refactor: Refined stream-definition in `StorageStrategy#write`
[demos/kafka/chat] / src / main / java / de / juplo / kafka / chat / backend / implementation / StorageStrategy.java
1 package de.juplo.kafka.chat.backend.implementation;
2
3 import de.juplo.kafka.chat.backend.domain.ChatHomeService;
4 import de.juplo.kafka.chat.backend.domain.ChatRoomInfo;
5 import de.juplo.kafka.chat.backend.domain.Message;
6 import org.slf4j.Logger;
7 import org.slf4j.LoggerFactory;
8 import reactor.core.publisher.Flux;
9 import reactor.core.publisher.Mono;
10
11 import java.util.UUID;
12
13
14 public interface StorageStrategy
15 {
16   Logger log = LoggerFactory.getLogger(StorageStrategy.class.getCanonicalName());
17
18   default Mono<Void> write(ChatHomeService chatHomeService)
19   {
20     return writeChatRoomInfo(chatHomeService.getChatRoomInfo())
21         .flatMap(chatRoomInfo -> writeChatRoomData(
22             chatRoomInfo.getId(),
23             chatHomeService
24                 .getChatRoomData(chatRoomInfo.getId())
25                 .flatMapMany(chatRoomData -> chatRoomData.getMessages())
26             )
27             .then()
28             .doOnSuccess(empty -> log.info("Stored {}", chatRoomInfo))
29             .doOnError(throwable -> log.error("Could not store {}: {}", chatRoomInfo, throwable)))
30         .then()
31         .doOnSuccess(empty -> log.info("Stored {}", chatHomeService))
32         .doOnError(throwable -> log.error("Could not store {}: {}", chatHomeService, throwable));
33   }
34
35   Flux<ChatRoomInfo> writeChatRoomInfo(Flux<ChatRoomInfo> chatRoomInfoFlux);
36   Flux<ChatRoomInfo> readChatRoomInfo();
37   Flux<Message> writeChatRoomData(UUID chatRoomId, Flux<Message> messageFlux);
38   Flux<Message> readChatRoomData(UUID chatRoomId);
39 }