4.2 KiB
Configurable introspection data storage backend
https://storyboard.openstack.org/#!/story/1726713
This spec proposes a mechanism to read and write introspection data from configured storage backend, and additionally provides support to read and write introspection data in ironic inspector database.
Problem description
Currently, introspection data can only be stored in Swift, there are no alternatives in an environment where Swift is not adopted. Also there is lack of mechanisms to support other storage backends by extending ironic-inspector with extensions.
Proposed change
Adds a table named
introspection_data
to store introspection data.Adds an inspector plugin named
introspection_data
which supports three types of storage backend:none
,swift
, anddatabase
.Each type of storage backend exposes two interfaces:
def get(self, node_id, suffix=None): pass def save(self, node_info, data, suffix=None): pass
Adds a plugin manager to dynamically load driver extensions according to the configuration option
[processing]storage_backend
, in a way similar to rule manager.Adds a new entry point to the setup.cfg:
ironic_inspector.introspection.storage_backend = none = ironic_inspector.plugins.introspection_data:NoStore swift = ironic_inspector.plugins.introspection_data:SwiftStore database = ironic_inspector.plugins.introspection_data:DatabaseStore
Alternatives
None
Data model impact
A new table named introspection_data
will be created,
with three fields:
uuid
: String(36), foreign key tonode.uuid
.processed
: Boolean, used to determine whether the introspection data is processed or not. Currently, inspector uses suffixUNPROCESSED
for unprocessed data,None
for processed data, This will be mapped to the boolean field.Note
The Swift storage backend uses suffix as part of the object name:
inspector_data-<uuid>[-suffix]
.data
: JsonEncodedDict(), LONGTEXT for MySQL. This field is used as the storage of introspected data.
When a node is removed from the cache, the associated introspection data will be removed as well.
HTTP API impact
None
Client (CLI) impact
None
Ironic python agent impact
None
Performance and scalability impact
None
Security impact
None
Deployer impact
Configuration option [processing]storage_backend
will
have database
as a valid value. When set, the inspected
data will be stored to ironic inspector database.
Swift is not a mandatory requirement for storing introspection data in this case.
Developer impact
After this feature is implemented, additional plugins can be implemented to support other type of stores.
Upgrades and Backwards Compatibility
Database upgrade will be handled by ironic-inspector-dbsync.
Provides a tool to assist with the migration of existing introspection data between Swift and database, e.g.:
$ ironic-inspector-migrate-data --from swift --to database
$ ironic-inspector-migrate-data --from database --to swift
Implementation
Assignee(s)
- Primary assignee:
-
kaifeng
Work Items
- Implements db layer support.
- Implements inspection data plugin, migrates swift support into plugin as a storage backend.
- Implements database storage backend.
- Creates introspection data plugin manager to load driver instance according to configuration option, rework introspection data read/write access based on interfaces provided by introspection data plugin.
- Implements the tool to help with introspection data migration.
Dependencies
None
Testing
This will be covered by unit tests and functional tests.
References
None