How to delete user from MU site when the user is removed from their site?

Question

When an Administrator for a sub site removes a user from their sub site, I am trying to not only remove the user, but also completely delete them from the entire MU site. I have tried this:

add_action( 'remove_user_from_blog', 'custom_remove_user', 10,4 );
function custom_remove_user( $user_id ) {
     wpmu_delete_user( $user_id );
}

but i am not able to get it to work - it is not actually deleting the user and it fact when creating the user it is not being assigned to the proper sub site.

If I input an actual number of an existing user, the function works properly.

Any other suggestions for how to handle this?

Answer 1

The function you are looking for is wpmu_delete_user($user->ID)

I wrote a small plugin to delete users across the whole network by role:

<?php
/**
 * Plugin Name: Regbox Delete multisite users
 * Plugin URI: http://www.regbox.se/delete-multisite-users
 * Description: Delete users by role across network
 * Version: 0.1
 * Author: Adam Rehal
 * Author URI: http://www.regbox.se
 * License: GPL2
 */
// Make admin menu item in Users

add_action('admin_menu', 'dmu_submenu_page');

function dmu_submenu_page() {
    add_submenu_page( 'users.php', 'Delete multisite users', 'Delete users', 'manage_options', 'delete-multisite-users', 'dmu_callback' );
}

function dmu_callback() {
    echo '<div class="wrap"><div id="icon-tools" class="icon32"></div>';
    echo '<h2>Delete multisite users</h2>';
    echo '<p>Delete users by role across network. This will delete all users with the selected role from the current site AND from the network</p>';
    echo '<p>Users with the same role on other sites will not be removed. You can also use the Count button to count the number of users with a specific role</p>';
    echo '</div>';

    // Get all roles
    global $wp_roles;
    $roles = $wp_roles->get_names();

    // Get all blogs
    $blog_list = get_blog_list( 0, 'all' ); ?>

    <form method="get" action="users.php?page=delete-multisite-users">
        <input type="hidden" name="page" value="delete-multisite-users">
        <input id="what-to-do" type="hidden" name="action" value="">

        <!--
        Select blog:
        <select name="blog">
        <?php
        foreach ($blog_list as $blog) { ?>
        <option value="<?php echo $blog['blog_id'];?>"><?php echo str_replace('/','',$blog['path']);?></option>
        <?php }//end foreach ?>
        </select><br>
        -->

        Select Role:
        <select name="role">
        <?php foreach($roles as $role_value => $role_name) { ?>
           <option value="<?php echo $role_value;?>"><?php echo $role_name;?></option>
        <?php }//end foreach ?>
        </select>
        <input class="button button-secondary" onClick="javascript:document.getElementById('what-to-do').value = 'delete';" type="submit" value="Delete">
        <input class="button button-primary" onClick="javascript:document.getElementById('what-to-do').value = 'count';" type="submit" value="Count">
    </form>
    <?php
    // Needed to make use of wp_delete_user()
    require_once( ABSPATH . '/wp-admin/includes/user.php' );
    $data = new WP_User_Query( array( 'role' => $_GET['role']) );
    $userList = $data->get_results();
    $deleted = 0;
    $counted = 0;
    if($_GET['action'] == 'delete'){
        if($_GET['role'] != 'administrator'){
            foreach ($userList as $u) {
                if(wpmu_delete_user( $u->ID )){ $deleted++; }
            }
            echo "<p>" . $deleted . " user(s) deleted</p>";
        }else {
            echo "<p>Admin cannot be deleted</p>";
        }
    }
    if($_GET['action'] == 'count'){
        foreach ($userList as $u) {
            $counted++;
        }
        echo "<p>" . $counted . " " . $_GET['role'] . " user(s) on current site</p>";
    }
}

Answer 2

If I input an actual number of an existing user, the function works properly.

The same user may exist on some other website on your MU farm. Try figuring out the problem from the error log. Is your admin also super admin?

File: /wp-admin/includes/ms.php

192: function wpmu_delete_user( $id ) {
...
206:    $_super_admins = get_super_admins();
207:    if ( in_array( $user->user_login, $_super_admins, true ) ) {
208:        return false;
209:    }

This may be the problem. Only super admins can remove the users.