MailPoet Custom Trigger Example for WP Zapier (Without creating the user in WordPress)

mailpoet-custom-trigger-wp-zapier.php

<?php
/**
 * Add subscribers to multiple MailPoet lists when receiving data from Zapier with WP Zapier plugin.
 * i.e. Add users to MailPoet lists via Zapier when added to Google Sheets.
 * For full blog post visit - https://yoohooplugins.com/add-subscribers-mailpoet-zapier
 */
 
 function add_subscribers_to_mailpoet_zapier( $user ) {

	//If lists aren't passed through just bail.
	if ( empty( $_REQUEST['lists'] ) ) {
		return $user;
	}

	if ( class_exists(\MailPoet\API\API::class ) ) {
		$mailpoet_api = \MailPoet\API\API::MP('v1');
	
		$sub = array(
			'email' => sanitize_email( $_REQUEST['email'] ),
			// 'first_name' => sanitize_text_field( $_REQUEST['first_name'] ),
			// 'last_name' => sanitize_text_field( $_REQUEST['last_name'] ),
			// 'cf_my_field' => sanitize_text_field( $_REQUEST['my_field'] ) //Replace 'my_field' with your custom field name (optional).
		);

		// See if the user exists first.
		try {
			$subscriber = $mailpoet_api->getSubscriber( $sub['email'] );
		} catch ( \Throwable $th ) {
			// If the user doesn't exist, create them.
			$subscriber = $mailpoet_api->addSubscriber( $sub );
		}

		// Try add the user to lists.
		if ( $subscriber ) {

			$user_id = $subscriber['id'];
			$lists_id = explode( ',', $_REQUEST['lists'] );

			$lists = array();
			foreach( $lists_id as $key => $list_id ) {
				$lists[] = intval( $list_id );
			}
		
			// add users to the lists.
			try {
				$subscribe = $mailpoet_api->subscribeToLists( $user_id, $lists );
			} catch ( \Throwable $th ) {
				echo 'unable to add to lists - ' . $th;
			}
		}
	}
	
	return $user;
}
add_filter( 'wp_zapier_custom_webhook', 'add_subscribers_to_mailpoet_zapier', 10, 1 );