refactor: Pulled business-logic into class `ShardedChatHome`

[demos/kafka/chat] / src / main / java / de / juplo / kafka / chat / backend / domain / ShardedChatHome.java

diff --git a/src/main/java/de/juplo/kafka/chat/backend/domain/ShardedChatHome.java b/src/main/java/de/juplo/kafka/chat/backend/domain/ShardedChatHome.java
new file mode 100644 (file)
index 0000000..ffa7860
--- /dev/null
+++ b/src/main/java/de/juplo/kafka/chat/backend/domain/ShardedChatHome.java
@@ -0,0 +1,42 @@
+package de.juplo.kafka.chat.backend.domain;
+
+import lombok.RequiredArgsConstructor;
+import reactor.core.publisher.Flux;
+import reactor.core.publisher.Mono;
+
+import java.util.UUID;
+
+
+@RequiredArgsConstructor
+public class ShardedChatHome implements ChatHome
+{
+  private final ChatHome[] chatHomes;
+  private final ShardingStrategy selectionStrategy;
+
+
+  @Override
+  public Mono<ChatRoom> putChatRoom(ChatRoom chatRoom)
+  {
+    return chatHomes[selectShard(chatRoom.getId())].putChatRoom(chatRoom);
+  }
+
+  @Override
+  public Mono<ChatRoom> getChatRoom(UUID id)
+  {
+    return chatHomes[selectShard(id)].getChatRoom(id);
+  }
+
+  @Override
+  public Flux<ChatRoom> getChatRooms()
+  {
+    return Flux
+        .fromArray(chatHomes)
+        .flatMap(chatHome -> chatHome.getChatRooms());
+  }
+
+
+  private int selectShard(UUID chatroomId)
+  {
+    return selectionStrategy.selectShard(chatroomId);
+  }
+}