A toe-dip into transients for Thierry

Get_Words.php

<?php


class Get_Words {

	public static $transient_name = 'awesome_words_compiled';
	public static $option_name = 'awesome_words_compiled';
	public static $repeater_name_left = 'awesome_words_repeater_left';
	public static $repeater_name_right = 'awesome_words_repeater_right';
	
	public static $repeater_subfield = 'words';

	public static $cpt = 'my_cpt';

	public function __construct() {
	}


	public function init() {

		add_action( 'save_post', [ $this, 'delete_transient' ] );
	}


	/*
	 * Easy to then use anywhere
	 *
	 * $words = Get_Words::get_words();
	 *
	 * Could call directly in your templates
	 * Can use it with wp_localize_script() to pass it to your JS
	 * ...
	 *
	 */
	public static function get_words() {
		$words = get_transient( self::$transient_name );

		// if the transient is ready, it's a single call to the DB! and
		// we can move along.
		// If not, then we need to regenerate it
		if ( empty( $words ) ) {
			$words = self::compile_words();
		}

		return $words;
	}


	/*
	 * Since this one is a bit longer, let's keep the get_words easier to read by splitting up
	 * the "compiling" routine
	 */
	public static function compile_words() {

		$words = [
			'left' => [],
			'right' => [],
		];
		
		
		


		// whatever logic you need to compile it all into a nice array that you'll re-use or pass to JS
		if ( function_exists( 'have_rows' ) && have_rows( self::$repeater_name_left ) ) {
			while ( have_rows( self::$repeater_name_left ) ) {
				the_row();

				$words['left'][] = get_sub_field( self::$repeater_subfield );

			}
		}
		
		// droite
		if ( function_exists( 'have_rows' ) && have_rows( self::$repeater_name_right ) ) {
			while ( have_rows( self::$repeater_name_right ) ) {
				the_row();

				$words['right'][] = get_sub_field( self::$repeater_subfield );

			}
		}

		set_transient( self::$transient_name, $words );

		return $words;

	}


	/*
	 * transients are, basically, options.
	 * They live in the options table
	 * The third param of set_transient() is expiry
	 * ..so, think of them like potentially-expiring options
	 *
	 * That being said, you have to think through the cases where
	 * your data becomes invalid... "WHEN" should they be refreshed?
	 *
	 * Most of the time, it's based on "Someone saved a post, our data might be invalid"
	 * ...so it's more likekely tied to a hook, probably
	 *
	 * For this example, I tied it to the save_post hook (in the init method above)
	 */
	public function delete_transient( $post_id, $post, $update ) {

		// Only set for post_type = our cpt
		if ( self::$cpt !== $post->post_type ) {
			return;
		}


		// oh. it IS the right saving screen for our CPT! Let's delete the transient.
		// We won't actually recreate it just yet... it might never be needed (although, doubtful)
		// We'll let the "get_words()" method call the compilation method, if needed
		delete_transient( self::$transient_name );
	}


}

$get_words = new Get_Words();
$get_words->init();