.

core-bukkit-api/build.gradle.kts

@@ -34,7 +34,10 @@ dependencies {
     testRuntimeOnly("org.junit.platform:junit-platform-launcher")
 
     api("org.spigotmc:spigot-api:1.21.11-R0.1-SNAPSHOT")
-    api("net.kyori:adventure-platform-bukkit:4.4.1")
+
+    // Source: https://mvnrepository.com/artifact/io.nats/jnats
+    implementation("io.nats:jnats:2.25.2")
+    api("io.nats:jnats:2.25.2")
 
     api("de.kentoj.scrow:kencommandapi-core:0.2")
     implementation("de.kentoj.scrow:kencommandapi-bukkit:0.2")

core-bukkit-api/src/main/java/de/kentoj/scrow/bukkit/ScrowAPI.java

@@ -4,6 +4,8 @@ import com.mongodb.reactivestreams.client.MongoDatabase;
 import de.kentoj.kencommandapi.BukkitKenCommandApi;
 import de.kentoj.scrow.bukkit.friends.FriendRequestService;
 import de.kentoj.scrow.bukkit.friends.FriendshipService;
+import de.kentoj.scrow.bukkit.message.NatsDocumentRepository;
+import io.nats.client.Connection;
 import lombok.AccessLevel;
 import lombok.Getter;
 import lombok.NoArgsConstructor;
@@ -26,6 +28,10 @@ public class ScrowAPI {
     private static FriendshipService friendshipService;
     @Getter
     private static FriendRequestService friendRequestService;
+    @Getter
+    private static Connection nats;
+    @Getter
+    private static NatsDocumentRepository natsRepository;
 
     @ApiStatus.Internal
     public static void setDatabase(@Nullable MongoDatabase database) {
@@ -56,5 +62,15 @@ public class ScrowAPI {
     public static void setFriendRequestService(FriendRequestService friendRequestService) {
         ScrowAPI.friendRequestService = friendRequestService;
     }
+
+    @ApiStatus.Internal
+    public static void setNats(Connection nats) {
+        ScrowAPI.nats = nats;
+    }
+
+    @ApiStatus.Internal
+    public static void setNatsRepository(NatsDocumentRepository natsRepository) {
+        ScrowAPI.natsRepository = natsRepository;
+    }
 }
 

core-bukkit-api/src/main/java/de/kentoj/scrow/bukkit/message/NatsDocumentRepository.java

@@ -0,0 +1,16 @@
+package de.kentoj.scrow.bukkit.message;
+
+import io.nats.client.Message;
+import io.nats.client.Subscription;
+import org.bson.Document;
+
+import java.util.function.Consumer;
+
+public interface NatsDocumentRepository {
+
+    void publish(String topic, Document document);
+
+    Subscription subscribe(String topic, Consumer<Document> document);
+
+    Message request(String topic, Document document);
+}

core-bukkit-impl/src/main/java/de/kentoj/scrow/bukkit/CoreImplPlugin.java

@@ -2,6 +2,9 @@ package de.kentoj.scrow.bukkit;
 
 import de.kentoj.scrow.bukkit.economy.CoinsCommand;
 import de.kentoj.scrow.bukkit.friends.command.FriendCommand;
+import io.nats.client.Message;
+import io.nats.client.Nats;
+import org.bson.Document;
 import org.bukkit.plugin.java.JavaPlugin;
 import reactor.core.publisher.Mono;
 
@@ -37,6 +40,16 @@ public class CoreImplPlugin extends JavaPlugin {
         }
     }
 
+    private void registerServer() {
+        ScrowAPI.getNatsRepository().publish("crown.status", new Document()
+                .append("state", "up"));
+        ScrowAPI.getNatsRepository().subscribe("crown.status", doc -> {
+            doc.
+        });
+        ScrowAPI.getNats().reqpublish("crown.status", new Document()
+                .append("state", "up").toJson());
+    }
+
     @Override
     public void onDisable() {
         ScrowAPISurface.destroyScrowAPI();

core-bukkit-impl/src/main/java/de/kentoj/scrow/bukkit/ScrowAPISurface.java

@@ -11,6 +11,7 @@ import de.kentoj.scrow.bukkit.friends.friendship.InMemoryFriendshipService;
 import de.kentoj.scrow.bukkit.friends.friendship.MongoFriendshipService;
 import de.kentoj.scrow.bukkit.friends.request.InMemoryFriendRequestService;
 import de.kentoj.scrow.bukkit.friends.request.MongoFriendRequestService;
+import io.nats.client.Nats;
 import lombok.AccessLevel;
 import lombok.NoArgsConstructor;
 import org.bson.UuidRepresentation;
@@ -21,6 +22,8 @@ import org.bukkit.plugin.Plugin;
 import org.jetbrains.annotations.Nullable;
 import reactor.core.scheduler.Schedulers;
 
+import java.io.IOException;
+
 @NoArgsConstructor(access = AccessLevel.PRIVATE)
 public class ScrowAPISurface {
 
@@ -31,6 +34,12 @@ public class ScrowAPISurface {
             Bukkit.getScheduler().runTask(plugin, cmd);
         }));
 
+        try {
+            ScrowAPI.setMessageBroker(Nats.connect());
+        } catch (IOException | InterruptedException e) {
+            throw new RuntimeException(e);
+        }
+
         if (enableDatabase) {
             var pojoCodecProvider = PojoCodecProvider.builder().automatic(true).build();
             var codecRegistry = CodecRegistries.fromRegistries(