Notifications are used to inform one or a given set of users about a specific event in your network as the liking of a post or mentioning of a user over multiple channels (e.g. web and mail).

Custom notification classes are derived from humhub\modules\notification\components\BaseNotification. A BaseNotification usually is assigned with an $originator user instance and a $source instance, which connects the Notification with a Content or any other kind of yii\db\ActiveRecord.

A Notification can be sent to a user by calling the send() or sendBulk() function. This will persist an humhub\modules\notification\models\Notification instance for each user send out a notification to all allowed NotificationTargets.

Note: Unlike Activities which are targeted for multiple users e.g. all Users of a Space, a Notification Model instance is always related to a single user.

Examples for core notifications are:

Custom Notifications

Notification Class

Custom Notifications are derived from BaseNotification and should reside in the notifications subfolder of your module's root directory.

The notification class at least has to overwrite the $moduleId variable with the id of your module and the.


namespace johndoe\example\notifications;

use humhub\modules\notification\components\BaseNotification;

 * Notifies a user about something happend
class SomethingHappend extends BaseNotification
    // Module Id (required)
    public $moduleId = "example";

    // Viewname (required)
    public $viewName = "somethingHappend";

Notification View

By default, the view of a notification should be located inside the subfolder notifications/views. The view of the example above should therefore be located in /modules/examples/notifications/views/somethingHappened.php.


use yii\helpers\Html;

echo Yii::t('SomethingHappend.views_notifications_somethingHappened', "%someUser% did something cool.", [
    '%someUser%' => '<strong>' . Html::encode($originator->displayName) . '</strong>'

Info: If you require a different notification view for mails, you have to add an extra view file to a subfolder notifications/views/mail.

Send Notifications

After an event was triggered, you'll have to instantiate your custom BaseNotification and call its send or sendBulk function which will instantiate and persist a humhub\modules\notification\models\Notification instance for each user you want to notify.

A notification can optionally be assigned with a $source model instance (e.g. a post or comment related to the notification) which has to be derived from yii\db\ActiveRecord.

// Sending to a single user

// Sending to multiple users

Info: The send and sendBulk will create and persist a humhub\modules\notification\models\Notification instance for each user.

Tip: Notifications are often created and sent within the afterSave hook of the related source instance. This should be prefered over the instantiation within a controller.

Note: Notifications are only sent to a specific NotificationTarget depending on the user's account settings.