How to broadcast to a specific socketid or user?

[Mark Orosa]

is there a way to implement something like this:

socket.broadcast.to(id).emit('my message', msg);

or do I create rooms dynamically?

[lexxorlov]

Hello, It easy. Use "EventRoomInterface". You can set to $data some "user_id", so event will be:

    class CountEvent implements EventInterface, EventPubInterface, EventRoomInterface
    {
        ...

        protected $userId;

        /**
         * Socket.io room
         * @return string
         */
        public function room(): string
        {
            return 'user_id_' . $this->userId;
        }            
            
        /**
         * Emit client event
         * @param array $data
         * @return array
         */
        public function fire(array $data): array
        {
            $this->userId = $data['userId'];
            return [
                'count' => 10
            ];
        }

        ...

     }

Client side:

    var socket = io('localhost:1367/notifications');
    socket.emit('join', {room: 'user_id_<?= Yii::$app->user->getId()// For example id 10 ?>'});
    // Now you will receive data from user
    socket.on('update_notification_count', function(data){
        console.log(data)
    });

//Run broadcast to client. Only user with id 10 will receive count = 10

\yiicod\socketio\Broadcast::emit(CountEvent::name(), ['count' => 10, 'userId' => 10])

Any other user will not receive data.

[Mark Orosa]

This is great, thank you for that!