[2.0.0-beta4] Use a valid URI scheme and rethink FieldValueSourceBase::extractPropertyValue

Problem/Motivation

When using "Data from a field" source with a Link field, i have this error coming from FieldValueSourceBase::resolveInternalUri()
:

The URI 'public://2024-10/generateImage_K6fSfV.jpg' is invalid. You must use a valid URI scheme. Use base: for a path, e.g., to a Drupal file that needs the base path. Do not use this for internal paths controlled by Drupal

It can be fixed by doing something like that at the beginning of the method:

    $stream_wrappers = [
      "public",
      "private",
      "temp",
    ];
    $scheme = parse_url($value, PHP_URL_SCHEME);
    if (in_array($scheme, $stream_wrappers)) {
      $value = $this->fileUrlGenerator->generateAbsoluteString($value);
    }

But, I am wondering..

Do we still need FieldValueSourceBase::resolveInternalUri()?

  protected function resolveInternalUri(FieldItemInterface $item, string $value): string {
    // Most of the time, Uri datatype is met in a "link" field type.
    if ($item->getDataDefinition()->getDataType() === 'field_item:link') {
      $options = (array) $item->get('options')->getValue();
      return Url::fromUri($value, $options)->toString();
    }
    return Url::fromUri($value)->toString();
  }

Maybe the logic is better in UrlPropType::normalize()? We will lose the retrieval of $item->get('options'), but it may worth it.

Also, do we still need FieldValueSourceBase::getEntityReferencedLabel()?

  protected function getEntityReferencedLabel(EntityReference $property, string $lang_code): mixed {
    // Ensure the referenced entity still exists.
    $referencedEntityTypeId = $property->getTargetDefinition()
      ->getEntityTypeId();
    $referencedEntityId = $property->getTargetIdentifier();
    if (!$referencedEntityId) {
      return NULL;
    }
    $entity = $this->entityTypeManager
      ->getStorage($referencedEntityTypeId)
      ->load($referencedEntityId);

    if (!$entity || !is_object($entity)) {
      return NULL;
    }
    // Drupal loads the entity in its default language and should load
    // the translated one if available.
    $value = $entity->label();
    /** @var \Drupal\Core\Entity\ContentEntityInterface $entity */
    if (($entity instanceof TranslatableInterface)
      && $lang_code
      && $entity->hasTranslation($lang_code)) {
      $translated_entity = $entity->getTranslation($lang_code);
      $value = $translated_entity->label();
    }
    return $value;
  }

Because we have "Data from referenced entity now", so we can ignore the entity field properties, and retrieve the referenced entity label.

If we remove those methods, we may not need:

  protected function extractPropertyValue(FieldItemInterface $item, string $property_name, string $lang_code): mixed {
    $property = $item->get($property_name);
    if ($property instanceof TextProcessed) {
      return $property->getValue();
    }
    if ($property instanceof EntityReference) {
      return $this->getEntityReferencedLabel($property, $lang_code);
    }

    $value = $property->getValue();
    if ($value && ($property instanceof Uri)) {
      // $value is a non-empty string.
      return $this->resolveInternalUri($item, $value);
    }
    return $value;
  }

Because TextProcessed typed data logic looks useless.

Proposed resolution

Let's discuss.