package de.juplo.kafka.chat.backend.implementation.kafka;
-import de.juplo.kafka.chat.backend.domain.ChatRoomData;
import de.juplo.kafka.chat.backend.domain.ChatRoomInfo;
-import de.juplo.kafka.chat.backend.domain.Message;
-import de.juplo.kafka.chat.backend.domain.exceptions.LoadInProgressException;
-import de.juplo.kafka.chat.backend.domain.exceptions.ShardNotOwnedException;
import de.juplo.kafka.chat.backend.implementation.kafka.messages.AbstractMessageTo;
-import de.juplo.kafka.chat.backend.implementation.kafka.messages.data.CommandCreateChatRoomTo;
-import de.juplo.kafka.chat.backend.implementation.kafka.messages.data.EventChatMessageReceivedTo;
import de.juplo.kafka.chat.backend.implementation.kafka.messages.info.EventChatRoomCreated;
import lombok.extern.slf4j.Slf4j;
import org.apache.kafka.clients.consumer.Consumer;
import org.apache.kafka.clients.consumer.ConsumerRecords;
import org.apache.kafka.clients.producer.Producer;
import org.apache.kafka.clients.producer.ProducerRecord;
-import org.apache.kafka.common.TopicPartition;
import org.apache.kafka.common.errors.WakeupException;
import reactor.core.publisher.Flux;
import reactor.core.publisher.Mono;
private final String topic;
private final Producer<String, AbstractMessageTo> producer;
private final Consumer<String, AbstractMessageTo> consumer;
+ private final int numShards;
+ private final long[] startOffset;
+ private final long[] currentOffset;
private final Map<UUID, ChatRoomInfo> chatRoomInfo;
private boolean running;
this.consumer = infoChannelConsumer;
this.producer = producer;
this.chatRoomInfo = new HashMap<>();
+
+ this.numShards = consumer
+ .partitionsFor(topic)
+ .size();
+ this.startOffset = new long[numShards];
+ this.currentOffset = new long[numShards];
+ IntStream
+ .range(0, numShards)
+ .forEach(partition -> this.currentOffset[partition] = -1l);
+ consumer
+ .endOffsets(consumer.assignment())
+ .entrySet()
+ .stream()
+ .forEach(entry -> this.startOffset[entry.getKey().partition()] = entry.getValue());
}
+ Mono<Boolean> loadInProgress()
+ {
+ return Mono
+ .fromSupplier(() -> IntStream
+ .range(0, numShards)
+ .anyMatch(partition -> currentOffset[partition] < startOffset[partition]));
+ }
Mono<ChatRoomInfo> sendChatRoomCreatedEvent(
UUID chatRoomId,
- String name)
+ String name,
+ int shard)
{
- EventChatRoomCreated to = EventChatRoomCreated.of(name);
+ EventChatRoomCreated to = EventChatRoomCreated.of(chatRoomId, name, shard);
return Mono.create(sink ->
{
ProducerRecord<String, AbstractMessageTo> record =
new ProducerRecord<>(
- topic<,
- chatRoomId.toString(),
+ topic,
+ Integer.toString(shard),
to);
producer.send(record, ((metadata, exception) ->
{
if (metadata != null)
{
- log.info("Successfully send chreate-request for chat room: {}", to);
+ log.info("Successfully sent chreate-request for chat room: {}", to);
ChatRoomInfo chatRoomInfo = new ChatRoomInfo(chatRoomId, name, record.partition());
createChatRoom(chatRoomInfo);
sink.success(chatRoomInfo);
{
try
{
- ConsumerRecords<String, AbstractMessageTo> records = consumer.poll(Duration.ofMinutes(5));
- log.info("Fetched {} messages", records.count());
-
- if (loadInProgress)
- {
- loadChatRoom(records);
-
- if (isLoadingCompleted())
- {
- log.info("Loading of messages completed! Pausing all owned partitions...");
- pauseAllOwnedPartions();
- log.info("Resuming normal operations...");
- loadInProgress = false;
- }
- }
- else
- {
- if (!records.isEmpty())
- {
- throw new IllegalStateException("All owned partitions should be paused, when no load is in progress!");
- }
- }
+ ConsumerRecords<String, AbstractMessageTo> records = consumer.poll(Duration.ofMinutes(1));
+ log.debug("Fetched {} messages", records.count());
+ handleMessages(records);
}
catch (WakeupException e)
{
log.info("Exiting normally");
}
- private void loadChatRoom(ConsumerRecords<String, AbstractMessageTo> records)
+ private void handleMessages(ConsumerRecords<String, AbstractMessageTo> records)
{
for (ConsumerRecord<String, AbstractMessageTo> record : records)
{
- UUID chatRoomId = UUID.fromString(record.key());
-
switch (record.value().getType())
{
case EVENT_CHATROOM_CREATED:
- createChatRoom(
- chatRoomId,
- (CommandCreateChatRoomTo) record.value(),
- record.partition());
- break;
-
- case EVENT_CHATMESSAGE_RECEIVED:
- Instant instant = Instant.ofEpochSecond(record.timestamp());
- LocalDateTime timestamp = LocalDateTime.ofInstant(instant, zoneId);
- loadChatMessage(
- chatRoomId,
- timestamp,
- record.offset(),
- (EventChatMessageReceivedTo) record.value(),
- record.partition());
+ EventChatRoomCreated eventChatRoomCreated =
+ (EventChatRoomCreated) record.value();
+ createChatRoom(eventChatRoomCreated.toChatRoomInfo());
break;
default:
log.debug(
- "Ignoring message for chat-room {} with offset {}: {}",
- chatRoomId,
+ "Ignoring message for key={} with offset={}: {}",
+ record.key(),
record.offset(),
record.value());
}
- nextOffset[record.partition()] = record.offset() + 1;
+ startOffset[record.partition()] = record.offset() + 1;
}
}
- private void createChatRoom(
- UUID chatRoomId,
- CommandCreateChatRoomTo createChatRoomRequestTo,
- Integer partition)
- {
- log.info(
- "Loading ChatRoom {} for shard {} with buffer-size {}",
- chatRoomId,
- partition,
- bufferSize);
- KafkaChatMessageService service = new KafkaChatMessageService(this, chatRoomId);
- ChatRoomData chatRoomData = new ChatRoomData(
- clock,
- service,
- bufferSize);
- putChatRoom(
- chatRoomId,
- createChatRoomRequestTo.getName(),
- partition,
- chatRoomData);
- }
-
-
private void createChatRoom(ChatRoomInfo chatRoomInfo)
{
- UUID id = chatRoomInfo.getId();
- log.info("Creating ChatRoom {} with buffer-size {}", id, bufferSize);
- KafkaChatMessageService service = new KafkaChatMessageService(this, id);
- ChatRoomData chatRoomData = new ChatRoomData(clock, service, bufferSize);
- putChatRoom(
- chatRoomInfo.getId(),
- chatRoomInfo.getName(),
- chatRoomInfo.getShard(),
- chatRoomData);
- }
-
- private void loadChatMessage(
- UUID chatRoomId,
- LocalDateTime timestamp,
- long offset,
- EventChatMessageReceivedTo chatMessageTo,
- int partition)
- {
- Message.MessageKey key = Message.MessageKey.of(chatMessageTo.getUser(), chatMessageTo.getId());
- Message message = new Message(key, offset, timestamp, chatMessageTo.getText());
+ UUID chatRoomId = chatRoomInfo.getId();
+ Integer partition = chatRoomInfo.getShard();
- ChatRoomData chatRoomData = this.chatRoomData[partition].get(chatRoomId);
- KafkaChatMessageService kafkaChatRoomService =
- (KafkaChatMessageService) chatRoomData.getChatRoomService();
-
- kafkaChatRoomService.persistMessage(message);
- }
-
- private boolean isLoadingCompleted()
- {
- return IntStream
- .range(0, numShards)
- .filter(shard -> isShardOwned[shard])
- .allMatch(shard -> nextOffset[shard] >= currentOffset[shard]);
- }
-
- private void pauseAllOwnedPartions()
- {
- consumer.pause(IntStream
- .range(0, numShards)
- .filter(shard -> isShardOwned[shard])
- .mapToObj(shard -> new TopicPartition(topic, shard))
- .toList());
- }
-
-
- private void putChatRoom(
- UUID chatRoomId,
- String name,
- Integer partition,
- ChatRoomData chatRoomData)
- {
- if (this.chatRoomInfo[partition].containsKey(chatRoomId))
+ if (this.chatRoomInfo.containsKey(chatRoomId))
{
log.warn(
"Ignoring existing chat-room for {}: {}",
else
{
log.info(
- "Adding new chat-room to partition {}: {}",
+ "Adding new chat-room for partition {}: {}",
partition,
- chatRoomData);
-
- this.chatRoomInfo[partition].put(
- chatRoomId,
- new ChatRoomInfo(chatRoomId, name, partition));
- this.chatRoomData[partition].put(chatRoomId, chatRoomData);
- }
- }
-
- int[] getOwnedShards()
- {
- return IntStream
- .range(0, numShards)
- .filter(shard -> isShardOwned[shard])
- .toArray();
- }
-
- Mono<ChatRoomData> getChatRoomData(int shard, UUID id)
- {
- if (loadInProgress)
- {
- return Mono.error(new LoadInProgressException());
- }
+ chatRoomId);
- if (!isShardOwned[shard])
- {
- return Mono.error(new ShardNotOwnedException(shard));
+ this.chatRoomInfo.put(chatRoomId, chatRoomInfo);
}
-
- return Mono.justOrEmpty(chatRoomData[shard].get(id));
}
Flux<ChatRoomInfo> getChatRoomInfo()
{
- return Flux
- .fromStream(IntStream.range(0, numShards).mapToObj(i -> Integer.valueOf(i)))
- .filter(shard -> isShardOwned[shard])
- .flatMap(shard -> Flux.fromIterable(chatRoomInfo[shard].values()));
+ return Flux.fromIterable(chatRoomInfo.values());
}
- Mono<ChatRoomInfo> getChatRoomInfo(int shard, UUID id)
+ Mono<ChatRoomInfo> getChatRoomInfo(UUID id)
{
- if (loadInProgress)
- {
- return Mono.error(new LoadInProgressException());
- }
-
- if (!isShardOwned[shard])
- {
- return Mono.error(new ShardNotOwnedException(shard));
- }
-
- return Mono.justOrEmpty(chatRoomInfo[shard].get(id));
+ return Mono.fromSupplier(() -> chatRoomInfo.get(id));
}
}
projects / demos / kafka / chat / commitdiff