Server Events

Being able to listen to events is a fundamental feature. Kursive uses Arcade's event system and is provided through context.events. All server events live under net.casual.arcade.events.server and implement ServerSideEvent.

While typically fabric mods use events provided by fabric api for example: ServerTickEvents.START_SERVER_TICK, these should be avoided as registered listeners here are permanent and won't be cleaned up when your script stops.

Registering a Listener

Arcade provides a register extension function that allows you register an event listener based on the type parameter provided. In the below example we send a "Welcome!" message to the player whenever they join the server:

// This extension function is required
import net.casual.arcade.events.utils.register

suspend fun main(server: MinecraftServer, context: ServerScriptContext) {
    context.events.register<PlayerJoinEvent> { event ->
        event.player.sendSystemMessage(Component.literal("Welcome, ${event.player.username}!"))
    }
    awaitCancellation()
}

Remember to keep the script alive with awaitCancellation(); if main returns the script stops and your listener goes with it.

To find a full list of listen-able events you can see all implementors of the ServerSideEvent interface in IntelliJ.

For full details about how the event system works you can read arcade's documentation.

More Examples

Many events extend CancellableEvent, cancelling them stops the thing from happening at all. Here we stop players from mining spawners:

context.events.register<PlayerBlockMinedEvent> { event ->
    if (event.state.isOf(Blocks.SPAWNER)) {
        event.cancel()
    }
}

Some cancellable events carry a result. For example, PlayerJoinEvent, cancelling it with a component kicks the player with that message:

context.events.register<PlayerJoinEvent> { event ->
    if (event.player.username == "Herobrine") {
        event.cancel(Component.literal("You are not welcome here"))
    }
}

Missing Events

While Arcade does have a quite a lot of available ServerSideEvents, if there's an event that you'd like to be implemented either make an issue report on the GitHub or send a message on my discord.