Plugin Active for Logged in Users only

This article by Terry Hale suggests that you can create a MU Plugin for this kind of functionality. The code looks like this:

/**
 * Whenever the 'active_plugins' option is loaded
 * Remove certain plugins from activation for non-logged in users.
 * 
 * @param Array $plugins
 *
 * @return Array $plugins
 */
function disable_logged_in_plugin( $plugins ) {
     
    // The 'option_active_plugins' hook occurs before any user information get generated,
    // so we need to require this file early to be able to check for logged in status
    require (ABSPATH . WPINC . '/pluggable.php');
 
    // If we are logged in, and NOT an admin...
    if ( is_user_logged_in() & ! is_admin() ) {
 
        // Use the plugin folder and main file name here.
        // Bloom is used here as an example
        $key = array_search( 'bloom/bloom.php' , $plugins );
 
        if ( false !== $key ) {
            // Remove the plugin reference, based on its key
            unset( $plugins[ $key ] );
        }
         
        // You can "deactive" other plugins here as well,
        //  using the code above as a template.
         
    }
	
    return $plugins;

}
add_filter( 'option_active_plugins', 'disable_logged_in_plugin' );

You would need to replace the following with your specific plugin:

$key = array_search( 'bloom/bloom.php' , $plugins );

Note that it’s the plugin directory name and the plugin load file, in most cases it will also be the plugin name but not always.

thank you, I will try this. It would also be helpful to know how to make a plugin active for specific users only. Is this possible?

You could use the same code above but inside the is_user_logged_in() conditional you could add another conditional checking against current_user_can( 'edit_users' ) for capabilities or you can grab the current user with $user = wp_get_current_user(); and check against $user->roles or more specifically $user->user_login.

I tried your initial code you posted and linked to, and it works great – thanks.

To make the plugin active only for a specific user, unfortunately my php isn’t good enough to work this out. I basically want to say:
If user:”John” is logged in then John then …..
(Otherwise….. All other users (logged or logged out) )

I’m sure Howdy would be along soon to help you, but since I’m here, I’ll jump in with an answer. Replace the conditional if line in the original code with this:

// If we are logged in, and NOT getting admin, & logged in user name is John...
    if ( is_user_logged_in() && ! is_admin() &&  'John' == wp_get_current_user()->user_login ) {

Then above the return line, replace the closing curly brace } with this:

} else {
    // place code here that applies to all other users logged in or not, or admin requests
}

The code could look something like this, though this code is entirely untested.

/**
 * Whenever the 'active_plugins' option is loaded
 * Remove certain plugins from activation for non-logged in users.
 * 
 * @param Array $plugins
 *
 * @return Array $plugins
 */
function disable_logged_in_plugin( $plugins ) {
     
    // The 'option_active_plugins' hook occurs before any user information get generated,
    // so we need to require this file early to be able to check for logged in status
    require (ABSPATH . WPINC . '/pluggable.php');
	
	$user = wp_get_current_user();
	$acceptable_users = array(	// List of username ( login names ) to enable the plugin for.
		'john_doe',
		'admin',
		'user8162',
	);

	// If we don't have a user, they're not logged in and we can return early
	// If we do have a user and they're not in our list, we can return early
	if(
		empty( $user ) || 
		( ! empty( $user ) && ! in_array( $user->user_login, $acceptable_users ) )
	) {

		// Use the plugin folder and main file name here.
        // Bloom is used here as an example
        $key = array_search( 'bloom/bloom.php' , $plugins );
 
        if ( false !== $key ) {
            // Remove the plugin reference, based on its key
            unset( $plugins[ $key ] );
        }

	}
    
	
    return $plugins;

}
add_filter( 'option_active_plugins', 'disable_logged_in_plugin' );

So if we don’t have a user to work with, disable the plugin. If we do have a user to work with but their login name is not in our acceptable list, disable the plugin. Otherwise, return plugins as normal.

Thanks bcworkz & Howdy_McGee
Both of these worked perfectly.

Thankyou!