Define which Stripe webhook applications are permitted, then exclude any other webhook request coming through

pmpro-stripe-webhook-permitted-applications.php

<?php

/**
 * Define which Stripe webhook applications are permitted, then exclude any other webhook request coming through.
 *
 * This is expecially useful when you have multiple websites sharing the same Stripe account.
 * Then, you gonna see multiple webhook requests coming from different applications.
 * This snippet will allow you to filter out the ones you don't want to process.
 */

// Detect Stripe webhook requests coming from an unexpected application and disable them.
add_action( 'pmpro_stripe_webhook_event_received', function ( $pmpro_stripe_event ) {
	// Configuration.
	$enabled_stripe_applications = [
		'ca_FTUyoenpif1m9qd9a5kEEFVcKpmMQs5m',
	];

	if ( ! in_array( $pmpro_stripe_event->data->object->application, $enabled_stripe_applications ) ) {
		add_action( 'pmpro_stripe_webhook_before_exit', function () {
			global $logstr;

			$logstr .= "Request coming from a different application.";
		} );

		pmpro_stripeWebhookExit();
	}
} );