2021-09-22 - Refactor theme inheritance
INFO
This document represents an architecture decision record (ADR) and has been mirrored from the ADR section in our Shopware 6 repository. You can find the original version here
Context
Currently the themes can only inherit config fields from the default Storefront theme. Also this inheritence is only a snapshot by activation time of the theme - The configs are copied to the new theme and changes to the default theme config will not appear in the new theme without a re-activation. The different possibilities to inherit different parts of a theme, like scripts, templates and config, can also cause problems on later updates.
Decision
To take this points into account we have decided to add a new inheritance key for the configFields in the theme.json which allow a theme to inherit its config from other themes in a given order:
"configInheritance": [
"@Storefront",
"@PreviousTheme",
"@MyDevelopmentTheme"
],Complete theme.json with part inheritances
{
"name": "MyDevelopmentTheme",
"author": "Shopware AG",
"views": [
"@Storefront",
"@Plugins",
"@MyDevelopmentTheme"
],
"style": [
"app/storefront/src/scss/overrides.scss",
"@Storefront",
"app/storefront/src/scss/base.scss"
],
"script": [
"@Storefront",
"app/storefront/dist/storefront/js/my-development-theme.js"
],
"asset": [
"@Storefront",
"app/storefront/src/assets"
],
"configInheritance": [
"@Storefront",
"@PreviousTheme",
"@MyDevelopmentTheme"
],
"config": {
"blocks": {
"exampleBlock": {
"label": {
"en-GB": "Example block",
"de-DE": "Beispiel Block"
}
}
},
"sections": {
"exampleSection": {
"label": {
"en-GB": "Example section",
"de-DE": "Beispiel Sektion"
}
}
},
"fields": {
"my-single-test-select-field": {
"editable": false
},
"my-single-select-field": {
"label": {
"en-GB": "Select a font size",
"de-DE": "Wähle ein Schriftgröße"
},
"type": "text",
"value": "24",
"custom": {
"componentName": "sw-single-select",
"options": [
{
"value": "16",
"label": {
"en-GB": "16px",
"de-DE": "16px"
}
},
{
"value": "20",
"label": {
"en-GB": "20px",
"de-DE": "20px"
}
},
{
"value": "24",
"label": {
"en-GB": "24px",
"de-DE": "24px"
}
}
]
},
"editable": true,
"block": "exampleBlock",
"section": "exampleSection"
},
"usps-positions": {
"label":
{
"en-GB": "Position",
"de-DE": "Position"
},
"scss": true,
"type": "text",
"value": [
"top",
"bottom"
],
"custom": {
"componentName": "sw-multi-select",
"options": [
{
"value": "bottom",
"label":
{
"en-GB": "bottom",
"de-DE": "unten"
}
},
{
"value": "top",
"label":
{
"en-GB": "top",
"de-DE": "oben"
}
},
{
"value": "middle",
"label":
{
"en-GB": "middle",
"de-DE": "mittel"
}
}
]
},
"editable": true,
"tab": "usps",
"block": "exampleBlock",
"section": "exampleSection"
}
}
}
}Consequences
The Consequences for the two approaches are described below:
1. New config inheritance:
- The inheritance can still cause incompatibility errors because of missing subsets of a dependend theme.
- The current themes will work as always but one can also add an inheritance for the config fields.
- The inhertiance will no longer be a snapshot, but a dynamic copy of the inherited themes (The changes of child themes will be considered by the new theme automaticaly)
- The admin for the themes will get an inheritation mechanism which allows users to decide if a field will use its inherited or a new value (simmiliar to productvariant inherited fields)
- Themes which are dependend on other themes than the default storefront theme, need to add the other themes into there composer.json as
requiredto prevent incomplete setups.
"require": {
"swag/previous-theme": "~1.1"
},Example complete composer.json
{
"name": "swag/my-development-theme",
"description": "My Development Theme",
"type": "shopware-platform-plugin",
"version": "1.7",
"license": "MIT",
"autoload": {
"psr-4": {
"MyDevelopmentTheme\\": "src/"
}
},
"require": {
"swag/previous-theme": "~1.1"
},
"extra": {
"shopware-plugin-class": "MyDevelopmentTheme\\MyDevelopmentTheme",
"label": {
"de-DE": "Theme MyDevelopmentTheme plugin",
"en-GB": "Theme MyDevelopmentTheme plugin"
}
}
}