clean install

web/modules/jsonapi_extras/src/Plugin/DateTimeEnhancerBase.php

@@ -0,0 +1,46 @@
+<?php
+
+namespace Drupal\jsonapi_extras\Plugin;
+
+/**
+ * Base class for date and time based resourceFieldEnhancer plugins.
+ */
+abstract class DateTimeEnhancerBase extends ResourceFieldEnhancerBase {
+
+  /**
+   * {@inheritdoc}
+   */
+  public function defaultConfiguration() {
+    return [
+      'dateTimeFormat' => \DateTime::ISO8601,
+    ];
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function getOutputJsonSchema() {
+    return [
+      'type' => 'string',
+    ];
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function getSettingsForm(array $resource_field_info) {
+    $settings = empty($resource_field_info['enhancer']['settings'])
+      ? $this->getConfiguration()
+      : $resource_field_info['enhancer']['settings'];
+
+    return [
+      'dateTimeFormat' => [
+        '#type' => 'textfield',
+        '#title' => $this->t('Format'),
+        '#description' => $this->t('Use a valid date format.'),
+        '#default_value' => $settings['dateTimeFormat'],
+      ],
+    ];
+  }
+
+}

web/modules/jsonapi_extras/src/Plugin/ResourceFieldEnhancerBase.php

@@ -0,0 +1,96 @@
+<?php
+
+namespace Drupal\jsonapi_extras\Plugin;
+
+use Drupal\Core\Plugin\PluginBase;
+use JsonSchema\Constraints\Constraint;
+use JsonSchema\Validator;
+use Shaper\DataAdaptor\DataAdaptorTransformerTrait;
+use Shaper\DataAdaptor\DataAdaptorValidatorTrait;
+use Shaper\Validator\AcceptValidator;
+use Shaper\Validator\JsonSchemaValidator;
+
+/**
+ * Common base class for resourceFieldEnhancer plugins.
+ *
+ * @see \Drupal\jsonapi_extras\Annotation\ResourceFieldEnhancer
+ * @see \Drupal\jsonapi_extras\Plugin\ResourceFieldEnhancerManager
+ * @see \Drupal\jsonapi_extras\Plugin\ResourceFieldEnhancerInterface
+ * @see plugin_api
+ *
+ * @ingroup third_party
+ */
+abstract class ResourceFieldEnhancerBase extends PluginBase implements ResourceFieldEnhancerInterface {
+
+  use DataAdaptorValidatorTrait;
+  use DataAdaptorTransformerTrait;
+
+  /**
+   * Holds the plugin configuration.
+   *
+   * @var array
+   */
+  protected $configuration;
+
+  /**
+   * {@inheritdoc}
+   */
+  public function defaultConfiguration() {
+    return [];
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function calculateDependencies() {
+    // @todo This should have a dependency on the resource_config entity.
+    return [];
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function getConfiguration() {
+    return $this->configuration
+      ? $this->configuration
+      : $this->setConfiguration([]);
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function setConfiguration(array $configuration) {
+    $this->configuration = $configuration + $this->defaultConfiguration();
+    return $this->configuration;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function getSettingsForm(array $resource_field_info) {
+    return [];
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function getInternalValidator() {
+    return new AcceptValidator();
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function getInputValidator() {
+    // @todo Implement a getInputJsonSchema method.
+    return new AcceptValidator();
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function getOutputValidator() {
+    return new JsonSchemaValidator($this->getOutputJsonSchema(), new Validator(), Constraint::CHECK_MODE_TYPE_CAST);
+  }
+
+}

web/modules/jsonapi_extras/src/Plugin/ResourceFieldEnhancerInterface.php

@@ -0,0 +1,34 @@
+<?php
+
+namespace Drupal\jsonapi_extras\Plugin;
+
+use Shaper\DataAdaptor\ReversibleTransformationInterface;
+use Shaper\DataAdaptor\ReversibleTransformationValidationInterface;
+use Shaper\Transformation\TransformationInterface;
+use Shaper\Transformation\TransformationValidationInterface;
+
+/**
+ * Provides an interface defining a ResourceFieldEnhancer entity.
+ */
+interface ResourceFieldEnhancerInterface extends TransformationInterface, ReversibleTransformationInterface, TransformationValidationInterface, ReversibleTransformationValidationInterface {
+
+  /**
+   * Get the JSON Schema for the new output.
+   *
+   * @return array
+   *   An structured array representing the JSON Schema of the new output.
+   */
+  public function getOutputJsonSchema();
+
+  /**
+   * Get a form element to render the settings.
+   *
+   * @param array $resource_field_info
+   *   The resource field info.
+   *
+   * @return array
+   *   The form element array.
+   */
+  public function getSettingsForm(array $resource_field_info);
+
+}

web/modules/jsonapi_extras/src/Plugin/ResourceFieldEnhancerManager.php

@@ -0,0 +1,61 @@
+<?php
+
+namespace Drupal\jsonapi_extras\Plugin;
+
+use Drupal\Core\Cache\CacheBackendInterface;
+use Drupal\Core\Extension\ModuleHandlerInterface;
+use Drupal\Core\Plugin\DefaultPluginManager;
+
+/**
+ * Manages discovery and instantiation of resourceFieldEnhancer plugins.
+ */
+class ResourceFieldEnhancerManager extends DefaultPluginManager {
+
+  /**
+   * Constructs a new ResourceFieldEnhancerManager.
+   *
+   * @param \Traversable $namespaces
+   *   An object that implements \Traversable which contains the root paths
+   *   keyed by the corresponding namespace to look for plugin implementations.
+   * @param \Drupal\Core\Cache\CacheBackendInterface $cache_backend
+   *   Cache backend instance to use.
+   * @param \Drupal\Core\Extension\ModuleHandlerInterface $module_handler
+   *   The module handler to invoke the alter hook with.
+   */
+  public function __construct(\Traversable $namespaces, CacheBackendInterface $cache_backend, ModuleHandlerInterface $module_handler) {
+    parent::__construct(
+      'Plugin/jsonapi/FieldEnhancer',
+      $namespaces,
+      $module_handler,
+      'Drupal\jsonapi_extras\Plugin\ResourceFieldEnhancerInterface',
+      'Drupal\jsonapi_extras\Annotation\ResourceFieldEnhancer'
+    );
+
+    $this->alterInfo('resource_field_enhancer_info');
+    $this->setCacheBackend($cache_backend, 'resource_field_enhancer_plugins');
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  protected function alterDefinitions(&$definitions) {
+    // Loop through all definitions.
+    foreach ($definitions as $definition_key => $definition_info) {
+      // Check to see if dependencies key is set.
+      if (!empty($definition_info['dependencies'])) {
+        $definition_dependencies = $definition_info['dependencies'];
+        // Loop through dependencies to confirm if enabled.
+        foreach ($definition_dependencies as $dependency) {
+          // If dependency is not enabled removed from list of definitions.
+          if (!$this->moduleHandler->moduleExists($dependency)) {
+            unset($definitions[$definition_key]);
+            continue;
+          }
+        }
+      }
+    }
+
+    parent::alterDefinitions($definitions);
+  }
+
+}

web/modules/jsonapi_extras/src/Plugin/Validation/Constraint/DuplicateFieldConstraint.php

@@ -0,0 +1,24 @@
+<?php
+
+namespace Drupal\jsonapi_extras\Plugin\Validation\Constraint;
+
+use Symfony\Component\Validator\Constraint;
+
+/**
+ * The constraint object.
+ *
+ * @Constraint(
+ *   id = "jsonapi_extras__duplicate_field",
+ *   label = @Translation("Duplicate field", context = "Validation")
+ * )
+ */
+class DuplicateFieldConstraint extends Constraint {
+
+  /**
+   * The error message for the constraint.
+   *
+   * @var string
+   */
+  public $message = 'The override must be unique.';
+
+}

web/modules/jsonapi_extras/src/Plugin/Validation/Constraint/DuplicateFieldConstraintValidator.php

@@ -0,0 +1,90 @@
+<?php
+
+namespace Drupal\jsonapi_extras\Plugin\Validation\Constraint;
+
+use Drupal\Core\Entity\EntityTypeManagerInterface;
+use Symfony\Component\Validator\Constraint;
+use Symfony\Component\Validator\ConstraintValidator;
+
+/**
+ * The validator.
+ */
+class DuplicateFieldConstraintValidator extends ConstraintValidator {
+
+  /**
+   * The entity type manager.
+   *
+   * @var \Drupal\Core\Entity\EntityTypeManagerInterface
+   */
+  protected $entityTypeManager;
+
+  /**
+   * DuplicateFieldConstraintValidator constructor.
+   */
+  public function __construct(EntityTypeManagerInterface $entityTypeManager = NULL) {
+    $this->entityTypeManager = $entityTypeManager ?: \Drupal::entityTypeManager();
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function validate($entity_data, Constraint $constraint) {
+    $resourceFields = $entity_data['resourceFields'];
+    $overrides = [];
+
+    // Get the field values.
+    foreach ($resourceFields as $field => $data) {
+      // Only get the overridden fields.
+      if ($data['fieldName'] != $data['publicName']) {
+        // Store the publicName for comparison.
+        $overrides[$field] = $data['publicName'];
+      }
+    }
+
+    // Compare the overrides and find any duplicate values.
+    $deduped_overrides = array_unique($overrides);
+    $dupes = array_diff_assoc($overrides, $deduped_overrides);
+    // Set an error if there are duplicates.
+    if ($dupes) {
+      foreach ($dupes as $field => $value) {
+        $this->context->buildViolation($constraint->message)
+          ->atPath("resourceFields.$field.publicName")
+          ->addViolation();
+      }
+    }
+    // Now compare the overrides with the default names to validate no dupes
+    // exist.
+    foreach ($overrides as $field => $override) {
+      if (array_key_exists($override, $resourceFields)) {
+        $this->context->buildViolation($constraint->message)
+          ->atPath("resourceFields.$field.publicName")
+          ->addViolation();
+      }
+    }
+
+    // Validate URL and resource type.
+    $resource_types = $this->entityTypeManager
+      ->getStorage('jsonapi_resource_config')
+      ->loadByProperties(['disabled' => FALSE]);
+    foreach ($resource_types as $id => $resource_type) {
+      if ($entity_data['id'] == $id) {
+        continue;
+      }
+
+      if ($resource_type->get('resourceType') == $entity_data['resourceType']) {
+        $this->context->buildViolation(
+          'There is already resource (@name) with this resource type.',
+          ['@name' => $resource_type->id()]
+        )
+          ->atPath('resourceType')
+          ->addViolation();
+      }
+      if ($resource_type->get('path') == $entity_data['path']) {
+        $this->context->buildViolation('There is already resource (@name) with this path.', ['@name' => $resource_type->id()])
+          ->atPath('resourceType')
+          ->addViolation();
+      }
+    }
+  }
+
+}

web/modules/jsonapi_extras/src/Plugin/jsonapi/FieldEnhancer/DateTimeEnhancer.php

@@ -0,0 +1,43 @@
+<?php
+
+namespace Drupal\jsonapi_extras\Plugin\jsonapi\FieldEnhancer;
+
+use Drupal\Core\Datetime\DrupalDateTime;
+use Drupal\jsonapi_extras\Plugin\DateTimeEnhancerBase;
+use Shaper\Util\Context;
+
+/**
+ * Perform additional manipulations to timestamp fields.
+ *
+ * @ResourceFieldEnhancer(
+ *   id = "date_time",
+ *   label = @Translation("Date Time (Timestamp field)"),
+ *   description = @Translation("Formats a date based the configured date format for timestamp fields."),
+ *   dependencies = {"datetime"}
+ * )
+ */
+class DateTimeEnhancer extends DateTimeEnhancerBase {
+
+  /**
+   * {@inheritdoc}
+   */
+  protected function doUndoTransform($data, Context $context) {
+    $date = new \DateTime();
+    $date->setTimestamp(is_int($data)
+      ? $data
+      : (new DrupalDateTime($data))->getTimestamp()
+    );
+    $configuration = $this->getConfiguration();
+
+    return $date->format($configuration['dateTimeFormat']);
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  protected function doTransform($data, Context $context) {
+    $date = new \DateTime($data);
+    return (int) $date->format('U');
+  }
+
+}

web/modules/jsonapi_extras/src/Plugin/jsonapi/FieldEnhancer/DateTimeFromStringEnhancer.php

@@ -0,0 +1,84 @@
+<?php
+
+namespace Drupal\jsonapi_extras\Plugin\jsonapi\FieldEnhancer;
+
+use Drupal\datetime\Plugin\Field\FieldType\DateTimeItemInterface;
+use Drupal\jsonapi_extras\Plugin\DateTimeEnhancerBase;
+use Shaper\Util\Context;
+
+/**
+ * Perform additional manipulations to datetime fields.
+ *
+ * @ResourceFieldEnhancer(
+ *   id = "date_time_from_string",
+ *   label = @Translation("Date Time (Date Time field)"),
+ *   description = @Translation("Formats a date based the configured date format for date fields."),
+ *   dependencies = {"datetime"}
+ * )
+ */
+class DateTimeFromStringEnhancer extends DateTimeEnhancerBase {
+
+  /**
+   * {@inheritdoc}
+   */
+  protected function doUndoTransform($data, Context $context) {
+    $configuration = $this->getConfiguration();
+
+    $reformat = function ($input) use ($configuration) {
+      $storage_timezone = new \DateTimezone(DateTimeItemInterface::STORAGE_TIMEZONE);
+      $date = new \DateTime($input, $storage_timezone);
+
+      $output_timezone = new \DateTimezone(date_default_timezone_get());
+      $date->setTimezone($output_timezone);
+      $output = $date->format($configuration['dateTimeFormat']);
+
+      return $output;
+    };
+
+    $result = is_array($data) ? array_map($reformat, $data) : $reformat($data);
+
+    return $result;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  protected function doTransform($data, Context $context) {
+    $reformat = function ($input) {
+      $date = new \DateTime($input);
+
+      // Adjust the date for storage.
+      $storage_timezone = new \DateTimezone(DateTimeItemInterface::STORAGE_TIMEZONE);
+      $date->setTimezone($storage_timezone);
+      $output = $date->format(DateTimeItemInterface::DATETIME_STORAGE_FORMAT);
+
+      return $output;
+    };
+
+    $result = is_array($data) ? array_map($reformat, $data) : $reformat($data);
+
+    return $result;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function getOutputJsonSchema() {
+    $baseType = parent::getOutputJsonSchema();
+
+    return [
+      "anyOf" => [
+        $baseType,
+        ["type" => "array", "items" => $baseType],
+        [
+          "type" => "object",
+          "properties" => [
+            "value" => $baseType,
+            "end_value" => $baseType,
+          ],
+        ],
+      ],
+    ];
+  }
+
+}

web/modules/jsonapi_extras/src/Plugin/jsonapi/FieldEnhancer/JSONFieldEnhancer.php

@@ -0,0 +1,94 @@
+<?php
+
+namespace Drupal\jsonapi_extras\Plugin\jsonapi\FieldEnhancer;
+
+use Drupal\Component\Serialization\Json;
+use Drupal\Core\Plugin\ContainerFactoryPluginInterface;
+use Drupal\jsonapi_extras\Plugin\ResourceFieldEnhancerBase;
+use Shaper\Util\Context;
+use Symfony\Component\DependencyInjection\ContainerInterface;
+
+/**
+ * Perform additional manipulations to JSON fields.
+ *
+ * @ResourceFieldEnhancer(
+ *   id = "json",
+ *   label = @Translation("JSON Field"),
+ *   description = @Translation("Render JSON Field has real json")
+ * )
+ */
+class JSONFieldEnhancer extends ResourceFieldEnhancerBase implements ContainerFactoryPluginInterface {
+
+  /**
+   * The serialization json.
+   *
+   * @var Drupal\Component\serialization\Json
+   */
+  protected $encoder;
+
+  /**
+   * Constructs a new JSONFieldEnhancer.
+   *
+   * @param array $configuration
+   *   A configuration array containing information about the plugin instance.
+   * @param string $plugin_id
+   *   The plugin_id for the plugin instance.
+   * @param mixed $plugin_definition
+   *   The plugin implementation definition.
+   * @param \Drupal\Component\Serialization\Json $encoder
+   *   The serialization json.
+   */
+  public function __construct(array $configuration, string $plugin_id, $plugin_definition, Json $encoder) {
+    parent::__construct($configuration, $plugin_id, $plugin_definition);
+    $this->encoder = $encoder;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public static function create(ContainerInterface $container, array $configuration, $plugin_id, $plugin_definition) {
+    return new static($configuration, $plugin_id, $plugin_definition, $container->get('serialization.json'));
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function defaultConfiguration() {
+    return [];
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function doUndoTransform($data, Context $context) {
+    return $this->encoder->decode($data);
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  protected function doTransform($data, Context $context) {
+    return $this->encoder->encode($data);
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function getOutputJsonSchema() {
+    return [
+      'oneOf' => [
+        ['type' => 'object'],
+        ['type' => 'array'],
+        ['type' => 'null'],
+      ],
+    ];
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function getSettingsForm(array $resource_field_info) {
+    return [];
+  }
+
+}

web/modules/jsonapi_extras/src/Plugin/jsonapi/FieldEnhancer/ListFieldEnhancer.php

@@ -0,0 +1,70 @@
+<?php
+
+namespace Drupal\jsonapi_extras\Plugin\jsonapi\FieldEnhancer;
+
+use Drupal\jsonapi_extras\Plugin\ResourceFieldEnhancerBase;
+use Drupal\options\Plugin\Field\FieldType\ListItemBase;
+use Shaper\Util\Context;
+
+/**
+ * Perform additional manipulations to list fields.
+ *
+ * @ResourceFieldEnhancer(
+ *   id = "list",
+ *   label = @Translation("List Field"),
+ *   description = @Translation("Formats a list field based on labels and values.")
+ * )
+ */
+class ListFieldEnhancer extends ResourceFieldEnhancerBase {
+
+  /**
+   * {@inheritDoc}
+   */
+  protected function doTransform($data, Context $context) {
+    return is_array($data) ? array_column($data, 'value') : $data;
+  }
+
+  /**
+   * {@inheritDoc}
+   */
+  protected function doUndoTransform($data, Context $context) {
+    $field_context = $context->offsetGet('field_item_object');
+    assert($field_context instanceof ListItemBase);
+    $options = $field_context->getPossibleOptions();
+    $reformat = static function ($input) use ($options) {
+      return [
+        'value' => $input,
+        'label' => $options[(string) $input] ?? '',
+      ];
+    };
+    return is_array($data) ? array_map($reformat, $data) : $reformat($data);
+  }
+
+  /**
+   * {@inheritDoc}
+   */
+  public function getOutputJsonSchema(): array {
+    return [
+      'type' => 'array',
+      'items' => [
+        'type' => 'object',
+        'properties' => [
+          'value' => [
+            'anyOf' => [
+              ['type' => 'string'],
+              ['type' => 'number'],
+              ['type' => 'null'],
+            ],
+          ],
+          'label' => [
+            'anOf' => [
+              ['type' => 'string'],
+              ['type' => 'null'],
+            ],
+          ],
+        ],
+      ],
+    ];
+  }
+
+}

web/modules/jsonapi_extras/src/Plugin/jsonapi/FieldEnhancer/SingleNestedEnhancer.php

@@ -0,0 +1,90 @@
+<?php
+
+namespace Drupal\jsonapi_extras\Plugin\jsonapi\FieldEnhancer;
+
+use Drupal\jsonapi_extras\Plugin\ResourceFieldEnhancerBase;
+use Shaper\Util\Context;
+
+/**
+ * Perform additional manipulations to date fields.
+ *
+ * @ResourceFieldEnhancer(
+ *   id = "nested",
+ *   label = @Translation("Single Nested Property"),
+ *   description = @Translation("Extracts or wraps nested properties from an object.")
+ * )
+ */
+class SingleNestedEnhancer extends ResourceFieldEnhancerBase {
+
+  /**
+   * {@inheritdoc}
+   */
+  public function defaultConfiguration() {
+    return [
+      'path' => 'value',
+    ];
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  protected function doUndoTransform($data, Context $context) {
+    $output = $data;
+    $configuration = $this->getConfiguration();
+    $path = $configuration['path'];
+    $path_parts = explode('.', $path);
+    // Start drilling down until there are no more path parts.
+    while ($output && ($path_part = array_shift($path_parts))) {
+      $output = empty($output[$path_part])
+        ? NULL
+        : $output[$path_part];
+    }
+    return $output;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  protected function doTransform($data, Context $context) {
+    $input = $data;
+    $configuration = $this->getConfiguration();
+    $path = $configuration['path'];
+    $path_parts = explode('.', $path);
+    // Start wrapping up until there are no more path parts.
+    while ($path_part = array_pop($path_parts)) {
+      $input = [$path_part => $input];
+    }
+    return $input;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function getOutputJsonSchema() {
+    return [
+      'oneOf' => [
+        ['type' => 'string'],
+        ['type' => 'null'],
+      ],
+    ];
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function getSettingsForm(array $resource_field_info) {
+    $settings = empty($resource_field_info['enhancer']['settings'])
+      ? $this->getConfiguration()
+      : $resource_field_info['enhancer']['settings'];
+
+    return [
+      'path' => [
+        '#type' => 'textfield',
+        '#title' => $this->t('Path'),
+        '#description' => $this->t('A dot separated path to extract the sub-property.'),
+        '#default_value' => $settings['path'],
+      ],
+    ];
+  }
+
+}

web/modules/jsonapi_extras/src/Plugin/jsonapi/FieldEnhancer/UrlLinkEnhancer.php

@@ -0,0 +1,162 @@
+<?php
+
+namespace Drupal\jsonapi_extras\Plugin\jsonapi\FieldEnhancer;
+
+use Drupal\Core\Language\LanguageInterface;
+use Drupal\Core\Language\LanguageManagerInterface;
+use Drupal\Core\Logger\LoggerChannelFactoryInterface;
+use Drupal\Core\Plugin\ContainerFactoryPluginInterface;
+use Drupal\Core\Url;
+use Drupal\jsonapi_extras\Plugin\ResourceFieldEnhancerBase;
+use Shaper\Util\Context;
+use Symfony\Component\DependencyInjection\ContainerInterface;
+
+/**
+ * Add URL aliases to links.
+ *
+ * @ResourceFieldEnhancer(
+ *   id = "url_link",
+ *   label = @Translation("URL for link (link field only)"),
+ *   description = @Translation("Use Url for link fields.")
+ * )
+ */
+class UrlLinkEnhancer extends ResourceFieldEnhancerBase implements ContainerFactoryPluginInterface {
+
+  /**
+   * The language manager.
+   *
+   * @var \Drupal\Core\Language\LanguageManagerInterface
+   */
+  protected $languageManager;
+
+  /**
+   * The logger service.
+   *
+   * @var \Drupal\Core\Logger\LoggerChannelInterface
+   */
+  protected $logger;
+
+  /**
+   * Constructs UrlLinkEnhancer.
+   *
+   * @param array $configuration
+   *   A configuration array containing information about the plugin instance.
+   * @param string $plugin_id
+   *   The plugin_id for the plugin instance.
+   * @param array $plugin_definition
+   *   The plugin implementation definition.
+   * @param \Drupal\Core\Language\LanguageManagerInterface $language_manager
+   *   The language manager.
+   * @param \Drupal\Core\Logger\LoggerChannelFactoryInterface $logger_factory
+   *   The logger service.
+   */
+  public function __construct(
+    array $configuration,
+    $plugin_id,
+    array $plugin_definition,
+    LanguageManagerInterface $language_manager,
+    LoggerChannelFactoryInterface $logger_factory,
+  ) {
+    parent::__construct($configuration, $plugin_id, $plugin_definition);
+    $this->languageManager = $language_manager;
+    $this->logger = $logger_factory->get('jsonapi_extras');
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public static function create(ContainerInterface $container, array $configuration, $plugin_id, $plugin_definition) {
+    return new static(
+      $configuration,
+      $plugin_id,
+      $plugin_definition,
+      $container->get('language_manager'),
+      $container->get('logger.factory')
+    );
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function defaultConfiguration() {
+    return [
+      'absolute_url' => 0,
+    ];
+  }
+
+  /**
+   * {@inheritDoc}
+   */
+  public function getSettingsForm(array $resource_field_info) {
+    $settings = empty($resource_field_info['enhancer']['settings'])
+      ? $this->getConfiguration()
+      : $resource_field_info['enhancer']['settings'];
+    $form = parent::getSettingsForm($resource_field_info);
+    $form['absolute_url'] = [
+      '#type' => 'checkbox',
+      '#title' => $this->t('Get Absolute Urls'),
+      '#default_value' => $settings['absolute_url'],
+    ];
+
+    return $form;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  protected function doUndoTransform($data, Context $context) {
+    if (isset($data['uri'])) {
+      try {
+        $url = Url::fromUri($data['uri'], ['language' => $this->languageManager->getCurrentLanguage(LanguageInterface::TYPE_CONTENT)]);
+
+        // Use absolute urls if configured.
+        $configuration = $this->getConfiguration();
+        if ($configuration['absolute_url']) {
+          $url->setAbsolute(TRUE);
+        }
+
+        $data['url'] = $url->toString();
+      }
+      catch (\Exception $e) {
+        $this->logger->error('Failed to create a URL from uri @uri. Error: @error', [
+          '@uri' => $data['uri'],
+          '@error' => $e->getMessage(),
+        ]);
+      }
+    }
+
+    return $data;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  protected function doTransform($value, Context $context) {
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function getOutputJsonSchema() {
+    return [
+      'type' => 'object',
+      'properties' => [
+        'uri' => ['type' => 'string'],
+        'title' => [
+          'anyOf' => [
+            ['type' => 'null'],
+            ['type' => 'string'],
+          ],
+        ],
+        'options' => [
+          'anyOf' => [
+            ['type' => 'array'],
+            ['type' => 'object'],
+          ],
+        ],
+        'url' => ['type' => 'string'],
+      ],
+    ];
+  }
+
+}

web/modules/jsonapi_extras/src/Plugin/jsonapi/FieldEnhancer/UuidLinkEnhancer.php

@@ -0,0 +1,111 @@
+<?php
+
+namespace Drupal\jsonapi_extras\Plugin\jsonapi\FieldEnhancer;
+
+use Drupal\Core\Entity\EntityTypeManagerInterface;
+use Drupal\Core\Plugin\ContainerFactoryPluginInterface;
+use Drupal\jsonapi_extras\Plugin\ResourceFieldEnhancerBase;
+use Shaper\Util\Context;
+use Symfony\Component\DependencyInjection\ContainerInterface;
+
+/**
+ * Use UUID for internal link field value.
+ *
+ * @ResourceFieldEnhancer(
+ *   id = "uuid_link",
+ *   label = @Translation("UUID for link (link field only)"),
+ *   description = @Translation("Use UUID for internal link field.")
+ * )
+ */
+class UuidLinkEnhancer extends ResourceFieldEnhancerBase implements ContainerFactoryPluginInterface {
+
+  /**
+   * The entity type manager.
+   *
+   * @var \Drupal\Core\Entity\EntityTypeManagerInterface
+   */
+  protected $entityTypeManager;
+
+  /**
+   * {@inheritdoc}
+   */
+  public function __construct(array $configuration, $plugin_id, array $plugin_definition, EntityTypeManagerInterface $entity_type_manager) {
+    parent::__construct($configuration, $plugin_id, $plugin_definition);
+    $this->entityTypeManager = $entity_type_manager;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public static function create(ContainerInterface $container, array $configuration, $plugin_id, $plugin_definition) {
+    return new static(
+      $configuration,
+      $plugin_id,
+      $plugin_definition,
+      $container->get('entity_type.manager')
+    );
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  protected function doUndoTransform($data, Context $context) {
+    if (isset($data['uri'])) {
+      // Check if it is a link to an entity.
+      preg_match("/entity:(.*)\/(.*)/", $data['uri'], $parsed_uri);
+      if (!empty($parsed_uri)) {
+        $entity_type = $parsed_uri[1];
+        $entity_id = $parsed_uri[2];
+        $entity = $this->entityTypeManager->getStorage($entity_type)->load($entity_id);
+        if (!is_null($entity)) {
+          $data['uri'] = 'entity:' . $entity_type . '/' . $entity->bundle() . '/' . $entity->uuid();
+        }
+        // Remove the value.
+        else {
+          $data = [
+            'uri' => '',
+            'title' => '',
+            'options' => [],
+          ];
+        }
+      }
+    }
+
+    return $data;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  protected function doTransform($value, Context $context) {
+    if (isset($value['uri'])) {
+      // Check if it is a link to an entity.
+      preg_match("/entity:(.*)\/(.*)\/(.*)/", $value['uri'], $parsed_uri);
+      if (!empty($parsed_uri)) {
+        $entity_type = $parsed_uri[1];
+        $entity_uuid = $parsed_uri[3];
+        $entities = $this->entityTypeManager->getStorage($entity_type)->loadByProperties(['uuid' => $entity_uuid]);
+        if (!empty($entities)) {
+          $entity = array_shift($entities);
+          $value['uri'] = 'entity:' . $entity_type . '/' . $entity->id();
+        }
+        else {
+          // If the entity has not been imported yet we unset the field value.
+          $value = [];
+        }
+      }
+    }
+
+    return $value;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function getOutputJsonSchema() {
+    return [
+      'type' => 'object',
+    ];
+  }
+
+}