uceap_logging.module

<?php

/**
 * @file
 * Provides logging for HTTP requests and entity CRUD operations.
 */

use Drupal\Core\Entity\ContentEntityInterface;
use Drupal\Core\Entity\EntityInterface;

/**
 * Implements hook_entity_insert().
 *
 * Log all content entity insertions to watchdog.
 */
function uceap_logging_entity_insert(EntityInterface $entity) {
  if (!$entity instanceof ContentEntityInterface) {
    return;
  }

  $context = _uceap_logging_build_entity_log_context($entity, 'create');
  \Drupal::logger('uceap_entity_crud')->info('Created @type (@bundle): @label (ID: @id)', $context);
}

/**
 * Implements hook_entity_update().
 *
 * Log all content entity updates to watchdog.
 */
function uceap_logging_entity_update(EntityInterface $entity) {
  if (!$entity instanceof ContentEntityInterface) {
    return;
  }

  $context = _uceap_logging_build_entity_log_context($entity, 'update');

  // Track changed fields if original entity is available.
  if (isset($entity->original) && $entity->original instanceof ContentEntityInterface) {
    $changes = _uceap_logging_get_entity_field_changes($entity, $entity->original);

    if (!empty($changes)) {
      $context['field_changes'] = $changes;
      $context['@change_count'] = count($changes);
      \Drupal::logger('uceap_entity_crud')->info('Updated @type (@bundle): @label (ID: @id) | @change_count field(s) changed', $context);
      return;
    }
  }

  \Drupal::logger('uceap_entity_crud')->info('Updated @type (@bundle): @label (ID: @id) | No field changes detected', $context);
}

/**
 * Implements hook_entity_delete().
 *
 * Log all content entity deletions to watchdog.
 */
function uceap_logging_entity_delete(EntityInterface $entity) {
  if (!$entity instanceof ContentEntityInterface) {
    return;
  }

  $context = _uceap_logging_build_entity_log_context($entity, 'delete');
  \Drupal::logger('uceap_entity_crud')->warning('Deleted @type (@bundle): @label (ID: @id)', $context);
}

/**
 * Build structured logging context for entity operations.
 *
 * @param \Drupal\Core\Entity\ContentEntityInterface $entity
 *   The entity being logged.
 * @param string $operation
 *   The operation type: 'create', 'update', or 'delete'.
 *
 * @return array
 *   Context array for logger with both message placeholders and structured data.
 */
function _uceap_logging_build_entity_log_context(ContentEntityInterface $entity, string $operation) {
  $entity_type = $entity->getEntityTypeId();
  $bundle = $entity->bundle();
  $label = $entity->label() ?: 'N/A';
  $id = $entity->id();

  return [
    // Message placeholders (prefixed with @).
    '@type' => $entity_type,
    '@bundle' => $bundle,
    '@label' => $label,
    '@id' => $id,
    // Structured data for CloudWatch (no prefix).
    'entity_type' => $entity_type,
    'bundle' => $bundle,
    'entity_id' => $id,
    'operation' => $operation,
  ];
}

/**
 * Get changed fields between two entity states.
 *
 * @param \Drupal\Core\Entity\ContentEntityInterface $entity
 *   The updated entity.
 * @param \Drupal\Core\Entity\ContentEntityInterface $original
 *   The original entity.
 *
 * @return array
 *   Array of changes keyed by field name, with 'old' and 'new' values.
 */
function _uceap_logging_get_entity_field_changes(ContentEntityInterface $entity, ContentEntityInterface $original) {
  // Fields to completely exclude from change tracking.
  $excluded_fields = [
    'changed',
    'revision_timestamp',
    'revision_translation_affected',
    'revision_uid',
    'revision_log',
  ];

  // Sensitive fields that should have values masked in logs.
  $config = \Drupal::config('uceap_logging.settings');
  $sensitive_fields = $config->get('sensitive_fields') ?? [];

  $changes = [];
  $field_definitions = $entity->getFieldDefinitions();

  foreach ($field_definitions as $field_name => $field_definition) {
    // Skip computed and internal fields (they are derived values).
    if ($field_definition->isComputed() || $field_definition->isInternal()) {
      continue;
    }

    // Skip excluded fields entirely.
    if (in_array($field_name, $excluded_fields)) {
      continue;
    }

    // Check if field exists on both entities.
    if (!$entity->hasField($field_name) || !$original->hasField($field_name)) {
      continue;
    }

    $new_value = $entity->get($field_name)->getValue();
    $old_value = $original->get($field_name)->getValue();

    // Compare values.
    if ($new_value !== $old_value) {
      // Mask sensitive field values instead of skipping them.
      $is_sensitive = in_array($field_name, $sensitive_fields);

      $changes[$field_name] = [
        'old' => $is_sensitive ? '****MASKED****' : _uceap_logging_format_field_value($old_value),
        'new' => $is_sensitive ? '****MASKED****' : _uceap_logging_format_field_value($new_value),
      ];
    }
  }

  return $changes;
}

/**
 * Helper function to format field values for logging.
 *
 * @param mixed $value
 *   The field value (typically an array from getValue()).
 *
 * @return string
 *   A formatted string representation of the value.
 */
function _uceap_logging_format_field_value($value) {
  if (empty($value)) {
    return 'empty';
  }

  // If it's an array, format it appropriately.
  if (is_array($value)) {
    // For single-value fields, just show the value.
    if (count($value) === 1 && isset($value[0])) {
      $item = $value[0];
      // Handle common field types.
      if (isset($item['value'])) {
        // Truncate long text values.
        $val = (string) $item['value'];
        return strlen($val) > 100 ? substr($val, 0, 100) . '...' : $val;
      }
      elseif (isset($item['target_id'])) {
        return "ID:{$item['target_id']}";
      }
      elseif (isset($item['uri'])) {
        return $item['uri'];
      }
      else {
        // For other complex items, show key fields.
        $parts = [];
        foreach ($item as $key => $val) {
          if (!is_array($val) && !is_object($val)) {
            $parts[] = "$key:$val";
          }
        }
        return implode(',', $parts);
      }
    }
    // For multi-value fields, show count and summary.
    else {
      $count = count($value);
      $first_item = reset($value);
      if (isset($first_item['target_id'])) {
        $ids = array_column($value, 'target_id');
        return "$count items [IDs:" . implode(',', array_slice($ids, 0, 5)) . (count($ids) > 5 ? '...' : '') . ']';
      }
      elseif (isset($first_item['value'])) {
        return "$count values";
      }
      else {
        return "$count items";
      }
    }
  }

  // For scalar values.
  $str = (string) $value;
  return strlen($str) > 100 ? substr($str, 0, 100) . '...' : $str;
}