FieldWidget's XB transforms must be bubbled by the Field Widget rendering to inform the client

But after data has been stored, prop shape matching can be modified by installing new modules/field types.
And the representation of the data in the component config entity can change.

But that only dictates the field type + widget to use for new component instances.

All existing component instances do NOT change. That's why all that information (field type + storage settings + instance settings + widget) is self-contained in the \Drupal\experience_builder\PropSource\StaticPropSource and stored for every prop of every instance of every SDC-like component.

@lauriii once created an issue with a mock-up many months ago, early during the life of XB, to indicate what he thought the UX should be to allow the content creator to "update" to the new default StaticPropSource for an SDC prop.

Instead of keeping transforms in the component list under the field data for each prop, send a list of transforms per source type in drupalSettings or an API and use the sourceType (which we have available) in the clientside code to find the transforms to apply based on the stored sourceType rather than the current one

Ahhhh … 🙈 So this is about

    "transforms": {
      "text": {
        "mainProperty": [
          
        ]
      }

And not about StaticPropSources and what data they contain — it's about those two getting out of sync! IOW: this is a bug we unwittingly introduced in #3499554: Move client-side assumptions about prop form data shape into a series of prop-specific transforms 😬🙈

+1 for this being stable-blocking. But shouldn't it be per widget instead of "per sourceType"?

#12: Thanks, #3463996 was indeed the issue I was looking for but could not find! 😄

#9:

We do for the sourceType which should map 1:1 to the widget via the prop shape.

But per \Drupal\experience_builder\PropSource\StaticPropSource::getSourceType(), that's not sufficient, because sourceType does not track storage + instance settings.

Example:

      // @see \Drupal\datetime\Plugin\Field\FieldType\DateTimeItem
      static::DATE_TIME => new StorablePropShape(shape: $shape, fieldTypeProp: new FieldTypePropExpression('datetime', 'value'), fieldStorageSettings: ['datetime_type' => DateTimeItem::DATETIME_TYPE_DATETIME], fieldWidget: 'datetime_default'),
      // @see \Drupal\datetime\Plugin\Field\FieldType\DateTimeItem
      static::DATE => new StorablePropShape(shape: $shape, fieldTypeProp: new FieldTypePropExpression('datetime', 'value'), fieldStorageSettings: ['datetime_type' => DateTimeItem::DATETIME_TYPE_DATE], fieldWidget: 'datetime_default'),

— \Drupal\experience_builder\JsonSchemaInterpreter\JsonSchemaStringFormat::computeStorablePropShape()

Both have the same sourceType, but with different storage settings. They currently happen to use the same field widget, but that is not necessarily the case.

#10: XB prior to #3493943 always using the default static prop source was indeed also wrong, for the reason you say: it always ignored the stored one. #3499554 was great! But it can only work as long as every SDC prop shape forever uses the same field widget (and presumably the same field type + storage settings + instance settings).

That's the point I tried to make in #6, but there's too much noise around it, sorry! 🙈

Digging deeper into how this works today:

• \Drupal\experience_builder\PropSource\StaticPropSource::getWidget() has an optional $field_widget_plugin_id parameter, but we don't use it today except in tests.
• The logic that determines the field widget is littered with @todos and most of it was introduced in August 2024 in #3462709: Introduce `hook_storable_prop_shape_alter()`, use it to prefer the Media Library widget for "image" PropShape if Media Library is installed (in ComponentPropsForm back then):
  

        // 1. If the given static prop source matches the *current* field type
        // configuration, use the configured widget.
        // 2. Worst case: fall back to the default widget for this field type.
        // @todo Implement 2. in https://www.drupal.org/project/experience_builder/issues/3463996
        $field_widget_plugin_id = NULL;
        if ($source->getSourceType() === 'static:field_item:' . $prop_field_definitions[$sdc_prop_name]['field_type']) {
          $field_widget_plugin_id = $prop_field_definitions[$sdc_prop_name]['field_widget'];
        }
        assert(isset($component_schema['properties'][$sdc_prop_name]['title']));
        $label = $component_schema['properties'][$sdc_prop_name]['title'];
        $is_required = isset($component_schema['required']) && in_array($sdc_prop_name, $component_schema['required'], TRUE);
        $form[$sdc_prop_name] = $source->formTemporaryRemoveThisExclamationExclamationExclamation($field_widget_plugin_id, $sdc_prop_name, $label, $is_required, $entity, $form, $form_state);
  

AFAICT we have two possible choices:

1. The client-side transforms really are for widget (hence // Build transforms from widget metadata.). The bug you reported here is possible we pass the xb.transforms metadata out-of-band: we pass it as one bit of metadata for all available XB components (the /xb/api/config/component response). But actually, that API response dictates the current storage choices for prop shapes, not old ones. That's where the mismatch happens.

   If we'd stop passing that information there, but instead pass that information via data- attributes or drupalSettings (or some other mechanism) in \Drupal\experience_builder\Plugin\ExperienceBuilder\ComponentSource\GeneratedFieldExplicitInputUxComponentSourceBase::buildConfigurationForm(), then we'd bypass that out-of-syncness.

2. Alternatively, we basically solve #3463996: [META] When the field type, storage/instance settings, widget, expression or requiredness for an SDC/code component prop changes, the Content Creator must be able to upgrade, but without supporting adapters. (Adapters make it hard. But nothing can use adapters today — it's only used internally in tests to prove it is possible.)

   Because:

   •     cta1href:
           type: string
           format: uri
           title: CTA 1 link
           examples:
             - https://example.com
     

     is clear about what it needs: a URI

   • The initial storable prop shape for it is:
     

       cta1href:
           field_type: link
           field_storage_settings: {  }
           field_instance_settings:
             title: 0
           field_widget: link_default
           default_value:
             uri: 'https://example.com'
             options: {  }
           expression: ℹ︎link␟uri
      

     which is clear about where that value is stored: the uri prop of the link field type

   • Similarly, the updated/new storable prop shape for it is:
     

       cta1href:
           field_type: uri
           field_storage_settings: {  }
           field_instance_settings: {  }
           field_widget: uri
           default_value:
             value: 'https://example.com'
           expression: ℹ︎uri␟value
     

     which is also clear about where that value is stored: the value prop of the uri field type

   • Which means that I think we can basically do the following upon editing:
     

     diff --git a/src/Plugin/ExperienceBuilder/ComponentSource/GeneratedFieldExplicitInputUxComponentSourceBase.php b/src/Plugin/ExperienceBuilder/ComponentSource/GeneratedFieldExplicitInputUxComponentSourceBase.php
     index a52658f62..3aaae6dfb 100644
     --- a/src/Plugin/ExperienceBuilder/ComponentSource/GeneratedFieldExplicitInputUxComponentSourceBase.php
     +++ b/src/Plugin/ExperienceBuilder/ComponentSource/GeneratedFieldExplicitInputUxComponentSourceBase.php
     @@ -401,6 +401,13 @@ abstract class GeneratedFieldExplicitInputUxComponentSourceBase extends Componen
              $disabled = !$source instanceof UrlPreviewPropSource;
              $source = $this->getDefaultStaticPropSource($sdc_prop_name)->withValue($prop_source_array['value'] ?? NULL);
            }
     +      else {
     +        // Automatically update from the old recommended static prop source (as
     +        // defined in `$component->getSettings()['prop_field_definitions']` at
     +        // the time of creating this component instance) to the new one (as
     +        // currently in `$component->getSettings()['prop_field_definitions']`).
     +        $source = $this->getDefaultStaticPropSource($sdc_prop_name)->withValue($prop_source_array['value'] ?? NULL);
     +      }
            // 1. If the given static prop source matches the *current* field type
            // configuration, use the configured widget.
            // 2. Worst case: fall back to the default widget for this field type.
     

We cross-posted! :D

And you basically implemented something like #16.1. You're concerned about some parts of the MR. I agree with those concerns.

But your changes to src/Render/MainContent/XBTemplateRenderer.php provided me with some inspiration: I think it's good to keep that mechanism, but I think we can avoid relying on global variables to pass the data, by using a new #attached type instead.

Roughly something like the attached patch.

Not awaiting a review from @bnjmnm on this one because #3493941: Maintain a per-component set of prop expressions/sources was built primarily by @larowlan and @longwave, and this MR is mostly reorganizing things for clarity, not changing any fundamentals. All end-to-end tests still passing is sufficient evidence.

Actually, I'd rather have @bnjmnm +1 this given #3487284-18: [META] Add explicit end-to-end test coverage for using all core field widgets including multiple cardinalities in the "Page Data" (content entity) form — it's important multiple people thoroughly understand this 😊

I believe this reflects the pivot @larowlan implemented since #18 😊

We should update section 3.4 in docs/redux-integrated-field-widgets.md to allow new contributors to understand how this work.

Still would like @bnjmnm's +1 per #21.

Thanks @bnjmnm for reviewing after I requested that in #24 🙏 😊

@bnjmnm's 2 points of feedback have been addressed. Rather than ask Ben to context switch into this (Ben's currently working on #3520721: Page duplication in navigator results in blank title in editor panel and #3487284: [META] Add explicit end-to-end test coverage for using all core field widgets including multiple cardinalities in the "Page Data" (content entity) form) to confirm fairly trivial changes (simplifying code in one file, adding a comment in another), I'm gonna go ahead and merge.

See #3484395-32: CKEditor 5 not loading on formatted text Field Widgets in the component instance form — a tiny change here turns out to have been a distracting bug!