Add pagination and changes-since filter support for os-migrations API¶
https://blueprints.launchpad.net/nova/+spec/ add-pagination-and-change-since-for-migration-list
This blueprint add limit and marker optional parameters to GET /os-migrations request to support pagination.
This blueprint also add changes-since optional parameters to GET /os-migrations request to support filtering response data by updated time.
Problem description¶
Currently, os-migrations API does not support pagination. As in large scale deployment the number of migration records can be also very large query them all can lead to performance bottleneck, it will be very useful to support pagination.
Also, os-migrations API does not support filter the migration record by last updated time. As for production deployment, the system will be up for a very long time, and the number of migration records will also be very big. It will be very useful to support filter by last update time.
Use Cases¶
For large scale production deployment, the administrator can use pagination and lastest updated time filter to have more efficient database query.
Proposed change¶
Add an API microversion that allows to get several migrations using general pagination mechanism with the help of limit and marker`optional parameters to GET /os-migrations request. And add filter with the help of `changes-since optional parameter to GET /os-migrations request.
marker: The last migration ID of the previous page. Displays list of migrations after “marker”.
limit: Maximum number of migrations to display. If limit == -1, all migrations will be displayed. If limit is bigger than osapi_max_limit option of Nova API, limit osapi_max_limit will be used instead.
Alternatives¶
None
Data model impact¶
None
REST API impact¶
The proposal would add API microversion for getting several migrations using general pagination mechanism. New optional parameters limit, marker, and changes-since will be added to GET /os-migrations request.
Generic request format
GET /os-migrations?limit={limit}&marker={migration_id}
Get all migrations
GET /os-migrations
Response
{ "migrations": [ { "created_at": "2012-10-29T13:42:02.000000", "dest_compute": "compute2", "dest_host": "1.2.3.4", "dest_node": "node2", "id": 1234, "instance_uuid": "instance_id_123", "new_instance_type_id": 2, "old_instance_type_id": 1, "source_compute": "compute1", "source_node": "node1", "status": "Done", "updated_at": "2012-10-29T13:42:02.000000" }, { "created_at": "2013-10-22T13:42:02.000000", "dest_compute": "compute20", "dest_host": "5.6.7.8", "dest_node": "node20", "id": 5678, "instance_uuid": "instance_id_456", "new_instance_type_id": 6, "old_instance_type_id": 5, "source_compute": "compute10", "source_node": "node10", "status": "Done", "updated_at": "2013-10-22T13:42:02.000000" }, { "created_at": "2013-10-22T13:45:02.000000", "dest_compute": "compute21", "dest_host": "5.6.7.8", "dest_node": "node21", "id": 5679, "instance_uuid": "instance_id_4561", "new_instance_type_id": 6, "old_instance_type_id": 5, "source_compute": "compute10", "source_node": "node10", "status": "Done", "updated_at": "2013-10-22T13:45:02.000000" } ] }
Get no more than 2 migrations
GET /os-migrations?limit=2
Response
{ "migrations": [ { "created_at": "2012-10-29T13:42:02.000000", "dest_compute": "compute2", "dest_host": "1.2.3.4", "dest_node": "node2", "id": 1234, "instance_uuid": "instance_id_123", "new_instance_type_id": 2, "old_instance_type_id": 1, "source_compute": "compute1", "source_node": "node1", "status": "Done", "updated_at": "2012-10-29T13:42:02.000000" }, { "created_at": "2013-10-22T13:42:02.000000", "dest_compute": "compute20", "dest_host": "5.6.7.8", "dest_node": "node20", "id": 5678, "instance_uuid": "instance_id_456", "new_instance_type_id": 6, "old_instance_type_id": 5, "source_compute": "compute10", "source_node": "node10", "status": "Done", "updated_at": "2013-10-22T13:42:02.000000" } ] }
Get all migrations after id=1234
GET /os-migrations?marker=1234
Response
{ "migrations": [ { "created_at": "2013-10-22T13:42:02.000000", "dest_compute": "compute20", "dest_host": "5.6.7.8", "dest_node": "node20", "id": 5678, "instance_uuid": "instance_id_456", "new_instance_type_id": 6, "old_instance_type_id": 5, "source_compute": "compute10", "source_node": "node10", "status": "Done", "updated_at": "2013-10-22T13:42:02.000000" }, { "created_at": "2013-10-22T13:45:02.000000", "dest_compute": "compute21", "dest_host": "5.6.7.8", "dest_node": "node21", "id": 5679, "instance_uuid": "instance_id_4561", "new_instance_type_id": 6, "old_instance_type_id": 5, "source_compute": "compute10", "source_node": "node10", "status": "Done", "updated_at": "2013-10-22T13:45:02.000000" } ] }
Request format
GET /os-migrations?changes-since=2013-10-22T13:45:02.000000
Response
{
"migrations":[
{
"created_at": "2013-10-22T13:45:02.000000",
"dest_compute": "compute21",
"dest_host": "5.6.7.8",
"dest_node": "node21",
"id": 1234,
"instance_uuid": "instance_id_4561",
"new_instance_type_id": 6,
"old_instance_type_id": 5,
"source_compute": "compute10",
"source_node": "node10",
"status": "Done",
"updated_at": "2013-10-22T13:45:02.000000"
}
]
}
Security impact¶
None
Notifications impact¶
None
Other end user impact¶
None
Performance Impact¶
Reduce load on Horizon with the help of pagination and time filtering of retrieving migrations from Nova side.
Other deployer impact¶
None
Developer impact¶
None
Implementation¶
Assignee(s)¶
- Primary assignee:
Zheng Zhenyu
Work Items¶
Create a new API microversion for getting several migrations using general pagination mechanism and time stamp filtering.
Dependencies¶
None
Testing¶
Would need new Tempest, functional and unit tests.
Documentation Impact¶
Docs needed for new API microversion and usage.
