Add datapack registration lifecycle event

patches/api/0477-Add-datapack-registration-lifecycle-event.patch

@@ -0,0 +1,211 @@
+From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
+From: Jake Potrebic <jake.m.potrebic@gmail.com>
+Date: Sun, 12 May 2024 17:30:54 -0700
+Subject: [PATCH] Add datapack registration lifecycle event
+
+
+diff --git a/src/main/java/io/papermc/paper/datapack/Datapack.java b/src/main/java/io/papermc/paper/datapack/Datapack.java
+index 7b2ab0be10a21e0496ad1d485ff8cb2c0b92a2cb..e6037cc5b79b5206e5da8d53c5009932e7c81c86 100644
+--- a/src/main/java/io/papermc/paper/datapack/Datapack.java
++++ b/src/main/java/io/papermc/paper/datapack/Datapack.java
+@@ -29,4 +29,10 @@ public interface Datapack {
+         COMPATIBLE,
+     }
+
++    /**
++     * Position of the pack in the load order.
++     */
++    enum Position {
++        TOP, BOTTOM
++    }
+ }
+diff --git a/src/main/java/io/papermc/paper/datapack/DatapackRegistrar.java b/src/main/java/io/papermc/paper/datapack/DatapackRegistrar.java
+new file mode 100644
+index 0000000000000000000000000000000000000000..099383a3649f53cd17b01769f562fae878c73579
+--- /dev/null
++++ b/src/main/java/io/papermc/paper/datapack/DatapackRegistrar.java
+@@ -0,0 +1,153 @@
++package io.papermc.paper.datapack;
++
++import io.papermc.paper.plugin.configuration.PluginMeta;
++import io.papermc.paper.plugin.lifecycle.event.registrar.Registrar;
++import java.io.IOException;
++import java.net.URI;
++import java.nio.file.Path;
++import java.util.function.Consumer;
++import net.kyori.adventure.text.Component;
++import org.checkerframework.checker.nullness.qual.NonNull;
++import org.jetbrains.annotations.ApiStatus;
++import org.jetbrains.annotations.Contract;
++
++/**
++ * The registrar for datapacks. The event for this registrar
++ * is called anytime the game tries to discover datapacks at any of the
++ * configured locations. This means that if a datapack should stay available to the server,
++ * it must always be discovered whenever this event fires.
++ * <p>An example of a plugin loading a datapack from within it's own jar is below</p>
++ * <pre>{@code
++ * public class YourPluginBootstrap implements PluginBootstrap {
++ *     @Override
++ *     public void bootstrap(BoostrapContext context) {
++ *         final LifecycleEventManager<BootstrapContext> manager = context.getLifecycleManager();
++ *         manager.registerEventHandler(LifecycleEvents.DATAPACK_DISCOVERY, event -> {
++ *             DatapackRegistrar registrar = event.registrar();
++ *             try {
++ *                 final URI uri = Objects.requireNonNull(
++ *                     YourPluginBootstrap.class.getResource("/pack")
++ *                 ).toURI();
++ *                 registrar.discoverPack(uri, "packId");
++ *             } catch (final URISyntaxException | IOException e) {
++ *                 throw new RuntimeException(e);
++ *             }
++ *         });
++ *     }
++ * }
++ * }</pre>
++ * @see io.papermc.paper.plugin.lifecycle.event.types.LifecycleEvents#DATAPACK_DISCOVERY
++ */
++@ApiStatus.NonExtendable
++@ApiStatus.Experimental
++public interface DatapackRegistrar extends Registrar {
++
++    /**
++     * Discovers a datapack at the specified {@link URI} with the id.
++     * <p>Symlinks obey the {@code allowed_symlinks.txt} in the server root directory.</p>
++     *
++     * @param uri the location of the pack
++     * @param id a unique id
++     * @throws IOException if any IO error occurs
++     */
++    default void discoverPack(final @NonNull URI uri, final @NonNull String id) throws IOException {
++        this.discoverPack(uri, id, c -> {});
++    }
++
++    /**
++     * Discovers a datapack at the specified {@link URI} with the id.
++     * <p>Symlinks obey the {@code allowed_symlinks.txt} in the server root directory.</p>
++     *
++     * @param uri the location of the pack
++     * @param id a unique id
++     * @param configurer a configurer for extra options
++     * @throws IOException if any IO error occurs
++     */
++    void discoverPack(@NonNull URI uri, @NonNull String id, @NonNull Consumer<Configurer> configurer) throws IOException;
++
++    /**
++     * Discovers a datapack at the specified {@link Path} with the id.
++     * <p>Symlinks obey the {@code allowed_symlinks.txt} in the server root directory.</p>
++     *
++     * @param path the location of the pack
++     * @param id a unique id
++     * @throws IOException if any IO error occurs
++     */
++    default void discoverPack(final @NonNull Path path, final @NonNull String id) throws IOException {
++        this.discoverPack(path, id, c -> {});
++    }
++
++    /**
++     * Discovers a datapack at the specified {@link Path} with the id.
++     * <p>Symlinks obey the {@code allowed_symlinks.txt} in the server root directory.</p>
++     *
++     * @param path the location of the pack
++     * @param id a unique id
++     * @param configurer a configurer for extra options
++     * @throws IOException if any IO error occurs
++     */
++    void discoverPack(@NonNull Path path, @NonNull String id, @NonNull Consumer<Configurer> configurer) throws IOException;
++
++    /**
++     * Discovers a datapack at the specified {@link URI} with the id.
++     * <p>Symlinks obey the {@code allowed_symlinks.txt} in the server root directory.</p>
++     *
++     * @param pluginMeta the plugin which will be the "owner" of this datapack
++     * @param uri the location of the pack
++     * @param id a unique id
++     * @param configurer a configurer for extra options
++     * @throws IOException if any IO error occurs
++     */
++    void discoverPack(@NonNull PluginMeta pluginMeta, @NonNull URI uri, @NonNull String id, @NonNull Consumer<Configurer> configurer) throws IOException;
++
++    /**
++     * Discovers a datapack at the specified {@link Path} with the id.
++     * <p>Symlinks obey the {@code allowed_symlinks.txt} in the server root directory.</p>
++     *
++     * @param pluginMeta the plugin which will be the "owner" of this datapack
++     * @param path the location of the pack
++     * @param id a unique id
++     * @param configurer a configurer for extra options
++     * @throws IOException if any IO error occurs
++     */
++    void discoverPack(@NonNull PluginMeta pluginMeta, @NonNull Path path, @NonNull String id, @NonNull Consumer<Configurer> configurer) throws IOException;
++
++    /**
++     * Configures additional, optional, details about a datapack.
++     */
++    @ApiStatus.NonExtendable
++    @ApiStatus.Experimental
++    interface Configurer {
++
++        /**
++         * Changes the title of the datapack from the default which
++         * is just the "id" in the {@code registerPack} methods.
++         *
++         * @param title the new title
++         * @return the configurer for chaining
++         */
++        @Contract(value = "_ -> this", mutates = "this")
++        @NonNull Configurer title(@NonNull Component title);
++
++        /**
++         * Sets if this pack is required. Defaults to false.
++         * A required pack cannot be disabled.
++         *
++         * @param required true to require the pack
++         * @return the configurer for chaining
++         */
++        @Contract(value = "_ -> this", mutates = "this")
++        @NonNull Configurer required(boolean required);
++
++        /**
++         * Configures the position in the
++         * load order of this datapack.
++         *
++         * @param fixed won't move around in the load order as packs are added/removed
++         * @param position try to insert at the top of the order or bottom
++         * @return the configurer for chaining
++         */
++        @Contract(value = "_, _ -> this", mutates = "this")
++        @NonNull Configurer position(boolean fixed, Datapack.@NonNull Position position);
++    }
++}
+diff --git a/src/main/java/io/papermc/paper/plugin/lifecycle/event/types/LifecycleEvents.java b/src/main/java/io/papermc/paper/plugin/lifecycle/event/types/LifecycleEvents.java
+index 1fab48593c567fe05b085ac6e12dc22556cf0b92..dcff07f8fe1627662726611602bd0f8213e39133 100644
+--- a/src/main/java/io/papermc/paper/plugin/lifecycle/event/types/LifecycleEvents.java
++++ b/src/main/java/io/papermc/paper/plugin/lifecycle/event/types/LifecycleEvents.java
+@@ -1,10 +1,12 @@
+ package io.papermc.paper.plugin.lifecycle.event.types;
+
+ import io.papermc.paper.command.brigadier.Commands;
++import io.papermc.paper.datapack.DatapackRegistrar;
+ import io.papermc.paper.plugin.bootstrap.BootstrapContext;
+ import io.papermc.paper.plugin.lifecycle.event.LifecycleEvent;
+ import io.papermc.paper.plugin.lifecycle.event.LifecycleEventManager;
+ import io.papermc.paper.plugin.lifecycle.event.LifecycleEventOwner;
++import io.papermc.paper.plugin.lifecycle.event.registrar.RegistrarEvent;
+ import io.papermc.paper.plugin.lifecycle.event.registrar.ReloadableRegistrarEvent;
+ import org.bukkit.plugin.Plugin;
+ import org.jetbrains.annotations.ApiStatus;
+@@ -24,6 +26,13 @@ public final class LifecycleEvents {
+      */
+     public static final LifecycleEventType.Prioritizable<LifecycleEventOwner, ReloadableRegistrarEvent<Commands>> COMMANDS = prioritized("commands", LifecycleEventOwner.class);
+
++    /**
++     * This event is for informing the server about any available datapacks from other sources such as inside a plugin's jar. You
++     * can register a handler for this event only in {@link io.papermc.paper.plugin.bootstrap.PluginBootstrap#bootstrap(BootstrapContext)}.
++     * @see DatapackRegistrar an example of a datapack being discovered
++     */
++    public static final LifecycleEventType.Prioritizable<BootstrapContext, RegistrarEvent<DatapackRegistrar>> DATAPACK_DISCOVERY = prioritized("datapack_discovery", BootstrapContext.class);
++
+     //<editor-fold desc="helper methods" defaultstate="collapsed">
+     @ApiStatus.Internal
+     private static <E extends LifecycleEvent> LifecycleEventType.Monitorable<Plugin, E> plugin(final String name) {