SetUser.kt

val token: String = "user jwt token"
val user = User("user_id").apply {
   extraData["name"] = "John"
   extraData["image"] = "https://server.com/profile/picture.jpg"
}

client.setUser(user, token, object : InitConnectionListener() {
   override fun onSuccess(data: ConnectionData) {
       // user has been connected successful
   }

   override fun onError(error: ChatError) {
       // An error has succeeded 
   }
})