Update Bulk Content Masks

custom-functions.php

	add_action( 'init', 'insert_content_masks' );
	function insert_content_masks(){
		$array_of_mask_urls = array(
			'https://landing-page.com/page-1',
			'https://landing-page.com/page-2',
			'https://landing-page.com/page-3',
			// …
			'https://landing-page.com/page-xxx', 
		);

		if( current_user_can( 'administrator' ) ){
			$cm_args = array(
				'post_type'      => 'post',
				'posts_per_page' => -1,
			);

			$cm_query = new WP_Query( $cm_args );
			$count    = 0;

			if( $cm_query->have_posts() ){
				while( $cm_query->have_posts() ){
					$post_id = get_the_ID();

					$errors = array();

					// Set URL					
					if( ! update_post_meta( $post_id, 'content_mask_url', $array_of_mask_urls[$count]  ) );
						$errors[] = 'URL Set Failed on post '. $post_id;

					// Enable Content Mask
					if( ! update_post_meta( $post_id, 'content_mask_url', $array_of_mask_urls[$count]  ) );
						$errors[] = 'CM Enable Set Failed on post '. $post_id;

					if( empty( $errors ) ){
						$count++;
					} else {
						wp_die( 'Updating Failed on Post: '. $post_id );
					}
				}
				wp_reset_postdata();
			}
		}
	}