Autogenerate Feature Flags (#2201)

* Autogenerate Feature Flags (Won't work until MinestomDataGen 1.21-rev2 is released with datagen changes.)

* Rewrite feature flag auto-generation, add example in demo.

* Update data gen

* Remove dead code and fix access modifier on FeatureFlagImpl

code-generators/src/main/java/net/minestom/codegen/Generators.java

@@ -37,6 +37,7 @@ public class Generators {
         generator.generate(resource("sounds.json"), "net.minestom.server.sound", "SoundEvent", "BuiltinSoundEvent", "SoundEvents");
         generator.generate(resource("custom_statistics.json"), "net.minestom.server.statistic", "StatisticType", "StatisticTypeImpl", "StatisticTypes");
         generator.generate(resource("attributes.json"), "net.minestom.server.entity.attribute", "Attribute", "AttributeImpl", "Attributes");
+        generator.generate(resource("feature_flags.json"), "net.minestom.server", "FeatureFlag", "FeatureFlagImpl", "FeatureFlags");
 
         // Dynamic registries
         generator.generateKeys(resource("chat_types.json"), "net.minestom.server.message", "ChatType", "ChatTypes");

demo/src/main/java/net/minestom/demo/PlayerInit.java

@@ -2,6 +2,7 @@ package net.minestom.demo;
 
 import net.kyori.adventure.sound.Sound;
 import net.kyori.adventure.text.Component;
+import net.minestom.server.FeatureFlag;
 import net.minestom.server.MinecraftServer;
 import net.minestom.server.advancements.FrameType;
 import net.minestom.server.advancements.notifications.Notification;
@@ -103,6 +104,10 @@ public class PlayerInit {
             .addListener(AsyncPlayerConfigurationEvent.class, event -> {
                 final Player player = event.getPlayer();
 
+                // Show off adding and removing feature flags
+                event.addFeatureFlag(FeatureFlag.BUNDLE);
+                event.removeFeatureFlag(FeatureFlag.TRADE_REBALANCE); // not enabled by default, just removed for demonstration
+
                 var instances = MinecraftServer.getInstanceManager().getInstances();
                 Instance instance = instances.stream().skip(new Random().nextInt(instances.size())).findFirst().orElse(null);
                 event.setSpawningInstance(instance);

gradle/libs.versions.toml

@@ -3,7 +3,7 @@ metadata.format.version = "1.1"
 [versions]
 
 # Important dependencies
-data = "1.21"
+data = "1.21-rv2"
 adventure = "4.17.0"
 jetbrainsAnnotations = "23.0.0"
 slf4j = "2.0.7"

src/autogenerated/java/net/minestom/server/FeatureFlags.java

@@ -0,0 +1,13 @@
+package net.minestom.server;
+
+/**
+ * Code autogenerated, do not edit!
+ */
+@SuppressWarnings("unused")
+interface FeatureFlags {
+    FeatureFlag BUNDLE = FeatureFlagImpl.get("minecraft:bundle");
+
+    FeatureFlag VANILLA = FeatureFlagImpl.get("minecraft:vanilla");
+
+    FeatureFlag TRADE_REBALANCE = FeatureFlagImpl.get("minecraft:trade_rebalance");
+}

src/main/java/net/minestom/server/FeatureFlag.java

@@ -0,0 +1,6 @@
+package net.minestom.server;
+
+import net.minestom.server.registry.StaticProtocolObject;
+
+public sealed interface FeatureFlag extends StaticProtocolObject, FeatureFlags permits FeatureFlagImpl {
+}

src/main/java/net/minestom/server/FeatureFlagImpl.java

@@ -0,0 +1,33 @@
+package net.minestom.server;
+
+import net.minestom.server.registry.Registry;
+import net.minestom.server.utils.NamespaceID;
+import org.jetbrains.annotations.NotNull;
+
+record FeatureFlagImpl(@NotNull Registry.FeatureFlagEntry registry) implements FeatureFlag {
+
+    private static final Registry.Container<FeatureFlagImpl> CONTAINER = Registry.createStaticContainer(Registry.Resource.FEATURE_FLAGS,
+            (namespace, properties) -> new FeatureFlagImpl(Registry.featureFlag(namespace, properties)));
+
+    static FeatureFlag get(@NotNull String namespace) {
+        return CONTAINER.get(namespace);
+    }
+
+    static FeatureFlag getSafe(@NotNull String namespace) {
+        return CONTAINER.getSafe(namespace);
+    }
+
+    static FeatureFlag getId(int id) {
+        return CONTAINER.getId(id);
+    }
+
+    @Override
+    public @NotNull NamespaceID namespace() {
+        return registry.namespace();
+    }
+
+    @Override
+    public int id() {
+        return registry.id();
+    }
+}

src/main/java/net/minestom/server/event/player/AsyncPlayerConfigurationEvent.java

@@ -2,12 +2,12 @@ package net.minestom.server.event.player;
 
 import it.unimi.dsi.fastutil.objects.ObjectArraySet;
 import it.unimi.dsi.fastutil.objects.ObjectSets;
+import net.minestom.server.FeatureFlag;
 import net.minestom.server.entity.Player;
 import net.minestom.server.event.trait.PlayerEvent;
 import net.minestom.server.instance.Instance;
 import net.minestom.server.network.packet.server.configuration.ResetChatPacket;
 import net.minestom.server.network.packet.server.configuration.UpdateEnabledFeaturesPacket;
-import net.minestom.server.utils.NamespaceID;
 import org.jetbrains.annotations.NotNull;
 import org.jetbrains.annotations.Nullable;
 
@@ -26,7 +26,7 @@ public class AsyncPlayerConfigurationEvent implements PlayerEvent {
     private final Player player;
     private final boolean isFirstConfig;
 
-    private final ObjectArraySet<NamespaceID> featureFlags = new ObjectArraySet<>();
+    private final ObjectArraySet<FeatureFlag> featureFlags = new ObjectArraySet<>();
     private boolean hardcore;
     private boolean clearChat;
     private boolean sendRegistryData;
@@ -36,7 +36,7 @@ public class AsyncPlayerConfigurationEvent implements PlayerEvent {
         this.player = player;
         this.isFirstConfig = isFirstConfig;
 
-        this.featureFlags.add(NamespaceID.from("minecraft:vanilla")); // Vanilla feature-set, without this you get nothing at all. Kinda wacky!
+        this.featureFlags.add(FeatureFlag.VANILLA); // Vanilla feature-set, without this you get nothing at all. Kinda wacky!
 
         this.hardcore = false;
         this.clearChat = false;
@@ -71,8 +71,9 @@ public class AsyncPlayerConfigurationEvent implements PlayerEvent {
      * @param feature A minecraft feature flag
      *
      * @see UpdateEnabledFeaturesPacket
+     * @see net.minestom.server.FeatureFlag
      */
-    public void addFeatureFlag(@NotNull NamespaceID feature) {
+    public void addFeatureFlag(@NotNull FeatureFlag feature) {
         this.featureFlags.add(feature);
     }
 
@@ -84,8 +85,9 @@ public class AsyncPlayerConfigurationEvent implements PlayerEvent {
      * @return if the feature specified existed prior to being removed
      *
      * @see UpdateEnabledFeaturesPacket
+     * @see net.minestom.server.FeatureFlag
      */
-    public boolean removeFeatureFlag(@NotNull NamespaceID feature) {
+    public boolean removeFeatureFlag(@NotNull FeatureFlag feature) {
         return this.featureFlags.remove(feature); // Should this have sanity checking to see if the feature was actually contained in the list?
     }
 
@@ -95,8 +97,9 @@ public class AsyncPlayerConfigurationEvent implements PlayerEvent {
      * @return An unmodifiable set of feature flags
      *
      * @see UpdateEnabledFeaturesPacket
+     * @see net.minestom.server.FeatureFlag
      */
-    public @NotNull Set<NamespaceID> getFeatureFlags() {
+    public @NotNull Set<FeatureFlag> getFeatureFlags() {
         return ObjectSets.unmodifiable(this.featureFlags);
     }
 

src/main/java/net/minestom/server/network/ConnectionManager.java

@@ -24,6 +24,7 @@ import net.minestom.server.network.packet.server.play.StartConfigurationPacket;
 import net.minestom.server.network.player.PlayerConnection;
 import net.minestom.server.network.player.PlayerSocketConnection;
 import net.minestom.server.network.plugin.LoginPluginMessageProcessor;
+import net.minestom.server.registry.StaticProtocolObject;
 import net.minestom.server.utils.StringUtils;
 import net.minestom.server.utils.async.AsyncUtils;
 import net.minestom.server.utils.debug.DebugUtils;
@@ -37,6 +38,7 @@ import org.jetbrains.annotations.Nullable;
 import java.util.*;
 import java.util.concurrent.*;
 import java.util.function.Function;
+import java.util.stream.Collectors;
 
 /**
  * Manages the connected clients.
@@ -278,7 +280,7 @@ public final class ConnectionManager {
             EventDispatcher.call(event);
             if (!player.isOnline()) return; // Player was kicked during config.
 
-            player.sendPacket(new UpdateEnabledFeaturesPacket(event.getFeatureFlags())); // send player features that were enabled or disabled during async config event
+            player.sendPacket(new UpdateEnabledFeaturesPacket(event.getFeatureFlags().stream().map(StaticProtocolObject::namespace).collect(Collectors.toSet()))); // send player features that were enabled or disabled during async config event
 
             final Instance spawningInstance = event.getSpawningInstance();
             Check.notNull(spawningInstance, "You need to specify a spawning instance in the AsyncPlayerConfigurationEvent");

src/main/java/net/minestom/server/registry/Registry.java

@@ -70,6 +70,11 @@ public final class Registry {
         return new EntityEntry(namespace, main, null);
     }
 
+    @ApiStatus.Internal
+    public static FeatureFlagEntry featureFlag(String namespace, @NotNull Properties main) {
+        return new FeatureFlagEntry(namespace, main, null);
+    }
+
     @ApiStatus.Internal
     public static PotionEffectEntry potionEffect(String namespace, @NotNull Properties main) {
         return new PotionEffectEntry(namespace, main, null);
@@ -207,6 +212,7 @@ public final class Registry {
         BLOCKS("blocks.json"),
         ITEMS("items.json"),
         ENTITIES("entities.json"),
+        FEATURE_FLAGS("feature_flags.json"),
         SOUNDS("sounds.json"),
         COMMAND_ARGUMENTS("command_arguments.json"),
         STATISTICS("custom_statistics.json"),
@@ -708,6 +714,15 @@ public final class Registry {
         }
     }
 
+    public record FeatureFlagEntry(NamespaceID namespace, int id, Properties custom) implements Entry {
+        public FeatureFlagEntry(String namespace, Properties main, Properties custom) {
+            this(NamespaceID.from(namespace),
+                    main.getInt("id"),
+                    null
+            );
+        }
+    }
+
     public record DamageTypeEntry(NamespaceID namespace, float exhaustion,
                                   String messageId,
                                   String scaling,