Hook for fail and successful login actions

Question

I need to log fail and successful login actions.

What hook is better to use for this?

Answer 1

There are a few different hooks you can use (from wp_signon):

• wp_authenticate (action)
• authenticate (filter)
• wp_login (action)

But you may do best to override the pluggable wp_authenticate (from wp-includes/pluggable.php):

if ( !function_exists('wp_authenticate') ) :
/**
 * Checks a user's login information and logs them in if it checks out.
 *
 * @since 2.5.0
 *
 * @param string $username User's username
 * @param string $password User's password
 * @return WP_Error|WP_User WP_User object if login successful, otherwise WP_Error object.
 */
function wp_authenticate($username, $password) {
    $username = sanitize_user($username);
    $password = trim($password);

    $user = apply_filters('authenticate', null, $username, $password);

    if ( $user == null ) {
        // TODO what should the error message be? (Or would these even happen?)
        // Only needed if all authentication handlers fail to return anything.
        $user = new WP_Error('authentication_failed', __('<strong>ERROR</strong>: Invalid username or incorrect password.'));
    }

    $ignore_codes = array('empty_username', 'empty_password');

    if (is_wp_error($user) && !in_array($user->get_error_code(), $ignore_codes) ) {
        do_action('wp_login_failed', $username);
    }

    return $user;
}
endif;

All you would need to do is define your own wp_authenticate mimicking the actions and adding a few lines to do your logging. That is assuming you don't already have a function that is overriding it.

And as you can see right in the above code, you could use:

• wp_login_failed (action)

Answer 2

You can use action wp_login

Here is the code example

function after_login( $user_login, $user) {
    echo "<br/>Username: $user_login";
    echo "<br/>user obj: "; print_r($user);
}
add_action('wp_login', 'after_login', 10, 2);