import de.juplo.kafka.chat.backend.domain.ChatRoom;
import de.juplo.kafka.chat.backend.domain.ChatHomeService;
+import de.juplo.kafka.chat.backend.domain.ShardingStrategy;
import lombok.extern.slf4j.Slf4j;
import reactor.core.publisher.Flux;
import reactor.core.publisher.Mono;
-import java.util.HashMap;
-import java.util.Map;
-import java.util.UUID;
+import java.util.*;
@Slf4j
public class InMemoryChatHomeService implements ChatHomeService<InMemoryChatRoomService>
{
+ private final ShardingStrategy shardingStrategy;
private final Map<UUID, ChatRoom>[] chatrooms;
- public InMemoryChatHomeService(int numShards, Flux<ChatRoom> chatroomFlux)
+ public InMemoryChatHomeService(
+ ShardingStrategy shardingStrategy,
+ int numShards,
+ int[] ownedShards,
+ Flux<ChatRoom> chatroomFlux)
{
log.debug("Creating InMemoryChatHomeService");
+ this.shardingStrategy = shardingStrategy;
this.chatrooms = new Map[numShards];
+ Set<Integer> owned = Arrays
+ .stream(ownedShards)
+ .collect(
+ () -> new HashSet<>(),
+ (set, i) -> set.add(i),
+ (a, b) -> a.addAll(b));
for (int shard = 0; shard < numShards; shard++)
- chatrooms[shard] = new HashMap<>();
+ {
+ chatrooms[shard] = owned.contains(shard)
+ ? new HashMap<>()
+ : null;
+ }
chatroomFlux
+ .filter(chatRoom ->
+ {
+ int shard = shardingStrategy.selectShard(chatRoom.getId());
+ if (owned.contains(shard))
+ {
+ return true;
+ }
+ else
+ {
+ log.info("Ignoring not owned chat-room {}", chatRoom);
+ return false;
+ }
+ })
.toStream()
- .forEach(chatroom -> chatrooms[chatroom.getShard()].put(chatroom.getId(), chatroom));
+ .forEach(chatRoom ->
+ {
+ getChatRoomMapFor(chatRoom).put(chatRoom.getId(), chatRoom);
+ });
}
@Override
public Mono<ChatRoom> putChatRoom(ChatRoom chatRoom)
{
- chatrooms[chatRoom.getShard()].put(chatRoom.getId(), chatRoom);
+ getChatRoomMapFor(chatRoom).put(chatRoom.getId(), chatRoom);
return Mono.just(chatRoom);
}
{
return Flux.fromStream(chatrooms[shard].values().stream());
}
+
+
+ private Map<UUID, ChatRoom> getChatRoomMapFor(ChatRoom chatRoom)
+ {
+ int shard = shardingStrategy.selectShard(chatRoom.getId());
+ return chatrooms[shard];
+ }
}