also, the
-        # foreign_key_checks has to be disabled inside of the execute command
-        # that converts the instances table.
-        migrate_engine.execute("SET foreign_key_checks = 0;"
-            "ALTER TABLE instances CONVERT TO CHARACTER SET utf8")
-        tables = ["agent_builds", "aggregate_hosts", "aggregate_metadata",
-            "aggregates", "auth_tokens", "block_device_mapping",
-            "bw_usage_cache", "certificates", "compute_nodes", "console_pools",
-            "consoles", "fixed_ips", "floating_ips", "instance_actions",
-            "instance_faults", "instance_info_caches", "instance_metadata",
-            "instance_type_extra_specs", "instance_types", "iscsi_targets",
-            "key_pairs", "migrate_version", "migrations", "networks",
-            "projects", "provider_fw_rules", "quotas", "s3_images",
-            "security_group_instance_association", "security_group_rules",
-            "security_groups", "services", "sm_backend_config", "sm_flavors",
-            "sm_volume", "snapshots", "snapshots", "user_project_association",
-            "user_project_role_association", "user_role_association", "users",
+        tables = [
+            # tables that are FK parents, must be converted early
+            "aggregates", "console_pools", "instance_types", "instances",
+            "projects", "security_groups", "sm_backend_config", "sm_flavors",
+            "snapshots", "user_project_association", "users", "volume_types",
+            "volumes",
+            # those that are children and others later
+            "agent_builds", "aggregate_hosts", "aggregate_metadata",
+            "auth_tokens", "block_device_mapping", "bw_usage_cache",
+            "certificates", "compute_nodes", "consoles", "fixed_ips",
+            "floating_ips", "instance_actions", "instance_faults",
+            "instance_info_caches", "instance_metadata",
+            "instance_type_extra_specs", "iscsi_targets", "key_pairs",
+            "migrate_version", "migrations", "networks", "provider_fw_rules",
+            "quotas", "s3_images", "security_group_instance_association",
+            "security_group_rules", "services", "sm_volume",
+            "user_project_role_association", "user_role_association",
             "virtual_interfaces", "virtual_storage_arrays", "volume_metadata",
-            "volumes", "volume_type_extra_specs", "volume_types", "zones"]
+            "volume_type_extra_specs", "zones"]
+        sql = "SET foreign_key_checks = 0;"
         for table in tables:
-            migrate_engine.execute(
-                "ALTER TABLE %s CONVERT TO CHARACTER SET utf8" % table)
-        migrate_engine.execute("SET foreign_key_checks = 1")
-        migrate_engine.execute(
-            "ALTER DATABASE nova DEFAULT CHARACTER SET utf8")
+            sql += "ALTER TABLE %s CONVERT TO CHARACTER SET utf8;" % table
+        sql += "SET foreign_key_checks = 1;"
+        sql += "ALTER DATABASE %s DEFAULT CHARACTER SET utf8;" \
+            % migrate_engine.url.database
+        migrate_engine.execute(sql)
 
 
 def downgrade(migrate_engine):