discourse/app/serializers/theme_serializer.rb
Martin Brennan 19af83d39e
FEATURE: Themeable site settings (#32233)
This commit introduces the concept of themeable site settings,
which is a new tool for theme authors that lives alongside theme
modifiers and theme settings. Here is a quick summary:

* Theme settings - These are custom settings used to control UI and functionality within your theme or component and provide configuration options. These cannot change core Discourse functionality.
* Theme modifiers - Allows a theme or a component to modify selected server-side functionality of core Discourse as an alternative to building a plugin.
* Themeable site settings (new) - Allows a theme (not components) to override a small subset of core site settings, which generally control parts of the UI and other minor functionality. This allows themes to have a greater control over the full site experience.

Themeable site settings will be shown for all themes, whether the theme
changes
the value or not, and have a similar UI to custom theme settings.

We are also introducing a new page at
`/admin/config/theme-site-settings` that
allows admins to see all possible themeable site settings, and which
themes
are changing the value from the default.

### Configuration

Theme authors can configure initial values themeable site settings using
a section in the `about.json` file like so:

```json
"theme_site_settings": {
  "search_experience": "search_field"
}
```

These values will not change when the theme updates, because we cannot
know if admins have manually changed them.

### Limitations

Themeable site settings are only really intended to control elements of
the UI, and when retrieving their value we require a theme ID, so these
limitations apply:

- Themeable site settings cannot be used in Sidekiq jobs
- Themeable site settings cannot be used in markdown rules
- Themeable site settings will be cached separately to client site
settings using theme ID as a key
- Themeable site settings will override keys on the `siteSettings`
service on the client using the application preloader
- `SiteSetting.client_settings_json` will not include themeable site
settings, instead you can call `SiteSetting.theme_site_settings_json`
with a theme ID

### Initial settings

There are only two site settings that will be themeable to begin with:

* `enable_welcome_banner`
* `search_experience`

And our new Horizon theme will take advantage of both. Over time, more
settings that control elements of the UI will be exposed this way.
2025-07-16 11:00:21 +10:00

111 lines
2.9 KiB
Ruby
Vendored

# frozen_string_literal: true
require "base64"
class ThemeSerializer < BasicThemeSerializer
attributes :color_scheme_id,
:user_selectable,
:auto_update,
:remote_theme_id,
:settings,
:themeable_site_settings,
:errors,
:supported?,
:enabled?,
:disabled_at,
:theme_fields,
:screenshot_url,
:system
has_one :color_scheme, serializer: ColorSchemeSerializer, embed: :object
has_one :owned_color_palette, serializer: ColorSchemeSerializer, embed: :object
has_one :base_palette, serializer: ColorSchemeSerializer, embed: :object
has_one :user, serializer: UserNameSerializer, embed: :object
has_one :disabled_by, serializer: UserNameSerializer, embed: :object
has_many :child_themes, serializer: BasicThemeSerializer, embed: :objects
has_many :parent_themes, serializer: BasicThemeSerializer, embed: :objects
has_one :remote_theme, serializer: RemoteThemeSerializer, embed: :objects
has_many :translations, serializer: ThemeTranslationSerializer, embed: :objects
def initialize(theme, options = {})
super
@include_theme_field_values = options[:include_theme_field_values] || false
@errors = []
object.theme_fields.each { |o| @errors << o.error if o.error }
end
def theme_fields
ActiveModel::ArraySerializer.new(
object.theme_fields,
each_serializer: ThemeFieldSerializer,
include_value: include_theme_field_values?,
).as_json
end
def include_theme_field_values?
# This is passed into each `ThemeFieldSerializer` to determine if `value` will be serialized.
# We only want to serialize if we are viewing staff_action_logs (for diffing changes), or if
# the theme is a local theme, so the saved values appear in the theme field editor.
@include_theme_field_values || object.remote_theme_id.nil?
end
def child_themes
object.child_themes
end
def parent_themes
object.parent_themes
end
def base_palette
ColorScheme.base
end
def include_base_palette?
object.color_scheme_id.blank? && object.owned_color_palette.blank?
end
def settings
object.settings.map do |_name, setting|
ThemeSettingsSerializer.new(setting, scope:, root: false)
end
rescue ThemeSettingsParser::InvalidYaml => e
@errors << e.message
nil
end
# Components always return an empty array here
def themeable_site_settings
object.themeable_site_settings
end
def include_themeable_site_settings?
!object.component?
end
def include_child_themes?
!object.component?
end
def errors
@errors
end
def include_errors?
@errors.present?
end
def include_disabled_at?
object.component? && !object.enabled?
end
def include_disabled_by?
include_disabled_at?
end
def system
object.system?
end
end