Realtime

Subscribe to a collection

import com.bunbase.sdk.SubscribeOptions

data class Post(val title: String, val body: String)
val posts = client.collection("posts", Post::class.java)

val sub = client.realtime.subscribe<Post>(posts.channel) { event ->
    when (event.event) {
        RealtimeEventType.create -> println("New: ${event.record.title}")
        RealtimeEventType.update -> println("Updated: ${event.record.title}")
        RealtimeEventType.delete -> println("Deleted")
    }
}

// Unsubscribe when done (e.g., in onCleared)
sub.cancel()

Subscription is automatically cancelled when garbage-collected, but always call cancel() explicitly in lifecycle methods.

Subscribe to a single record

val sub = client.realtime.subscribe<Post>(posts.recordChannel("post_id")) { event ->
    println("Record changed: ${event.record}")
}

Filter by event type

val sub = client.realtime.subscribe<Post>(
    channel = posts.channel,
    options = SubscribeOptions(events = listOf(RealtimeEventType.create)),
) { event ->
    println("New post: ${event.record.title}")
}

Filter by field value

val sub = client.realtime.subscribe<Post>(
    channel = posts.channel,
    options = SubscribeOptions(filter = mapOf("status" to "published")),
) { event ->
    // Only events where post.status == "published"
}

Subscribe to current user’s records

val sub = client.realtime.subscribe<Post>(posts.mineChannel) { event ->
    // Only records owned by the authenticated user
}

Subscribe to multiple records by ID

val sub = client.realtime.subscribe<Post>(
    channel = posts.recordsChannel,
    options = SubscribeOptions(ids = listOf("id_1", "id_2", "id_3")),
) { event ->
    // events for any of the listed IDs
}

Ping

lifecycleScope.launch {
    try {
        client.realtime.ping()
        println("Connected")
    } catch (e: BunBaseError.Timeout) {
        println("No response")
    }
}

Presence (requires Redis in the server)

val userIds = client.realtime.presence("collection:chat")
println("Online: $userIds")

List active subscriptions

val channels = client.realtime.getSubscriptions()
println(channels)

Lifecycle management

class ChatViewModel : ViewModel() {
    private var sub: Subscription? = null

    fun startListening() {
        sub = client.realtime.subscribe<Message>(channel) { event ->
            // Handle message
        }
    }

    override fun onCleared() {
        sub?.cancel()
    }
}

Manual connect / disconnect

// Eagerly open the connection (auth events delivered immediately)
client.realtime.connect()

// Close and stop reconnecting
client.realtime.disconnect()

Auth revocation

When the server pushes a session_revoked or account_deleted event, the SDK automatically:

1. Clears tokens from memory and EncryptedSharedPreferences.
2. Emits null on auth.currentUser.
3. Closes the WebSocket.

No extra setup required.

Reconnect backoff

The SDK reconnects automatically on unexpected close with exponential backoff: 500 ms, 1 s, 2 s, … up to 30 s.