1 package de.juplo.kafka.chat.backend.persistence;
3 import de.juplo.kafka.chat.backend.domain.Message;
4 import de.juplo.kafka.chat.backend.domain.MessageMutationException;
5 import de.juplo.kafka.chat.backend.domain.PersistenceStrategy;
6 import lombok.extern.slf4j.Slf4j;
7 import reactor.core.publisher.Flux;
8 import reactor.core.publisher.Mono;
10 import java.time.LocalDateTime;
11 import java.util.LinkedHashMap;
15 public class InMemoryPersistenceStrategy implements PersistenceStrategy
17 private final LinkedHashMap<Message.MessageKey, Message> messages;
20 public InMemoryPersistenceStrategy(LinkedHashMap<Message.MessageKey, Message> messages)
22 this.messages = messages;
27 public Mono<Message> persistMessage(
28 Message.MessageKey key,
29 LocalDateTime timestamp,
32 Message message = new Message(key, (long)messages.size(), timestamp, text);
34 Message existing = messages.get(key);
37 log.info("Message with key {} already exists; {}", key, existing);
38 if (!message.equals(existing))
39 throw new MessageMutationException(message, existing);
43 messages.put(key, message);
45 .fromSupplier(() -> message)
50 public Mono<Message> getMessage(Message.MessageKey key)
52 return Mono.fromSupplier(() -> messages.get(key));
56 public Flux<Message> getMessages(long first, long last)
58 return Flux.fromStream(messages
63 long serial = message.getSerialNumber();
64 return serial >= first && serial <= last;