WordPress Transients - Helper Class - for handling WordPress Transients and caching data and keeping things simple as they should

WordPress Transients - Helper Class.php

<?php

/**
  * WordPress Transients - Helper Class
  * 
  * Makes it easier to store transients and call them and all in like 4 lines of code
  * Helps you save large amounts of data (arrays) without the confusing proccess of
  * chunking data into batches, and joining later upon getting all the data and also
  * deleting all of these batches correctly. This class does it all for you.
  *
  * @author Samuel Elh <samelh.com/contact>
  *
  * @example
  * // Getting all messages from DB
  * $s = microtime(1); // recording start time
  *	$data = se_transients::get( "messages", function(){
  *		global $wpdb;
  *		$table = $wpdb->prefix . 'bbp_messages';
  *		return $wpdb->get_results( "SELECT * FROM $table" );
  *	}, DAY_IN_SECONDS * 30 );
  *
  *	echo sprintf( "Query processed in %s ms", microtime(1) - $s );
  *	echo var_dump( $data );
  *
  * // if data was not cached before or transients exist but timed out, the callback
  * in param 2 will be called and it should return the data to cache then it will cache
  * these data and serve them upon later requests.
  *
  * @example
  * This example lets you use more functions
  * $s = microtime(1); // recording start time
  * $transients = new se_transients;
  *
  *	if ( false === $mydata = $transients::get( "messages" ) ) {
  *		global $wpdb;
  *		$table = $wpdb->prefix . 'bbp_messages';
  *		$mydata = $wpdb->get_results( "SELECT * FROM $table" );
  *		$transients::set( $mydata, DAY_IN_SECONDS, "messages" );
  *		echo "Data extracted from DB <br/>";
  *	}
  *
  *	echo var_dump( $mydata );
  *
  *	echo sprintf( "Query processed in %s ms", microtime(1) - $s );
  *
  * @example
  * purge and delete cache
  * se_transients::delete( "messages" ); // takes 1 param, the cache key
  */

class se_transients
{

	protected static $instance;
	public $per_item
	     , $is_object
	     , $batches
	     , $timeout
	     , $key;

	function __construct() {
		$this->per_item = 200;
		$this->is_object = $this->batches = null;
	}
	
	static function set( $data, $timeout, $key, $per_item = null ) {
		$class = null == self::$instance ? new self : self::$instance;
		return $class->_set( $data, $timeout, $key, $per_item );
	}

	static function get( $key, $callback = null, $timeout = null, $per_item = null ) {
		$class = null == self::$instance ? new self : self::$instance;
		return $class->_get( $key, $callback, $timeout, $per_item );
	}

	static function delete( $key ) {
		$class = null == self::$instance ? new self : self::$instance;
		return $class->_delete( $key );
	}

	function _set( $data, $timeout, $key, $per_item = null ) {

		$this->timeout = $timeout;
		$this->key = $key;

		if ( $per_item ) {
			$this->per_item = (int) $per_item;
		}

		$data = $this->chunks( $data );

		if ( $this->batches ) {

			foreach ( $data as $i => $portion ) {
				$key = sprintf( "%s_%d", $this->key, $i );
				set_transient("se_transients__{$key}", $portion, $this->timeout);
			}

			update_option( "se_transients_{$this->key}_length", count($data) );

		} else {
			set_transient("se_transients__{$this->key}", $data, $this->timeout);
		}

		if ( $this->is_object ) {
			update_option( "se_transients_is_object_{$this->key}", true );			
		}

		return true;
	}

	function _get( $key, $callback = null, $timeout = null, $per_item = null ) {

		$this->key = $key;

		if ( $timeout ) {
			$this->timeout = (int) $timeout;
		}

		if ( false !== $batches = (int) get_option( "se_transients_{$this->key}_length" ) ) {
			$this->batches = $batches;
		}

		if ( false !== $is_object = get_option( "se_transients_is_object_{$this->key}" ) ) {
			$this->is_object = true;
		}

		if ( ! $this->batches ) {
			$data = get_transient( "se_transients__{$this->key}" );
		} else {

			$data = array();
			$last_key = 0;

			for ( $i=0; $i < $this->batches; $i++ ) {
				$portion = get_transient( "se_transients__{$key}_{$i}" );

				if ( is_array($portion) ) {
					
					if ( !is_array( $portion ) ) {
						$data[$last_key] = $portion;
						$last_key++;
					} else {
						
						foreach ( $portion as $item ) {
							$data[$last_key] = $item;
							$last_key++;
						}

					}

				}
			}

		}

		if ( $this->is_object ) {
			$data = (object) $data;
		}

		if ( false === $data && !empty( $callback ) && is_callable( $callback ) ) {
			$data = call_user_func( $callback );
			$this->_set( $data, $this->timeout, $this->key, $per_item );
		}

		return $data;

	}

	function _delete( $key ) {

		$this->key = $key;

		if ( false !== $batches = (int) get_option( "se_transients_{$this->key}_length" ) ) {
			$this->batches = $batches;
			delete_option( "se_transients_{$this->key}_length" );
		}

		delete_option( "se_transients_is_object_{$this->key}" );

		if ( ! $this->batches ) {
			delete_transient( "se_transients__{$this->key}" );
		} else {

			for ( $i=0; $i < $this->batches; $i++ ) {
				delete_transient( "se_transients__{$key}_{$i}" );
			}

		}

	}

	function chunks( $data ) {

		$original_data = $data;

		if ( is_object( $data ) ) {
			$data = (array) $data;
			$this->is_object = true;
		}

		else if ( !is_array( $data ) ) {
			return $data; // only array|object types are processed
		}

		$chunks = array_chunk($data, $this->per_item);
		
		if ( count( $chunks ) < 2 ) {
			return $original_data; // no chunks required
		}

		$this->batches = true;
		return $chunks;

	}


}