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redis-queue.php

@@ -14,12 +14,16 @@
  * Domain Path:       /languages
  * Update URI:        false
  */
+// Exit if accessed directly.
 if ( ! defined( 'ABSPATH' ) ) {
 	exit;
 }
 
+// Plugin version and requirements.
 define( 'REDIS_QUEUE_VERSION', '2.0.0' );
 define( 'REDIS_QUEUE_MIN_PHP', '8.3' );
+
+// Plugin file paths and URLs.
 define( 'REDIS_QUEUE_PLUGIN_FILE', __FILE__ );
 define( 'REDIS_QUEUE_PLUGIN_BASENAME', plugin_basename( __FILE__ ) );
 define( 'REDIS_QUEUE_PLUGIN_DIR', plugin_dir_path( __FILE__ ) );
@@ -33,31 +37,52 @@
 
 /**
  * One-time migration of options from old prefix redis_queue_demo_ to redis_queue_.
+ *
+ * Migrates plugin options from the old naming convention (redis_queue_demo_*)
+ * to the new naming convention (redis_queue_*). This runs once during plugin
+ * upgrade from version 1.x to 2.0.0.
  */
 function redis_queue_migrate_options_v2() {
+	// Check if migration has already been performed.
 	if ( get_option( 'redis_queue_migrated_options_v2' ) ) {
 		return;
 	}
+
+	// Define all option keys that need to be migrated.
 	$option_suffixes = [
 		'redis_host', 'redis_port', 'redis_password', 'redis_database', 'default_queue', 'max_jobs_per_run',
 		'worker_timeout', 'max_retries', 'retry_backoff', 'enable_logging', 'cleanup_completed_jobs', 'cleanup_after_days',
 	];
+
+	// Migrate each option from old to new key name.
 	foreach ( $option_suffixes as $suffix ) {
 		$old_key = 'redis_queue_demo_' . $suffix;
 		$new_key = 'redis_queue_' . $suffix;
 		$old_val = get_option( $old_key, null );
+
+		// Only migrate if old value exists and new value doesn't exist.
 		if ( $old_val !== null && get_option( $new_key, null ) === null ) {
 			update_option( $new_key, $old_val );
 		}
 	}
+
+	// Mark migration as complete.
 	update_option( 'redis_queue_migrated_options_v2', '1' );
 }
 add_action( 'plugins_loaded', 'redis_queue_migrate_options_v2', 1 );
 
-// Bootstrap namespaced main class (new namespace & class name).
+/**
+ * Bootstrap the main plugin class.
+ *
+ * Initializes the Redis Queue plugin if all dependencies are loaded.
+ * If dependencies are missing (e.g., Composer autoloader not run),
+ * displays an admin notice to inform the user.
+ */
 if ( class_exists( 'Soderlind\RedisQueue\Core\Redis_Queue' ) ) {
+	// Initialize the plugin singleton instance.
 	Soderlind\RedisQueue\Core\Redis_Queue::get_instance();
 } else {
+	// Show error notice if dependencies are missing.
 	add_action( 'admin_notices', function() {
 		if ( current_user_can( 'activate_plugins' ) ) {
 			echo '<div class="notice notice-error"><p>';
@@ -68,13 +93,32 @@ function redis_queue_migrate_options_v2() {
 	} );
 }
 
+/**
+ * Get the main plugin instance.
+ *
+ * Provides global access to the Redis Queue plugin singleton instance.
+ * This is the recommended way to access the plugin's public API.
+ *
+ * @return \Soderlind\RedisQueue\Core\Redis_Queue|null Plugin instance or null if not loaded.
+ */
 function redis_queue() {
 	if ( class_exists( 'Soderlind\RedisQueue\Core\Redis_Queue' ) ) {
 		return Soderlind\RedisQueue\Core\Redis_Queue::get_instance();
 	}
 	return null;
 }
 
+/**
+ * Enqueue a background job.
+ *
+ * Convenience function to add a job to the Redis queue. This is a wrapper
+ * around the main plugin's enqueue_job method.
+ *
+ * @param string $job_type The type of job (email, image_processing, api_sync, or custom).
+ * @param array  $payload  Job-specific data to be processed.
+ * @param array  $options  Optional settings: priority, queue, delay.
+ * @return string|false Job ID on success, false on failure.
+ */
 function redis_queue_enqueue_job( $job_type, $payload = array(), $options = array() ) {
 	$instance = redis_queue();
 	if ( ! $instance ) {
@@ -83,11 +127,23 @@ function redis_queue_enqueue_job( $job_type, $payload = array(), $options = arra
 	return $instance->enqueue_job( $job_type, $payload, $options );
 }
 
+/**
+ * Process queued jobs synchronously.
+ *
+ * Creates a synchronous worker and processes jobs from the specified queue(s).
+ * This can be called from WP-CLI, cron jobs, or custom worker scripts.
+ *
+ * @param string|array $queue    Queue name(s) to process. Default 'default'.
+ * @param int|null     $max_jobs Maximum number of jobs to process. Default from settings.
+ * @return array|false Processing results array or false on failure.
+ */
 function redis_queue_process_jobs( $queue = 'default', $max_jobs = null ) {
 	$instance = redis_queue();
 	if ( ! $instance || ! $instance->get_queue_manager() || ! $instance->get_job_processor() ) {
 		return false;
 	}
+
+	// Create a synchronous worker and process jobs.
 	$worker = new \Soderlind\RedisQueue\Workers\Sync_Worker( $instance->get_queue_manager(), $instance->get_job_processor() );
 	return $worker->process_jobs( (array) $queue, $max_jobs );
 }

src/Contracts/Job_Result.php

@@ -1,14 +1,79 @@
 <?php
 namespace Soderlind\RedisQueue\Contracts;
 
+/**
+ * Job Result Interface.
+ * Defines the contract for job execution results.
+ * 
+ * Results track success/failure status, data, errors, and performance metrics.
+ * They must be serializable for storage in the database.
+ */
 interface Job_Result {
+	/**
+	 * Check if job execution was successful.
+	 * 
+	 * @return bool True if successful, false if failed.
+	 */
 	public function is_successful();
+
+	/**
+	 * Get result data.
+	 * Data returned by successful job execution.
+	 * 
+	 * @return mixed Result data.
+	 */
 	public function get_data();
+
+	/**
+	 * Get error message.
+	 * Returns error message if job failed.
+	 * 
+	 * @return string|null Error message or null if successful.
+	 */
 	public function get_error_message();
+
+	/**
+	 * Get error code.
+	 * Returns error code if job failed.
+	 * 
+	 * @return int|null Error code or null if successful.
+	 */
 	public function get_error_code();
+
+	/**
+	 * Get result metadata.
+	 * Additional contextual information about the result.
+	 * 
+	 * @return array Metadata.
+	 */
 	public function get_metadata();
+
+	/**
+	 * Get job execution time in seconds.
+	 * 
+	 * @return float|null Execution time or null if not measured.
+	 */
 	public function get_execution_time();
+
+	/**
+	 * Get peak memory usage in bytes.
+	 * 
+	 * @return int|null Memory usage or null if not measured.
+	 */
 	public function get_memory_usage();
+
+	/**
+	 * Convert result to array for serialization.
+	 * 
+	 * @return array Result data as array.
+	 */
 	public function to_array();
+
+	/**
+	 * Create result from array data.
+	 * 
+	 * @param array $data Result data array.
+	 * @return self Result instance.
+	 */
 	public static function from_array( $data );
 }

src/Contracts/Queue_Job.php

@@ -1,17 +1,103 @@
 <?php
 namespace Soderlind\RedisQueue\Contracts;
 
+/**
+ * Queue Job Interface.
+ * Defines the contract that all queue jobs must implement.
+ * 
+ * Jobs must be serializable for storage in Redis and the database.
+ * They must also handle execution, failures, and retry logic.
+ */
 interface Queue_Job {
+	/**
+	 * Get job type identifier.
+	 * 
+	 * @return string Job type.
+	 */
 	public function get_job_type();
+
+	/**
+	 * Get job payload data.
+	 * 
+	 * @return array Job payload.
+	 */
 	public function get_payload();
+
+	/**
+	 * Get job priority.
+	 * Lower values indicate higher priority.
+	 * 
+	 * @return int Priority value.
+	 */
 	public function get_priority();
+
+	/**
+	 * Get maximum retry attempts.
+	 * 
+	 * @return int Max retry attempts.
+	 */
 	public function get_retry_attempts();
+
+	/**
+	 * Get execution timeout in seconds.
+	 * 
+	 * @return int Timeout in seconds.
+	 */
 	public function get_timeout();
+
+	/**
+	 * Get queue name for this job.
+	 * 
+	 * @return string Queue name.
+	 */
 	public function get_queue_name();
-	public function execute(); // Must return Job_Result
+
+	/**
+	 * Execute the job.
+	 * Must return a Job_Result indicating success or failure.
+	 * 
+	 * @return Job_Result Job execution result.
+	 */
+	public function execute();
+
+	/**
+	 * Handle job failure.
+	 * Called when job fails to allow custom error handling and logging.
+	 * 
+	 * @param mixed $exception Exception or failure reason.
+	 * @param int   $attempt   Current attempt number.
+	 */
 	public function handle_failure( $exception, $attempt );
+
+	/**
+	 * Determine if job should be retried after failure.
+	 * 
+	 * @param mixed $exception Exception or failure reason.
+	 * @param int   $attempt   Current attempt number.
+	 * @return bool True if job should be retried.
+	 */
 	public function should_retry( $exception, $attempt );
+
+	/**
+	 * Get delay before retry in seconds.
+	 * 
+	 * @param int $attempt Attempt number.
+	 * @return int Delay in seconds.
+	 */
 	public function get_retry_delay( $attempt );
+
+	/**
+	 * Serialize job for storage.
+	 * 
+	 * @return array Serialized job data.
+	 */
 	public function serialize();
+
+	/**
+	 * Deserialize job from stored data.
+	 * 
+	 * @param array $data Serialized job data.
+	 * @return self Job instance.
+	 */
 	public static function deserialize( $data );
 }