restrict_specific_posts_to_specific_users.php

<? php
/**
 * Restrict post access to specific user IDs or user Roles.
 *
 * You can add this recipe to your site by creating a custom plugin
 * or using the Code Snippets plugin available for free in the WordPress repository.
 * Read this companion article for step-by-step directions on either method.
 * https://www.paidmembershipspro.com/create-a-plugin-for-pmpro-customizations/
 */
/**
 * Restrict post access to specific email addresses, user IDs, or roles.
 */
function restrict_specific_posts_to_specific_users_or_emails( $hasaccess, $thepost, $theuser, $post_membership_levels ) {

	/* SETTINGS */

	// Set your post/page IDs here
	$posts_array = array( 40 );  // integers only

	// Set the user IDs that have exclusive access
	$allowed_user_ids = array( 275, 13, 274 );

	// Set email addresses allowed access
	$allowed_user_emails = array(
		'[email protected]',
		'[email protected]',
		'[email protected]',
	);

	// Set allowed roles
	$allowed_user_roles = array( 'editor', 'administrator' );

	/* END SETTINGS */

	$thepost_id = $thepost->ID;

	// First restrict access to these posts for everyone
	if ( in_array( $thepost_id, $posts_array ) ) {
		$hasaccess = false;

		// Grant access if user ID is allowed
		if ( in_array( $theuser->ID, $allowed_user_ids ) ) {
			return true;
		}

		// Grant access if email is in allowed list
		if ( in_array( strtolower( $theuser->user_email ), array_map( 'strtolower', $allowed_user_emails ) ) ) {
			return true;
		}

		// Grant access if role is allowed
		foreach ( $allowed_user_roles as $role ) {
			if ( in_array( $role, (array) $theuser->roles ) ) {
				return true;
			}
		}
	}

	return $hasaccess;
}
add_filter( 'pmpro_has_membership_access_filter', 'restrict_specific_posts_to_specific_users_or_emails', 10, 4 );