[meta] uiSettings service improvements

[mshustov]

Umbrella ticket to track possible improvements

• Revisions *
  (Updated on 1 June 2021: Grouped into categories)
  (3 Feb 2022: added injected_metadata_service comment)
  (22 Feb 2022: added telemetry from all spaces)

Consistency

• unify naming/use consistent terms (unify naming. currently used as config, settings, ui settings, advanced settings #126991)
• consistent server & client type interface for the uiSettings client (Per-user profiles, settings in Kibana #17888)
• type naming should start with UiSettings prefix Add UiSettings validation & Kibana default route redirection #59694 (comment)

Dynamic settings

• update settings / permission management [uiSettings] allow update of settings and/or permission management for uiSettings #94668

Setting(s) ownership/permissions

• settings are rendered in UI and can be modified even if a plugin-owner is disabled [Advanced Settings] hide unknown uiSettings from the UI #94876 (bug)
• plugins may have access to their own uiSettings only Plugins should only be able to directly access UiSettings that they registered #101907
• plugins should be aware of UiSettings value change Plugins should be aware of UiSettings values change #83084
• audit settings:
  • what settings are shared between apps (related to Per-user profiles, settings in Kibana #17888)
  • what settings (if any) are configured and used by plugins that don't have a 1 to 1 mapping with uiSettings (related to standardizing the way we register and use uiSettings within the platform)

Setting(s) validation

• value validator Support validation for UI Settings #46717
• throw on unknown overrides uiSettings should throw an error on unknown overrides #101295

API changes

• Consider removing the injected_metadata_service (NP migration and support for 3rd party plugins)
• get rid of defaults term as non-descriptive UI settings move to NP #47590 (comment)
• add category related fields [uiSettings] allow to enhance categories / add category related fields #95627
• support 'global' and 'space-aware' settings (needed for user profile service & telemetry)
• explore the need for uiSettings migrations (make registering uiSettings migrations more developer-friendly #123257)
• support ui settings deprecations ([uiSettings] Support deprecations API #103010)

Telemetry to optimize defaults

• Convert stack_management to report UI Settings from all Spaces

Done

• remove client-side validation support Remove UiSettings client side validation #83038 (validation)
• boost performance of getAll() (related to [Core] uiSettingsClient.getRaw function is slow because of its use of _.defaultDeep #97025), or remove getAll()

[elasticmachine]

Pinging @elastic/kibana-platform (Team:Platform)

[mattkime]

This issue contains discussion related to uiSettings, particularly sync/async interfaces - #53268

tldr; it would be nice to have a common interface. Also, sometimes we need a sync interface for things like field formatters that can't be async. Might be nice to have an api that provides a cached set of values.

[mshustov]

the problem with UI settings seems to be quite similar to SavedObjects:

• settings adjusted outside of the context of a plugin-owner.
  • a plugin cannot add custom logic on value change. see [Advanced Settings] Introducing telemetry #82860 (comment)
  • AdvancedSettings UI does not exist in the plugin context and a user has to navigate to the Management screen. Need to discuss with PM whether we want to address it eventually @alexfrancoeur
• it's hard to share business rules for UI & server. For example, we enforced server-side validation, but there are still several legacy validation rules on the client (ImageValidation | StringValidation) that must be migrated to the server-side.