Comment 0 for bug 1777892

Unified limits consists of registered limits and limits, which are project-specific. Both types are isolated into separate database tables (keystone.registered_limit and keystone.limit).

Currently, the schema for keystone.registered_limit is:

mysql> describe keystone.registered_limit;
+---------------+--------------+------+-----+---------+-------+
| Field | Type | Null | Key | Default | Extra |
+---------------+--------------+------+-----+---------+-------+
| id | varchar(64) | NO | PRI | NULL | |
| service_id | varchar(255) | YES | MUL | NULL | |
| region_id | varchar(64) | YES | MUL | NULL | |
| resource_name | varchar(255) | YES | | NULL | |
| default_limit | int(11) | NO | | NULL | |
| description | text | YES | | NULL | |
+---------------+--------------+------+-----+---------+-------+
6 rows in set (0.00 sec)

The following is the schema for keystone.limit:

mysql> describe keystone.limit;
+----------------+--------------+------+-----+---------+-------+
| Field | Type | Null | Key | Default | Extra |
+----------------+--------------+------+-----+---------+-------+
| id | varchar(64) | NO | PRI | NULL | |
| project_id | varchar(64) | YES | MUL | NULL | |
| service_id | varchar(255) | YES | MUL | NULL | |
| region_id | varchar(64) | YES | | NULL | |
| resource_name | varchar(255) | YES | | NULL | |
| resource_limit | int(11) | NO | | NULL | |
| description | text | YES | | NULL | |
+----------------+--------------+------+-----+---------+-------+
7 rows in set (0.00 sec)

There are some duplicated attributes between these two tables that are requirements for the API (e.g. a limit cannot be created without a corresponding limit being registered first). We have the opportunity to simplify the schema of the keystone.limit table by removing limit.service_id, limit.region_id, and limit.resource_name in favor of a single column called limit.registered_limit_id that maintains a FK relationship to a record in keystone.registered_limit.

The unified limit API will use the FK relationship to populate service_id, region_id, and resource_name attributes of a limit from the corresponding registered_limit.