| /** |
| * Licensed to the Apache Software Foundation (ASF) under one |
| * or more contributor license agreements. See the NOTICE file |
| * distributed with this work for additional information |
| * regarding copyright ownership. The ASF licenses this file |
| * to you under the Apache License, Version 2.0 (the |
| * "License"); you may not use this file except in compliance |
| * with the License. You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, |
| * software distributed under the License is distributed on an |
| * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY |
| * KIND, either express or implied. See the License for the |
| * specific language governing permissions and limitations |
| * under the License. |
| */ |
| package org.apache.pulsar.io.kafka.connect; |
| |
| import static com.google.common.base.Preconditions.checkArgument; |
| import static java.nio.charset.StandardCharsets.UTF_8; |
| import static org.apache.commons.lang.StringUtils.isBlank; |
| import io.netty.buffer.ByteBuf; |
| import io.netty.buffer.ByteBufUtil; |
| import io.netty.buffer.Unpooled; |
| import java.io.IOException; |
| import java.nio.ByteBuffer; |
| import java.util.Collection; |
| import java.util.HashMap; |
| import java.util.Map; |
| import java.util.concurrent.CompletableFuture; |
| import java.util.concurrent.ConcurrentHashMap; |
| import java.util.concurrent.ExecutionException; |
| import java.util.concurrent.Future; |
| import lombok.extern.slf4j.Slf4j; |
| import org.apache.kafka.connect.runtime.WorkerConfig; |
| import org.apache.kafka.connect.storage.OffsetBackingStore; |
| import org.apache.kafka.connect.util.Callback; |
| import org.apache.pulsar.client.api.Message; |
| import org.apache.pulsar.client.api.MessageId; |
| import org.apache.pulsar.client.api.Producer; |
| import org.apache.pulsar.client.api.PulsarClient; |
| import org.apache.pulsar.client.api.PulsarClientException; |
| import org.apache.pulsar.client.api.Reader; |
| import org.apache.pulsar.client.api.Schema; |
| |
| /** |
| * Implementation of {@link OffsetBackingStore} that uses a Pulsar topic to store offset data. |
| */ |
| @Slf4j |
| public class PulsarOffsetBackingStore implements OffsetBackingStore { |
| |
| private final Map<ByteBuffer, ByteBuffer> data = new ConcurrentHashMap<>(); |
| private PulsarClient client; |
| private String topic; |
| private Producer<byte[]> producer; |
| private Reader<byte[]> reader; |
| private volatile CompletableFuture<Void> outstandingReadToEnd = null; |
| |
| public PulsarOffsetBackingStore(PulsarClient client) { |
| checkArgument(client != null, "Pulsar Client must be provided"); |
| this.client = client; |
| } |
| |
| @Override |
| public void configure(WorkerConfig workerConfig) { |
| this.topic = workerConfig.getString(PulsarKafkaWorkerConfig.OFFSET_STORAGE_TOPIC_CONFIG); |
| checkArgument(!isBlank(topic), "Offset storage topic must be specified"); |
| |
| log.info("Configure offset backing store on pulsar topic {}", topic); |
| } |
| |
| void readToEnd(CompletableFuture<Void> future) { |
| synchronized (this) { |
| if (outstandingReadToEnd != null) { |
| outstandingReadToEnd.whenComplete((result, cause) -> { |
| if (null != cause) { |
| future.completeExceptionally(cause); |
| } else { |
| future.complete(result); |
| } |
| }); |
| // return if the outstanding read has been issued |
| return; |
| } else { |
| outstandingReadToEnd = future; |
| future.whenComplete((result, cause) -> { |
| synchronized (PulsarOffsetBackingStore.this) { |
| outstandingReadToEnd = null; |
| } |
| }); |
| } |
| } |
| producer.flushAsync().whenComplete((ignored, cause) -> { |
| if (null != cause) { |
| future.completeExceptionally(cause); |
| } else { |
| checkAndReadNext(future); |
| } |
| }); |
| } |
| |
| private void checkAndReadNext(CompletableFuture<Void> endFuture) { |
| reader.hasMessageAvailableAsync().whenComplete((hasMessageAvailable, cause) -> { |
| if (null != cause) { |
| endFuture.completeExceptionally(cause); |
| } else { |
| if (hasMessageAvailable) { |
| readNext(endFuture); |
| } else { |
| endFuture.complete(null); |
| } |
| } |
| }); |
| } |
| |
| private void readNext(CompletableFuture<Void> endFuture) { |
| reader.readNextAsync().whenComplete((message, cause) -> { |
| if (null != cause) { |
| endFuture.completeExceptionally(cause); |
| } else { |
| processMessage(message); |
| checkAndReadNext(endFuture); |
| } |
| }); |
| } |
| |
| void processMessage(Message<byte[]> message) { |
| if (message.getKey() != null) { |
| data.put( |
| ByteBuffer.wrap(message.getKey().getBytes(UTF_8)), |
| ByteBuffer.wrap(message.getValue())); |
| } else { |
| log.debug("Got message without key from the offset storage topic, skip it. message value: {}", |
| message.getValue()); |
| } |
| } |
| |
| @Override |
| public void start() { |
| try { |
| producer = client.newProducer(Schema.BYTES) |
| .topic(topic) |
| .create(); |
| log.info("Successfully created producer to produce updates to topic {}", topic); |
| |
| reader = client.newReader(Schema.BYTES) |
| .topic(topic) |
| .startMessageId(MessageId.earliest) |
| .create(); |
| log.info("Successfully created reader to replay updates from topic {}", topic); |
| |
| CompletableFuture<Void> endFuture = new CompletableFuture<>(); |
| readToEnd(endFuture); |
| endFuture.get(); |
| } catch (PulsarClientException e) { |
| log.error("Failed to setup pulsar producer/reader to cluster", e); |
| throw new RuntimeException("Failed to setup pulsar producer/reader to cluster ", e); |
| } catch (ExecutionException | InterruptedException e) { |
| log.error("Failed to start PulsarOffsetBackingStore", e); |
| throw new RuntimeException("Failed to start PulsarOffsetBackingStore", e); |
| } |
| } |
| |
| @Override |
| public void stop() { |
| log.info("Stopping PulsarOffsetBackingStore"); |
| if (null != producer) { |
| try { |
| producer.flush(); |
| } catch (PulsarClientException pce) { |
| log.warn("Failed to flush the producer", pce); |
| } |
| try { |
| producer.close(); |
| } catch (PulsarClientException e) { |
| log.warn("Failed to close producer", e); |
| } |
| producer = null; |
| } |
| if (null != reader) { |
| try { |
| reader.close(); |
| } catch (IOException e) { |
| log.warn("Failed to close reader", e); |
| } |
| reader = null; |
| } |
| data.clear(); |
| |
| // do not close the client, it is provided by the sink context |
| } |
| |
| @Override |
| public Future<Map<ByteBuffer, ByteBuffer>> get(Collection<ByteBuffer> keys) { |
| CompletableFuture<Void> endFuture = new CompletableFuture<>(); |
| readToEnd(endFuture); |
| return endFuture.thenApply(ignored -> { |
| Map<ByteBuffer, ByteBuffer> values = new HashMap<>(); |
| for (ByteBuffer key : keys) { |
| ByteBuffer value = data.get(key); |
| if (null != value) { |
| values.put(key, value); |
| } |
| } |
| return values; |
| }); |
| } |
| |
| @Override |
| public Future<Void> set(Map<ByteBuffer, ByteBuffer> values, Callback<Void> callback) { |
| values.forEach((key, value) -> { |
| ByteBuf bb = Unpooled.wrappedBuffer(key); |
| byte[] keyBytes = ByteBufUtil.getBytes(bb); |
| bb = Unpooled.wrappedBuffer(value); |
| byte[] valBytes = ByteBufUtil.getBytes(bb); |
| producer.newMessage() |
| .key(new String(keyBytes, UTF_8)) |
| .value(valBytes) |
| .sendAsync(); |
| }); |
| return producer.flushAsync().whenComplete((ignored, cause) -> { |
| if (null != callback) { |
| callback.onCompletion(cause, ignored); |
| } |
| if (null == cause) { |
| readToEnd(new CompletableFuture<>()); |
| } |
| }); |
| } |
| } |