package de.juplo.kafka.chat.backend.api;
import de.juplo.kafka.chat.backend.domain.ChatHome;
-import de.juplo.kafka.chat.backend.domain.Chatroom;
+import de.juplo.kafka.chat.backend.domain.ChatRoom;
+import de.juplo.kafka.chat.backend.domain.ChatRoomFactory;
import de.juplo.kafka.chat.backend.persistence.StorageStrategy;
import lombok.RequiredArgsConstructor;
-import org.springframework.http.MediaType;
import org.springframework.http.codec.ServerSentEvent;
import org.springframework.web.bind.annotation.*;
import reactor.core.publisher.Flux;
import reactor.core.publisher.Mono;
-import java.time.Clock;
-import java.time.LocalDateTime;
-import java.util.Optional;
import java.util.UUID;
-import java.util.stream.Stream;
@RestController
@RequiredArgsConstructor
public class ChatBackendController
{
- private final ChatHome chatHome;
- private final Clock clock;
+ private final ChatHome[] chatHomes;
+ private final ShardingStrategy selectionStrategy;
+ private final ChatRoomFactory factory;
private final StorageStrategy storageStrategy;
@PostMapping("create")
- public ChatroomTo create(@RequestBody String name)
+ public Mono<ChatRoomTo> create(@RequestBody String name)
{
- return ChatroomTo.from(chatHome.createChatroom(name));
+ UUID chatRoomId = UUID.randomUUID();
+ return factory
+ .createChatRoom(chatRoomId, name)
+ .flatMap(chatRoom -> chatHomes[chatRoom.getShard()].putChatRoom(chatRoom))
+ .map(ChatRoomTo::from);
}
@GetMapping("list")
- public Stream<ChatroomTo> list()
+ public Flux<ChatRoomTo> list()
{
- return chatHome.list().map(chatroom -> ChatroomTo.from(chatroom));
+ return Flux
+ .fromArray(chatHomes)
+ .flatMap(chatHome -> chatHome.getChatRooms())
+ .map(chatroom -> ChatRoomTo.from(chatroom));
}
- @GetMapping("list/{chatroomId}")
+ @GetMapping("{chatroomId}/list")
public Flux<MessageTo> list(@PathVariable UUID chatroomId)
{
- return chatHome
- .getChatroom(chatroomId)
- .map(chatroom -> chatroom
+ return chatHomes[selectShard(chatroomId)]
+ .getChatRoom(chatroomId)
+ .flatMapMany(chatroom -> chatroom
.getMessages()
- .map(MessageTo::from))
- .get();
+ .map(MessageTo::from));
}
- @GetMapping("get/{chatroomId}")
- public Optional<ChatroomTo> get(@PathVariable UUID chatroomId)
+ @GetMapping("{chatroomId}")
+ public Mono<ChatRoomTo> get(@PathVariable UUID chatroomId)
{
- return chatHome.getChatroom(chatroomId).map(chatroom -> ChatroomTo.from(chatroom));
+ return chatHomes[selectShard(chatroomId)]
+ .getChatRoom(chatroomId)
+ .map(chatroom -> ChatRoomTo.from(chatroom));
}
- @PutMapping("put/{chatroomId}/{username}/{messageId}")
+ @PutMapping("{chatroomId}/{username}/{messageId}")
public Mono<MessageTo> put(
@PathVariable UUID chatroomId,
@PathVariable String username,
@RequestBody String text)
{
return
- chatHome
- .getChatroom(chatroomId)
- .map(chatroom -> put(chatroom, username, messageId, text))
- .orElseThrow(() -> new UnknownChatroomException(chatroomId));
+ chatHomes[selectShard(chatroomId)]
+ .getChatRoom(chatroomId)
+ .flatMap(chatroom -> put(chatroom, username, messageId, text));
}
public Mono<MessageTo> put(
- Chatroom chatroom,
+ ChatRoom chatroom,
String username,
Long messageId,
String text)
chatroom
.addMessage(
messageId,
- LocalDateTime.now(clock),
username,
text)
- .switchIfEmpty(chatroom.getMessage(username, messageId))
.map(message -> MessageTo.from(message));
}
- @GetMapping("get/{chatroomId}/{username}/{messageId}")
+ @GetMapping("{chatroomId}/{username}/{messageId}")
public Mono<MessageTo> get(
@PathVariable UUID chatroomId,
@PathVariable String username,
@PathVariable Long messageId)
{
return
- chatHome
- .getChatroom(chatroomId)
- .map(chatroom -> get(chatroom, username, messageId))
- .orElseThrow(() -> new UnknownChatroomException(chatroomId));
+ chatHomes[selectShard(chatroomId)]
+ .getChatRoom(chatroomId)
+ .flatMap(chatroom -> get(chatroom, username, messageId));
}
private Mono<MessageTo> get(
- Chatroom chatroom,
+ ChatRoom chatroom,
String username,
Long messageId)
{
.map(message -> MessageTo.from(message));
}
- @GetMapping(path = "listen/{chatroomId}")
+ @GetMapping(path = "{chatroomId}/listen")
public Flux<ServerSentEvent<MessageTo>> listen(@PathVariable UUID chatroomId)
{
- return chatHome
- .getChatroom(chatroomId)
- .map(chatroom -> listen(chatroom))
- .orElseThrow(() -> new UnknownChatroomException(chatroomId));
+ return chatHomes[selectShard(chatroomId)]
+ .getChatRoom(chatroomId)
+ .flatMapMany(chatroom -> listen(chatroom));
}
- private Flux<ServerSentEvent<MessageTo>> listen(Chatroom chatroom)
+ private Flux<ServerSentEvent<MessageTo>> listen(ChatRoom chatroom)
{
return chatroom
.listen()
@PostMapping("/store")
public void store()
{
- storageStrategy.writeChatrooms(Flux.fromStream(chatHome.list()));
+ for (int shard = 0; shard < chatHomes.length; shard++)
+ storageStrategy.write(chatHomes[shard].getChatRooms());
+ }
+
+ private int selectShard(UUID chatroomId)
+ {
+ return selectionStrategy.selectShard(chatroomId);
}
}