api/org.octavius.data.notification/PgChannelListener

PgChannelListener

Manages PostgreSQL LISTEN/UNLISTEN subscriptions on a dedicated database connection.

Each instance holds a single dedicated connection that lives for the duration of the listener's lifecycle. Use close (or kotlin.io.use) to release the connection when done.

Typical usage:

db.createChannelListener().use { listener ->
    listener.listen("orders", "notifications")
    listener.notifications()
        .collect { notification ->
            println("Received on ${notification.channel}: ${notification.payload}")
        }
}

Functions

abstract fun close()

listen

abstract fun listen(vararg channels: String): DataResult<Unit>

Subscribes to the given channels. Executes LISTEN for each channel.

notifications

abstract fun notifications(): Flow<PgNotification>

Returns a cold Flow of PgNotification objects received on subscribed channels.

unlisten

abstract fun unlisten(vararg channels: String): DataResult<Unit>

Unsubscribes from the given channels. Executes UNLISTEN for each channel.

unlistenAll

abstract fun unlistenAll(): DataResult<Unit>

Unsubscribes from all currently subscribed channels. Executes UNLISTEN *.