juplo.de Git - demos/kafka/chat/blob - src/main/java/de/juplo/kafka/chat/backend/persistence/inmemory/InMemoryChatHomeService.java

   1 package de.juplo.kafka.chat.backend.persistence.inmemory;
   2
   3 import de.juplo.kafka.chat.backend.domain.ChatRoom;
   4 import lombok.extern.slf4j.Slf4j;
   5 import reactor.core.publisher.Flux;
   6 import reactor.core.publisher.Mono;
   7
   8 import java.util.*;
   9
  10
  11 @Slf4j
  12 public class InMemoryChatHomeService
  13 {
  14   private final Map<UUID, ChatRoom>[] chatrooms;
  15
  16
  17   public InMemoryChatHomeService(
  18       int numShards,
  19       int[] ownedShards,
  20       Flux<ChatRoom> chatroomFlux)
  21   {
  22     log.debug("Creating InMemoryChatHomeService");
  23     this.chatrooms = new Map[numShards];
  24     Set<Integer> owned = Arrays
  25         .stream(ownedShards)
  26         .collect(
  27             () -> new HashSet<>(),
  28             (set, i) -> set.add(i),
  29             (a, b) -> a.addAll(b));
  30     for (int shard = 0; shard < numShards; shard++)
  31     {
  32       chatrooms[shard] = owned.contains(shard)
  33           ? new HashMap<>()
  34           : null;
  35     }
  36     chatroomFlux
  37         .filter(chatRoom ->
  38         {
  39           if (owned.contains(chatRoom.getShard()))
  40           {
  41             return true;
  42           }
  43           else
  44           {
  45             log.info("Ignoring not owned chat-room {}", chatRoom);
  46             return false;
  47           }
  48         })
  49         .toStream()
  50         .forEach(chatroom -> chatrooms[chatroom.getShard()].put(chatroom.getId(), chatroom));
  51   }
  52
  53   public void putChatRoom(ChatRoom chatRoom)
  54   {
  55     chatrooms[chatRoom.getShard()].put(chatRoom.getId(), chatRoom);
  56   }
  57
  58   public Mono<ChatRoom> getChatRoom(int shard, UUID id)
  59   {
  60     return Mono.justOrEmpty(chatrooms[shard].get(id));
  61   }
  62
  63   public Flux<ChatRoom> getChatRooms(int shard)
  64   {
  65     return Flux.fromStream(chatrooms[shard].values().stream());
  66   }
  67 }