Dynamic Gutenberg WP Block RichText Component Rendering (until Gutenberg 4.5.1)

richtext-render.php

<?php

/**
 * help rendering the richText Component saved object
 * was needed when RichText saved as array. Since Gutenberg 4.5.1. RichText saves in string!
 *
 * no dynamic nice rendering provided https://github.com/WordPress/gutenberg/projects/14#card-11206239
 *
 * @since    x.x.x
 * @param $arr object from the JS RichText Component
 * @return string Rendered HTML
 */

function richtextRender($arr) {
	$out = '';

	if (is_array($arr)){
		foreach ($arr as $line){
			$out .= richtextRenderLoop($line);
		}
	} else {
		$out = richtextRenderLoop($arr);
	}
	
	return $out;
}

function richtextRenderLoop($lines) {
	$out = '';

	if (is_array($lines)){
		if (empty( $lines['props']['children'] ) ) {
			$out .= '<' . $lines['type'] . '/>';
		} else {
			// opening tag
			$out .= '<' . $lines['type'];
			if (!empty( $lines['props']['href'] )){
				$out .= ' href="'.$lines['props']['href'].'"';
			}
			if (!empty( $lines['props']['target'] )){
				$out .= ' target="'.$lines['props']['target'].'"';
			}
			$out .= '>';
			// nesting tag
			foreach ($lines['props']['children'] as $line) {
				$out .= richtextRenderLoop($line);
			}
			// closing tag
			$out .= '</' . $lines['type'] . '>';
		}
	} else {
		$out .= $lines;
	}
	return $out;
}