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Posted to commits@flink.apache.org by se...@apache.org on 2015/08/26 21:13:59 UTC
[09/10] flink git commit: [FLINK-2386] [kafka] Move Kafka connectors
to 'org.apache.flink.streaming.connectors.kafka'
http://git-wip-us.apache.org/repos/asf/flink/blob/9f2f6b7b/flink-staging/flink-streaming/flink-streaming-connectors/flink-connector-kafka/src/main/java/org/apache/flink/streaming/connectors/kafka/FlinkKafkaConsumer.java
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diff --git a/flink-staging/flink-streaming/flink-streaming-connectors/flink-connector-kafka/src/main/java/org/apache/flink/streaming/connectors/kafka/FlinkKafkaConsumer.java b/flink-staging/flink-streaming/flink-streaming-connectors/flink-connector-kafka/src/main/java/org/apache/flink/streaming/connectors/kafka/FlinkKafkaConsumer.java
new file mode 100644
index 0000000..a98e84c
--- /dev/null
+++ b/flink-staging/flink-streaming/flink-streaming-connectors/flink-connector-kafka/src/main/java/org/apache/flink/streaming/connectors/kafka/FlinkKafkaConsumer.java
@@ -0,0 +1,680 @@
+/*
+ * 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.flink.streaming.connectors.kafka;
+
+import kafka.cluster.Broker;
+import kafka.common.ErrorMapping;
+import kafka.javaapi.PartitionMetadata;
+import kafka.javaapi.TopicMetadata;
+import kafka.javaapi.TopicMetadataRequest;
+import kafka.javaapi.consumer.SimpleConsumer;
+import org.apache.commons.collections.map.LinkedMap;
+
+import org.apache.flink.api.common.typeinfo.TypeInformation;
+import org.apache.flink.api.java.typeutils.ResultTypeQueryable;
+import org.apache.flink.configuration.Configuration;
+import org.apache.flink.streaming.api.checkpoint.CheckpointCommitter;
+import org.apache.flink.streaming.api.checkpoint.CheckpointedAsynchronously;
+import org.apache.flink.streaming.api.functions.source.RichParallelSourceFunction;
+import org.apache.flink.streaming.connectors.kafka.internals.Fetcher;
+import org.apache.flink.streaming.connectors.kafka.internals.LegacyFetcher;
+import org.apache.flink.streaming.connectors.kafka.internals.OffsetHandler;
+import org.apache.flink.streaming.connectors.kafka.internals.ZookeeperOffsetHandler;
+import org.apache.flink.streaming.util.serialization.DeserializationSchema;
+
+import org.apache.flink.util.NetUtils;
+import org.apache.kafka.clients.consumer.ConsumerConfig;
+import org.apache.kafka.common.Node;
+import org.apache.kafka.common.PartitionInfo;
+import org.apache.kafka.common.TopicPartition;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+import java.io.IOException;
+import java.net.URL;
+import java.util.ArrayList;
+import java.util.Arrays;
+import java.util.Collections;
+import java.util.HashMap;
+import java.util.List;
+import java.util.Map;
+import java.util.Properties;
+import java.util.Random;
+
+import static com.google.common.base.Preconditions.checkArgument;
+import static com.google.common.base.Preconditions.checkNotNull;
+
+/**
+ * The Flink Kafka Consumer is a streaming data source that pulls a parallel data stream from
+ * Apache Kafka. The consumer can run in multiple parallel instances, each of which will pull
+ * data from one or more Kafka partitions.
+ *
+ * <p>The Flink Kafka Consumer participates in checkpointing and guarantees that no data is lost
+ * during a failure, and that the computation processes elements "exactly once".
+ * (Note: These guarantees naturally assume that Kafka itself does not loose any data.)</p>
+ *
+ * <p>To support a variety of Kafka brokers, protocol versions, and offset committing approaches,
+ * the Flink Kafka Consumer can be parametrized with a <i>fetcher</i> and an <i>offset handler</i>.</p>
+ *
+ * <h1>Fetcher</h1>
+ *
+ * <p>The fetcher is responsible to pull data from Kafka. Because Kafka has undergone a change in
+ * protocols and APIs, there are currently two fetchers available:</p>
+ *
+ * <ul>
+ * <li>{@link FetcherType#NEW_HIGH_LEVEL}: A fetcher based on the new Kafka consumer API.
+ * This fetcher is generally more robust, but works only with later versions of
+ * Kafka (> 0.8.2).</li>
+ *
+ * <li>{@link FetcherType#LEGACY_LOW_LEVEL}: A fetcher based on the old low-level consumer API.
+ * This fetcher is works also with older versions of Kafka (0.8.1). The fetcher interprets
+ * the old Kafka consumer properties, like:
+ * <ul>
+ * <li>socket.timeout.ms</li>
+ * <li>socket.receive.buffer.bytes</li>
+ * <li>fetch.message.max.bytes</li>
+ * <li>auto.offset.reset with the values "latest", "earliest" (unlike 0.8.2 behavior)</li>
+ * <li>fetch.wait.max.ms</li>
+ * </ul>
+ * </li>
+ * </ul>
+ *
+ * <h1>Offset handler</h1>
+ *
+ * <p>Offsets whose records have been read and are checkpointed will be committed back to Kafka / ZooKeeper
+ * by the offset handler. In addition, the offset handler finds the point where the source initially
+ * starts reading from the stream, when the streaming job is started.</p>
+ *
+ * <p>Currently, the source offers two different offset handlers exist:</p>
+ * <ul>
+ * <li>{@link OffsetStore#KAFKA}: Use this offset handler when the Kafka brokers are managing the offsets,
+ * and hence offsets need to be committed the Kafka brokers, rather than to ZooKeeper.
+ * Note that this offset handler works only on new versions of Kafka (0.8.2.x +) and
+ * with the {@link FetcherType#NEW_HIGH_LEVEL} fetcher.</li>
+ *
+ * <li>{@link OffsetStore#FLINK_ZOOKEEPER}: Use this offset handler when the offsets are managed
+ * by ZooKeeper, as in older versions of Kafka (0.8.1.x)</li>
+ * </ul>
+ *
+ * <p>Please note that Flink snapshots the offsets internally as part of its distributed checkpoints. The offsets
+ * committed to Kafka / ZooKeeper are only to bring the outside view of progress in sync with Flink's view
+ * of the progress. That way, monitoring and other jobs can get a view of how far the Flink Kafka consumer
+ * has consumed a topic.</p>
+ *
+ * <p><b>NOTE:</b> The implementation currently accesses partition metadata when the consumer
+ * is constructed. That means that the client that submits the program needs to be able to
+ * reach the Kafka brokers or ZooKeeper.</p>
+ */
+public class FlinkKafkaConsumer<T> extends RichParallelSourceFunction<T>
+ implements CheckpointCommitter, CheckpointedAsynchronously<long[]>, ResultTypeQueryable<T> {
+
+ /**
+ * The offset store defines how acknowledged offsets are committed back to Kafka. Different
+ * options include letting Flink periodically commit to ZooKeeper, or letting Kafka manage the
+ * offsets (new Kafka versions only).
+ */
+ public enum OffsetStore {
+
+ /**
+ * Let Flink manage the offsets. Flink will periodically commit them to Zookeeper (usually after
+ * successful checkpoints), in the same structure as Kafka 0.8.2.x
+ *
+ * <p>Use this mode when using the source with Kafka 0.8.1.x brokers.</p>
+ */
+ FLINK_ZOOKEEPER,
+
+ /**
+ * Use the mechanisms in Kafka to commit offsets. Depending on the Kafka configuration, different
+ * mechanism will be used (broker coordinator, zookeeper)
+ */
+ KAFKA
+ }
+
+ /**
+ * The fetcher type defines which code paths to use to pull data from teh Kafka broker.
+ */
+ public enum FetcherType {
+
+ /**
+ * The legacy fetcher uses Kafka's old low-level consumer API.
+ *
+ * <p>Use this fetcher for Kafka 0.8.1 brokers.</p>
+ */
+ LEGACY_LOW_LEVEL,
+
+ /**
+ * This fetcher uses a backport of the new consumer API to pull data from the Kafka broker.
+ * It is the fetcher that will be maintained in the future, and it already
+ * handles certain failure cases with less overhead than the legacy fetcher.
+ *
+ * <p>This fetcher works only Kafka 0.8.2 and 0.8.3 (and future versions).</p>
+ */
+ NEW_HIGH_LEVEL
+ }
+
+ // ------------------------------------------------------------------------
+
+ private static final long serialVersionUID = -6272159445203409112L;
+
+ private static final Logger LOG = LoggerFactory.getLogger(FlinkKafkaConsumer.class);
+
+ /** Magic number to define an unset offset. Negative offsets are not used by Kafka (invalid),
+ * and we pick a number that is probably (hopefully) not used by Kafka as a magic number for anything else. */
+ public static final long OFFSET_NOT_SET = -915623761776L;
+
+ /** The maximum number of pending non-committed checkpoints to track, to avoid memory leaks */
+ public static final int MAX_NUM_PENDING_CHECKPOINTS = 100;
+
+ /** Configuration key for the number of retries for getting the partition info */
+ public static final String GET_PARTITIONS_RETRIES_KEY = "flink.get-partitions.retry";
+
+ /** Default number of retries for getting the partition info. One retry means going through the full list of brokers */
+ public static final int DEFAULT_GET_PARTITIONS_RETRIES = 3;
+
+
+
+ // ------ Configuration of the Consumer -------
+
+ /** The offset store where this consumer commits safe offsets */
+ private final OffsetStore offsetStore;
+
+ /** The type of fetcher to be used to pull data from Kafka */
+ private final FetcherType fetcherType;
+
+ /** name of the topic consumed by this source */
+ private final String topic;
+
+ /** The properties to parametrize the Kafka consumer and ZooKeeper client */
+ private final Properties props;
+
+ /** The ids of the partitions that are read by this consumer */
+ private final int[] partitions;
+
+ /** The schema to convert between Kafka#s byte messages, and Flink's objects */
+ private final DeserializationSchema<T> valueDeserializer;
+
+ // ------ Runtime State -------
+
+ /** Data for pending but uncommitted checkpoints */
+ private final LinkedMap pendingCheckpoints = new LinkedMap();
+
+ /** The fetcher used to pull data from the Kafka brokers */
+ private transient Fetcher fetcher;
+
+ /** The committer that persists the committed offsets */
+ private transient OffsetHandler offsetHandler;
+
+ /** The partitions actually handled by this consumer */
+ private transient List<TopicPartition> subscribedPartitions;
+
+ /** The offsets of the last returned elements */
+ private transient long[] lastOffsets;
+
+ /** The latest offsets that have been committed to Kafka or ZooKeeper. These are never
+ * newer then the last offsets (Flink's internal view is fresher) */
+ private transient long[] commitedOffsets;
+
+ /** The offsets to restore to, if the consumer restores state from a checkpoint */
+ private transient long[] restoreToOffset;
+
+ private volatile boolean running = true;
+
+ // ------------------------------------------------------------------------
+
+ /**
+ * Creates a new Flink Kafka Consumer, using the given type of fetcher and offset handler.
+ *
+ * <p>To determine which kink of fetcher and offset handler to use, please refer to the docs
+ * at the beginnign of this class.</p>
+ *
+ * @param topic
+ * The Kafka topic to read from.
+ * @param valueDeserializer
+ * The deserializer to turn raw byte messages into Java/Scala objects.
+ * @param props
+ * The properties that are used to configure both the fetcher and the offset handler.
+ * @param offsetStore
+ * The type of offset store to use (Kafka / ZooKeeper)
+ * @param fetcherType
+ * The type of fetcher to use (new high-level API, old low-level API).
+ */
+ public FlinkKafkaConsumer(String topic, DeserializationSchema<T> valueDeserializer, Properties props,
+ OffsetStore offsetStore, FetcherType fetcherType) {
+ this.offsetStore = checkNotNull(offsetStore);
+ this.fetcherType = checkNotNull(fetcherType);
+
+ if(fetcherType == FetcherType.NEW_HIGH_LEVEL) {
+ throw new UnsupportedOperationException("The fetcher for Kafka 0.8.3 is not yet " +
+ "supported in Flink");
+ }
+ if (offsetStore == OffsetStore.KAFKA && fetcherType == FetcherType.LEGACY_LOW_LEVEL) {
+ throw new IllegalArgumentException(
+ "The Kafka offset handler cannot be used together with the old low-level fetcher.");
+ }
+
+ this.topic = checkNotNull(topic, "topic");
+ this.props = checkNotNull(props, "props");
+ this.valueDeserializer = checkNotNull(valueDeserializer, "valueDeserializer");
+
+ // validate the zookeeper properties
+ if (offsetStore == OffsetStore.FLINK_ZOOKEEPER) {
+ validateZooKeeperConfig(props);
+ }
+
+ // Connect to a broker to get the partitions
+ List<PartitionInfo> partitionInfos = getPartitionsForTopic(topic, props);
+
+ // get initial partitions list. The order of the partitions is important for consistent
+ // partition id assignment in restart cases.
+ this.partitions = new int[partitionInfos.size()];
+ for (int i = 0; i < partitionInfos.size(); i++) {
+ partitions[i] = partitionInfos.get(i).partition();
+
+ if (partitions[i] >= partitions.length) {
+ throw new RuntimeException("Kafka partition numbers are sparse");
+ }
+ }
+ LOG.info("Topic {} has {} partitions", topic, partitions.length);
+
+ // make sure that we take care of the committing
+ props.setProperty("enable.auto.commit", "false");
+ }
+
+ // ------------------------------------------------------------------------
+ // Source life cycle
+ // ------------------------------------------------------------------------
+
+ @Override
+ public void open(Configuration parameters) throws Exception {
+ super.open(parameters);
+
+ final int numConsumers = getRuntimeContext().getNumberOfParallelSubtasks();
+ final int thisComsumerIndex = getRuntimeContext().getIndexOfThisSubtask();
+
+ // pick which partitions we work on
+ subscribedPartitions = assignPartitions(this.partitions, this.topic, numConsumers, thisComsumerIndex);
+
+ if (LOG.isInfoEnabled()) {
+ LOG.info("Kafka consumer {} will read partitions {} out of partitions {}",
+ thisComsumerIndex, subscribedPartitions, Arrays.toString(partitions));
+ }
+
+ // we leave the fetcher as null, if we have no partitions
+ if (subscribedPartitions.isEmpty()) {
+ LOG.info("Kafka consumer {} has no partitions (empty source)", thisComsumerIndex);
+ return;
+ }
+
+ // create fetcher
+ switch (fetcherType){
+ case NEW_HIGH_LEVEL:
+ throw new UnsupportedOperationException("Currently unsupported");
+ case LEGACY_LOW_LEVEL:
+ fetcher = new LegacyFetcher(topic, props, getRuntimeContext().getTaskName());
+ break;
+ default:
+ throw new RuntimeException("Requested unknown fetcher " + fetcher);
+ }
+ fetcher.setPartitionsToRead(subscribedPartitions);
+
+ // offset handling
+ switch (offsetStore){
+ case FLINK_ZOOKEEPER:
+ offsetHandler = new ZookeeperOffsetHandler(props);
+ break;
+ case KAFKA:
+ throw new Exception("Kafka offset handler cannot work with legacy fetcher");
+ default:
+ throw new RuntimeException("Requested unknown offset store " + offsetStore);
+ }
+
+ // set up operator state
+ lastOffsets = new long[partitions.length];
+ commitedOffsets = new long[partitions.length];
+
+ Arrays.fill(lastOffsets, OFFSET_NOT_SET);
+ Arrays.fill(commitedOffsets, OFFSET_NOT_SET);
+
+ // seek to last known pos, from restore request
+ if (restoreToOffset != null) {
+ if (LOG.isInfoEnabled()) {
+ LOG.info("Consumer {} found offsets from previous checkpoint: {}",
+ thisComsumerIndex, Arrays.toString(restoreToOffset));
+ }
+
+ for (int i = 0; i < restoreToOffset.length; i++) {
+ long restoredOffset = restoreToOffset[i];
+ if (restoredOffset != OFFSET_NOT_SET) {
+ // if this fails because we are not subscribed to the topic, then the
+ // partition assignment is not deterministic!
+
+ // we set the offset +1 here, because seek() is accepting the next offset to read,
+ // but the restore offset is the last read offset
+ fetcher.seek(new TopicPartition(topic, i), restoredOffset + 1);
+ lastOffsets[i] = restoredOffset;
+ }
+ }
+ }
+ else {
+ // no restore request. Let the offset handler take care of the initial offset seeking
+ offsetHandler.seekFetcherToInitialOffsets(subscribedPartitions, fetcher);
+ }
+ }
+
+ @Override
+ public void run(SourceContext<T> sourceContext) throws Exception {
+ if (fetcher != null) {
+ fetcher.run(sourceContext, valueDeserializer, lastOffsets);
+ }
+ else {
+ // this source never completes
+ final Object waitLock = new Object();
+ while (running) {
+ // wait until we are canceled
+ try {
+ //noinspection SynchronizationOnLocalVariableOrMethodParameter
+ synchronized (waitLock) {
+ waitLock.wait();
+ }
+ }
+ catch (InterruptedException e) {
+ // do nothing, check our "running" status
+ }
+ }
+ }
+ }
+
+ @Override
+ public void cancel() {
+ // set ourselves as not running
+ running = false;
+
+ // close the fetcher to interrupt any work
+ Fetcher fetcher = this.fetcher;
+ this.fetcher = null;
+ if (fetcher != null) {
+ try {
+ fetcher.close();
+ }
+ catch (IOException e) {
+ LOG.warn("Error while closing Kafka connector data fetcher", e);
+ }
+ }
+
+ OffsetHandler offsetHandler = this.offsetHandler;
+ this.offsetHandler = null;
+ if (offsetHandler != null) {
+ try {
+ offsetHandler.close();
+ }
+ catch (IOException e) {
+ LOG.warn("Error while closing Kafka connector offset handler", e);
+ }
+ }
+ }
+
+ @Override
+ public void close() throws Exception {
+ cancel();
+ super.close();
+ }
+
+ @Override
+ public TypeInformation<T> getProducedType() {
+ return valueDeserializer.getProducedType();
+ }
+
+ // ------------------------------------------------------------------------
+ // Checkpoint and restore
+ // ------------------------------------------------------------------------
+
+ @Override
+ public long[] snapshotState(long checkpointId, long checkpointTimestamp) throws Exception {
+ if (lastOffsets == null) {
+ LOG.debug("snapshotState() requested on not yet opened source; returning null.");
+ return null;
+ }
+ if (!running) {
+ LOG.debug("snapshotState() called on closed source");
+ return null;
+ }
+
+ if (LOG.isDebugEnabled()) {
+ LOG.debug("Snapshotting state. Offsets: {}, checkpoint id: {}, timestamp: {}",
+ Arrays.toString(lastOffsets), checkpointId, checkpointTimestamp);
+ }
+
+ long[] currentOffsets = Arrays.copyOf(lastOffsets, lastOffsets.length);
+
+ // the map cannot be asynchronously updated, because only one checkpoint call can happen
+ // on this function at a time: either snapshotState() or notifyCheckpointComplete()
+ pendingCheckpoints.put(checkpointId, currentOffsets);
+
+ while (pendingCheckpoints.size() > MAX_NUM_PENDING_CHECKPOINTS) {
+ pendingCheckpoints.remove(0);
+ }
+
+ return currentOffsets;
+ }
+
+ @Override
+ public void restoreState(long[] restoredOffsets) {
+ restoreToOffset = restoredOffsets;
+ }
+
+ @Override
+ public void commitCheckpoint(long checkpointId) {
+ if (fetcher == null) {
+ LOG.debug("notifyCheckpointComplete() called on uninitialized source");
+ return;
+ }
+ if (!running) {
+ LOG.debug("notifyCheckpointComplete() called on closed source");
+ return;
+ }
+
+ // only one commit operation must be in progress
+ if (LOG.isDebugEnabled()) {
+ LOG.debug("Committing offsets externally for checkpoint {}", checkpointId);
+ }
+
+ long[] checkpointOffsets;
+
+ // the map may be asynchronously updates when snapshotting state, so we synchronize
+ synchronized (pendingCheckpoints) {
+ final int posInMap = pendingCheckpoints.indexOf(checkpointId);
+ if (posInMap == -1) {
+ LOG.warn("Received confirmation for unknown checkpoint id {}", checkpointId);
+ return;
+ }
+
+ checkpointOffsets = (long[]) pendingCheckpoints.remove(posInMap);
+
+ // remove older checkpoints in map
+ for (int i = 0; i < posInMap; i++) {
+ pendingCheckpoints.remove(0);
+ }
+ }
+
+ if (LOG.isInfoEnabled()) {
+ LOG.info("Committing offsets {} to offset store: {}", Arrays.toString(checkpointOffsets), offsetStore);
+ }
+
+ // build the map of (topic,partition) -> committed offset
+ Map<TopicPartition, Long> offsetsToCommit = new HashMap<TopicPartition, Long>();
+ for (TopicPartition tp : subscribedPartitions) {
+
+ int partition = tp.partition();
+ long offset = checkpointOffsets[partition];
+ long lastCommitted = commitedOffsets[partition];
+
+ if (offset != OFFSET_NOT_SET) {
+ if (offset > lastCommitted) {
+ offsetsToCommit.put(tp, offset);
+ LOG.debug("Committing offset {} for partition {}", offset, partition);
+ }
+ else {
+ LOG.debug("Ignoring offset {} for partition {} because it is already committed", offset, partition);
+ }
+ }
+ }
+ try {
+ offsetHandler.commit(offsetsToCommit);
+ } catch(Exception e) {
+ throw new RuntimeException("Unable to commit offset", e);
+ }
+ }
+
+ // ------------------------------------------------------------------------
+ // Miscellaneous utilities
+ // ------------------------------------------------------------------------
+
+ protected static List<TopicPartition> assignPartitions(int[] partitions, String topicName,
+ int numConsumers, int consumerIndex) {
+ checkArgument(numConsumers > 0);
+ checkArgument(consumerIndex < numConsumers);
+
+ List<TopicPartition> partitionsToSub = new ArrayList<TopicPartition>();
+
+ for (int i = 0; i < partitions.length; i++) {
+ if (i % numConsumers == consumerIndex) {
+ partitionsToSub.add(new TopicPartition(topicName, partitions[i]));
+ }
+ }
+ return partitionsToSub;
+ }
+
+ // ------------------------------------------------------------------------
+ // Kafka / ZooKeeper communication utilities
+ // ------------------------------------------------------------------------
+
+ /**
+ * Send request to Kafka to get partitions for topic.
+ *
+ * @param topic The name of the topic.
+ * @param properties The properties for the Kafka Consumer that is used to query the partitions for the topic.
+ */
+ public static List<PartitionInfo> getPartitionsForTopic(final String topic, final Properties properties) {
+ String seedBrokersConfString = properties.getProperty(ConsumerConfig.BOOTSTRAP_SERVERS_CONFIG);
+ final int numRetries = Integer.valueOf(properties.getProperty(GET_PARTITIONS_RETRIES_KEY, Integer.toString(DEFAULT_GET_PARTITIONS_RETRIES)));
+
+ checkNotNull(seedBrokersConfString, "Configuration property " + ConsumerConfig.BOOTSTRAP_SERVERS_CONFIG + " not set");
+ String[] seedBrokers = seedBrokersConfString.split(",");
+ List<PartitionInfo> partitions = new ArrayList<PartitionInfo>();
+
+ Random rnd = new Random();
+ retryLoop: for(int retry = 0; retry < numRetries; retry++) {
+ // we pick a seed broker randomly to avoid overloading the first broker with all the requests when the
+ // parallel source instances start. Still, we try all available brokers.
+ int index = rnd.nextInt(seedBrokers.length);
+ brokersLoop: for (int arrIdx = 0; arrIdx < seedBrokers.length; arrIdx++) {
+ String seedBroker = seedBrokers[index];
+ LOG.info("Trying to get topic metadata from broker {} in try {}/{}", seedBroker, retry, numRetries);
+ if (++index == seedBrokers.length) {
+ index = 0;
+ }
+
+ URL brokerUrl = NetUtils.getHostnamePort(seedBroker);
+ SimpleConsumer consumer = null;
+ try {
+ final String clientId = "flink-kafka-consumer-partition-lookup";
+ final int soTimeout = Integer.valueOf(properties.getProperty("socket.timeout.ms", "30000"));
+ final int bufferSize = Integer.valueOf(properties.getProperty("socket.receive.buffer.bytes", "65536"));
+ consumer = new SimpleConsumer(brokerUrl.getHost(), brokerUrl.getPort(), soTimeout, bufferSize, clientId);
+
+ List<String> topics = Collections.singletonList(topic);
+ TopicMetadataRequest req = new TopicMetadataRequest(topics);
+ kafka.javaapi.TopicMetadataResponse resp = consumer.send(req);
+
+ List<TopicMetadata> metaData = resp.topicsMetadata();
+
+ // clear in case we have an incomplete list from previous tries
+ partitions.clear();
+ for (TopicMetadata item : metaData) {
+ if (item.errorCode() != ErrorMapping.NoError()) {
+ if (item.errorCode() == ErrorMapping.InvalidTopicCode() || item.errorCode() == ErrorMapping.UnknownTopicOrPartitionCode()) {
+ // fail hard if topic is unknown
+ throw new RuntimeException("Requested partitions for unknown topic", ErrorMapping.exceptionFor(item.errorCode()));
+ }
+ // warn and try more brokers
+ LOG.warn("Error while getting metadata from broker " + seedBroker + " to find partitions for " + topic,
+ ErrorMapping.exceptionFor(item.errorCode()));
+ continue brokersLoop;
+ }
+ if (!item.topic().equals(topic)) {
+ LOG.warn("Received metadata from topic " + item.topic() + " even though it was not requested. Skipping ...");
+ continue brokersLoop;
+ }
+ for (PartitionMetadata part : item.partitionsMetadata()) {
+ Node leader = brokerToNode(part.leader());
+ Node[] replicas = new Node[part.replicas().size()];
+ for (int i = 0; i < part.replicas().size(); i++) {
+ replicas[i] = brokerToNode(part.replicas().get(i));
+ }
+
+ Node[] ISRs = new Node[part.isr().size()];
+ for (int i = 0; i < part.isr().size(); i++) {
+ ISRs[i] = brokerToNode(part.isr().get(i));
+ }
+ PartitionInfo pInfo = new PartitionInfo(topic, part.partitionId(), leader, replicas, ISRs);
+ partitions.add(pInfo);
+ }
+ }
+ break retryLoop; // leave the loop through the brokers
+ } catch (Exception e) {
+ LOG.warn("Error communicating with broker " + seedBroker + " to find partitions for " + topic, e);
+ } finally {
+ if (consumer != null) {
+ consumer.close();
+ }
+ }
+ } // brokers loop
+ } // retries loop
+ return partitions;
+ }
+
+ private static Node brokerToNode(Broker broker) {
+ return new Node(broker.id(), broker.host(), broker.port());
+ }
+
+ protected static void validateZooKeeperConfig(Properties props) {
+ if (props.getProperty("zookeeper.connect") == null) {
+ throw new IllegalArgumentException("Required property 'zookeeper.connect' has not been set in the properties");
+ }
+ if (props.getProperty(ConsumerConfig.GROUP_ID_CONFIG) == null) {
+ throw new IllegalArgumentException("Required property '" + ConsumerConfig.GROUP_ID_CONFIG
+ + "' has not been set in the properties");
+ }
+
+ try {
+ //noinspection ResultOfMethodCallIgnored
+ Integer.parseInt(props.getProperty("zookeeper.session.timeout.ms", "0"));
+ }
+ catch (NumberFormatException e) {
+ throw new IllegalArgumentException("Property 'zookeeper.session.timeout.ms' is not a valid integer");
+ }
+
+ try {
+ //noinspection ResultOfMethodCallIgnored
+ Integer.parseInt(props.getProperty("zookeeper.connection.timeout.ms", "0"));
+ }
+ catch (NumberFormatException e) {
+ throw new IllegalArgumentException("Property 'zookeeper.connection.timeout.ms' is not a valid integer");
+ }
+ }
+}
http://git-wip-us.apache.org/repos/asf/flink/blob/9f2f6b7b/flink-staging/flink-streaming/flink-streaming-connectors/flink-connector-kafka/src/main/java/org/apache/flink/streaming/connectors/kafka/FlinkKafkaConsumer081.java
----------------------------------------------------------------------
diff --git a/flink-staging/flink-streaming/flink-streaming-connectors/flink-connector-kafka/src/main/java/org/apache/flink/streaming/connectors/kafka/FlinkKafkaConsumer081.java b/flink-staging/flink-streaming/flink-streaming-connectors/flink-connector-kafka/src/main/java/org/apache/flink/streaming/connectors/kafka/FlinkKafkaConsumer081.java
new file mode 100644
index 0000000..21f24e6
--- /dev/null
+++ b/flink-staging/flink-streaming/flink-streaming-connectors/flink-connector-kafka/src/main/java/org/apache/flink/streaming/connectors/kafka/FlinkKafkaConsumer081.java
@@ -0,0 +1,57 @@
+/*
+ * 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.flink.streaming.connectors.kafka;
+
+import org.apache.flink.streaming.util.serialization.DeserializationSchema;
+
+import java.util.Properties;
+
+/**
+ * Creates a Kafka consumer compatible with reading from Kafka 0.8.1.x brokers.
+ * The consumer will internally use the old low-level Kafka API, and manually commit offsets
+ * partition offsets to ZooKeeper.
+ *
+ * <p>The following additional configuration values are available:</p>
+ * <ul>
+ * <li>socket.timeout.ms</li>
+ * <li>socket.receive.buffer.bytes</li>
+ * <li>fetch.message.max.bytes</li>
+ * <li>auto.offset.reset with the values "latest", "earliest" (unlike 0.8.2 behavior)</li>
+ * <li>fetch.wait.max.ms</li>
+ * </ul>
+ *
+ * @param <T> The type of elements produced by this consumer.
+ */
+public class FlinkKafkaConsumer081<T> extends FlinkKafkaConsumer<T> {
+
+ private static final long serialVersionUID = -5649906773771949146L;
+
+ /**
+ * Creates a new Kafka 0.8.1.x streaming source consumer.
+ *
+ * @param topic
+ * The name of the topic that should be consumed.
+ * @param valueDeserializer
+ * The de-/serializer used to convert between Kafka's byte messages and Flink's objects.
+ * @param props
+ * The properties used to configure the Kafka consumer client, and the ZooKeeper client.
+ */
+ public FlinkKafkaConsumer081(String topic, DeserializationSchema<T> valueDeserializer, Properties props) {
+ super(topic, valueDeserializer, props, OffsetStore.FLINK_ZOOKEEPER, FetcherType.LEGACY_LOW_LEVEL);
+ }
+}
http://git-wip-us.apache.org/repos/asf/flink/blob/9f2f6b7b/flink-staging/flink-streaming/flink-streaming-connectors/flink-connector-kafka/src/main/java/org/apache/flink/streaming/connectors/kafka/FlinkKafkaConsumer082.java
----------------------------------------------------------------------
diff --git a/flink-staging/flink-streaming/flink-streaming-connectors/flink-connector-kafka/src/main/java/org/apache/flink/streaming/connectors/kafka/FlinkKafkaConsumer082.java b/flink-staging/flink-streaming/flink-streaming-connectors/flink-connector-kafka/src/main/java/org/apache/flink/streaming/connectors/kafka/FlinkKafkaConsumer082.java
new file mode 100644
index 0000000..77e41e5
--- /dev/null
+++ b/flink-staging/flink-streaming/flink-streaming-connectors/flink-connector-kafka/src/main/java/org/apache/flink/streaming/connectors/kafka/FlinkKafkaConsumer082.java
@@ -0,0 +1,51 @@
+/*
+ * 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.flink.streaming.connectors.kafka;
+
+import org.apache.flink.streaming.util.serialization.DeserializationSchema;
+
+import java.util.Properties;
+
+/**
+ * Creates a Kafka consumer compatible with reading from Kafka 0.8.2.x brokers.
+ * The consumer will internally use the old low-level Kafka API, and manually commit offsets
+ * partition offsets to ZooKeeper.
+ *
+ * Once Kafka released the new consumer with Kafka 0.8.3 Flink might use the 0.8.3 consumer API
+ * also against Kafka 0.8.2 installations.
+ *
+ * @param <T> The type of elements produced by this consumer.
+ */
+public class FlinkKafkaConsumer082<T> extends FlinkKafkaConsumer<T> {
+
+ private static final long serialVersionUID = -8450689820627198228L;
+
+ /**
+ * Creates a new Kafka 0.8.2.x streaming source consumer.
+ *
+ * @param topic
+ * The name of the topic that should be consumed.
+ * @param valueDeserializer
+ * The de-/serializer used to convert between Kafka's byte messages and Flink's objects.
+ * @param props
+ * The properties used to configure the Kafka consumer client, and the ZooKeeper client.
+ */
+ public FlinkKafkaConsumer082(String topic, DeserializationSchema<T> valueDeserializer, Properties props) {
+ super(topic, valueDeserializer, props, OffsetStore.FLINK_ZOOKEEPER, FetcherType.LEGACY_LOW_LEVEL);
+ }
+}
http://git-wip-us.apache.org/repos/asf/flink/blob/9f2f6b7b/flink-staging/flink-streaming/flink-streaming-connectors/flink-connector-kafka/src/main/java/org/apache/flink/streaming/connectors/kafka/KafkaSink.java
----------------------------------------------------------------------
diff --git a/flink-staging/flink-streaming/flink-streaming-connectors/flink-connector-kafka/src/main/java/org/apache/flink/streaming/connectors/kafka/KafkaSink.java b/flink-staging/flink-streaming/flink-streaming-connectors/flink-connector-kafka/src/main/java/org/apache/flink/streaming/connectors/kafka/KafkaSink.java
new file mode 100644
index 0000000..ebda603
--- /dev/null
+++ b/flink-staging/flink-streaming/flink-streaming-connectors/flink-connector-kafka/src/main/java/org/apache/flink/streaming/connectors/kafka/KafkaSink.java
@@ -0,0 +1,187 @@
+/*
+ * 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.flink.streaming.connectors.kafka;
+
+import com.google.common.base.Preconditions;
+import kafka.javaapi.producer.Producer;
+import kafka.producer.KeyedMessage;
+import kafka.producer.ProducerConfig;
+import kafka.serializer.DefaultEncoder;
+import org.apache.flink.api.java.ClosureCleaner;
+import org.apache.flink.configuration.Configuration;
+import org.apache.flink.streaming.api.functions.sink.RichSinkFunction;
+import org.apache.flink.streaming.connectors.kafka.internals.PartitionerWrapper;
+import org.apache.flink.streaming.util.serialization.SerializationSchema;
+import org.apache.flink.util.NetUtils;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+import java.util.Map;
+import java.util.Properties;
+
+
+/**
+ * Sink that emits its inputs to a Kafka topic.
+ *
+ * @param <IN>
+ * Type of the sink input
+ */
+public class KafkaSink<IN> extends RichSinkFunction<IN> {
+
+ private static final long serialVersionUID = 1L;
+
+ private static final Logger LOG = LoggerFactory.getLogger(KafkaSink.class);
+
+ private Producer<IN, byte[]> producer;
+ private Properties userDefinedProperties;
+ private String topicId;
+ private String brokerList;
+ private SerializationSchema<IN, byte[]> schema;
+ private SerializableKafkaPartitioner partitioner;
+ private Class<? extends SerializableKafkaPartitioner> partitionerClass = null;
+
+ /**
+ * Creates a KafkaSink for a given topic. The sink produces its input to
+ * the topic.
+ *
+ * @param brokerList
+ * Addresses of the brokers
+ * @param topicId
+ * ID of the Kafka topic.
+ * @param serializationSchema
+ * User defined serialization schema.
+ */
+ public KafkaSink(String brokerList, String topicId, SerializationSchema<IN, byte[]> serializationSchema) {
+ this(brokerList, topicId, new Properties(), serializationSchema);
+ }
+
+ /**
+ * Creates a KafkaSink for a given topic with custom Producer configuration.
+ * If you use this constructor, the broker should be set with the "metadata.broker.list"
+ * configuration.
+ *
+ * @param brokerList
+ * Addresses of the brokers
+ * @param topicId
+ * ID of the Kafka topic.
+ * @param producerConfig
+ * Configurations of the Kafka producer
+ * @param serializationSchema
+ * User defined serialization schema.
+ */
+ public KafkaSink(String brokerList, String topicId, Properties producerConfig, SerializationSchema<IN, byte[]> serializationSchema) {
+ String[] elements = brokerList.split(",");
+ for(String broker: elements) {
+ NetUtils.getHostnamePort(broker);
+ }
+ Preconditions.checkNotNull(topicId, "TopicID not set");
+
+ this.brokerList = brokerList;
+ this.topicId = topicId;
+ this.schema = serializationSchema;
+ this.partitionerClass = null;
+ this.userDefinedProperties = producerConfig;
+ }
+
+ /**
+ * Creates a KafkaSink for a given topic. The sink produces its input to
+ * the topic.
+ *
+ * @param brokerList
+ * @param topicId
+ * ID of the Kafka topic.
+ * @param serializationSchema
+ * User defined serialization schema.
+ * @param partitioner
+ * User defined partitioner.
+ */
+ public KafkaSink(String brokerList, String topicId, SerializationSchema<IN, byte[]> serializationSchema, SerializableKafkaPartitioner partitioner) {
+ this(brokerList, topicId, serializationSchema);
+ ClosureCleaner.ensureSerializable(partitioner);
+ this.partitioner = partitioner;
+ }
+
+ public KafkaSink(String brokerList,
+ String topicId,
+ SerializationSchema<IN, byte[]> serializationSchema,
+ Class<? extends SerializableKafkaPartitioner> partitioner) {
+ this(brokerList, topicId, serializationSchema);
+ this.partitionerClass = partitioner;
+ }
+
+ /**
+ * Initializes the connection to Kafka.
+ */
+ @Override
+ public void open(Configuration configuration) {
+
+ Properties properties = new Properties();
+
+ properties.put("metadata.broker.list", brokerList);
+ properties.put("request.required.acks", "-1");
+ properties.put("message.send.max.retries", "10");
+
+ properties.put("serializer.class", DefaultEncoder.class.getCanonicalName());
+
+ // this will not be used as the key will not be serialized
+ properties.put("key.serializer.class", DefaultEncoder.class.getCanonicalName());
+
+ for (Map.Entry<Object, Object> propertiesEntry : userDefinedProperties.entrySet()) {
+ properties.put(propertiesEntry.getKey(), propertiesEntry.getValue());
+ }
+
+ if (partitioner != null) {
+ properties.put("partitioner.class", PartitionerWrapper.class.getCanonicalName());
+ // java serialization will do the rest.
+ properties.put(PartitionerWrapper.SERIALIZED_WRAPPER_NAME, partitioner);
+ }
+ if (partitionerClass != null) {
+ properties.put("partitioner.class", partitionerClass);
+ }
+
+ ProducerConfig config = new ProducerConfig(properties);
+
+ try {
+ producer = new Producer<IN, byte[]>(config);
+ } catch (NullPointerException e) {
+ throw new RuntimeException("Cannot connect to Kafka broker " + brokerList, e);
+ }
+ }
+
+ /**
+ * Called when new data arrives to the sink, and forwards it to Kafka.
+ *
+ * @param next
+ * The incoming data
+ */
+ @Override
+ public void invoke(IN next) {
+ byte[] serialized = schema.serialize(next);
+
+ // Sending message without serializable key.
+ producer.send(new KeyedMessage<IN, byte[]>(topicId, null, next, serialized));
+ }
+
+ @Override
+ public void close() {
+ if (producer != null) {
+ producer.close();
+ }
+ }
+
+}
http://git-wip-us.apache.org/repos/asf/flink/blob/9f2f6b7b/flink-staging/flink-streaming/flink-streaming-connectors/flink-connector-kafka/src/main/java/org/apache/flink/streaming/connectors/kafka/SerializableKafkaPartitioner.java
----------------------------------------------------------------------
diff --git a/flink-staging/flink-streaming/flink-streaming-connectors/flink-connector-kafka/src/main/java/org/apache/flink/streaming/connectors/kafka/SerializableKafkaPartitioner.java b/flink-staging/flink-streaming/flink-streaming-connectors/flink-connector-kafka/src/main/java/org/apache/flink/streaming/connectors/kafka/SerializableKafkaPartitioner.java
new file mode 100644
index 0000000..7b9f991
--- /dev/null
+++ b/flink-staging/flink-streaming/flink-streaming-connectors/flink-connector-kafka/src/main/java/org/apache/flink/streaming/connectors/kafka/SerializableKafkaPartitioner.java
@@ -0,0 +1,25 @@
+/*
+ * 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.flink.streaming.connectors.kafka;
+
+import kafka.producer.Partitioner;
+
+import java.io.Serializable;
+
+public interface SerializableKafkaPartitioner extends Serializable, Partitioner {
+
+}
http://git-wip-us.apache.org/repos/asf/flink/blob/9f2f6b7b/flink-staging/flink-streaming/flink-streaming-connectors/flink-connector-kafka/src/main/java/org/apache/flink/streaming/connectors/kafka/api/KafkaSink.java
----------------------------------------------------------------------
diff --git a/flink-staging/flink-streaming/flink-streaming-connectors/flink-connector-kafka/src/main/java/org/apache/flink/streaming/connectors/kafka/api/KafkaSink.java b/flink-staging/flink-streaming/flink-streaming-connectors/flink-connector-kafka/src/main/java/org/apache/flink/streaming/connectors/kafka/api/KafkaSink.java
index ead24f3..c8400a5 100644
--- a/flink-staging/flink-streaming/flink-streaming-connectors/flink-connector-kafka/src/main/java/org/apache/flink/streaming/connectors/kafka/api/KafkaSink.java
+++ b/flink-staging/flink-streaming/flink-streaming-connectors/flink-connector-kafka/src/main/java/org/apache/flink/streaming/connectors/kafka/api/KafkaSink.java
@@ -22,11 +22,11 @@ import org.apache.flink.streaming.util.serialization.SerializationSchema;
/**
* Sink that emits its inputs to a Kafka topic.
*
- * The KafkaSink has been relocated to org.apache.flink.streaming.connectors.KafkaSink.
+ * The KafkaSink has been relocated to org.apache.flink.streaming.connectors.kafka.KafkaSink.
* This class will be removed in future releases of Flink.
*/
@Deprecated
-public class KafkaSink<IN> extends org.apache.flink.streaming.connectors.KafkaSink<IN> {
+public class KafkaSink<IN> extends org.apache.flink.streaming.connectors.kafka.KafkaSink<IN> {
public KafkaSink(String brokerList, String topicId, SerializationSchema<IN, byte[]> serializationSchema) {
super(brokerList, topicId, serializationSchema);
}
http://git-wip-us.apache.org/repos/asf/flink/blob/9f2f6b7b/flink-staging/flink-streaming/flink-streaming-connectors/flink-connector-kafka/src/main/java/org/apache/flink/streaming/connectors/kafka/api/persistent/PersistentKafkaSource.java
----------------------------------------------------------------------
diff --git a/flink-staging/flink-streaming/flink-streaming-connectors/flink-connector-kafka/src/main/java/org/apache/flink/streaming/connectors/kafka/api/persistent/PersistentKafkaSource.java b/flink-staging/flink-streaming/flink-streaming-connectors/flink-connector-kafka/src/main/java/org/apache/flink/streaming/connectors/kafka/api/persistent/PersistentKafkaSource.java
index 4181134..869c44f 100644
--- a/flink-staging/flink-streaming/flink-streaming-connectors/flink-connector-kafka/src/main/java/org/apache/flink/streaming/connectors/kafka/api/persistent/PersistentKafkaSource.java
+++ b/flink-staging/flink-streaming/flink-streaming-connectors/flink-connector-kafka/src/main/java/org/apache/flink/streaming/connectors/kafka/api/persistent/PersistentKafkaSource.java
@@ -18,7 +18,7 @@
package org.apache.flink.streaming.connectors.kafka.api.persistent;
import kafka.consumer.ConsumerConfig;
-import org.apache.flink.streaming.connectors.FlinkKafkaConsumer;
+import org.apache.flink.streaming.connectors.kafka.FlinkKafkaConsumer;
import org.apache.flink.streaming.util.serialization.DeserializationSchema;
http://git-wip-us.apache.org/repos/asf/flink/blob/9f2f6b7b/flink-staging/flink-streaming/flink-streaming-connectors/flink-connector-kafka/src/main/java/org/apache/flink/streaming/connectors/kafka/internals/Fetcher.java
----------------------------------------------------------------------
diff --git a/flink-staging/flink-streaming/flink-streaming-connectors/flink-connector-kafka/src/main/java/org/apache/flink/streaming/connectors/kafka/internals/Fetcher.java b/flink-staging/flink-streaming/flink-streaming-connectors/flink-connector-kafka/src/main/java/org/apache/flink/streaming/connectors/kafka/internals/Fetcher.java
new file mode 100644
index 0000000..4345926
--- /dev/null
+++ b/flink-staging/flink-streaming/flink-streaming-connectors/flink-connector-kafka/src/main/java/org/apache/flink/streaming/connectors/kafka/internals/Fetcher.java
@@ -0,0 +1,83 @@
+/*
+ * 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.flink.streaming.connectors.kafka.internals;
+
+import org.apache.flink.streaming.api.functions.source.SourceFunction;
+import org.apache.flink.streaming.util.serialization.DeserializationSchema;
+import org.apache.kafka.common.TopicPartition;
+
+import java.io.IOException;
+import java.util.List;
+
+/**
+ * A fetcher pulls data from Kafka, from a fix set of partitions.
+ * The fetcher supports "seeking" inside the partitions, i.e., moving to a different offset.
+ */
+public interface Fetcher {
+
+ /**
+ * Set which partitions the fetcher should pull from.
+ *
+ * @param partitions The list of partitions for a topic that the fetcher will pull from.
+ */
+ void setPartitionsToRead(List<TopicPartition> partitions);
+
+ /**
+ * Closes the fetcher. This will stop any operation in the
+ * {@link #run(SourceFunction.SourceContext, DeserializationSchema, long[])} method and eventually
+ * close underlying connections and release all resources.
+ */
+ void close() throws IOException;
+
+ /**
+ * Starts fetch data from Kafka and emitting it into the stream.
+ *
+ * <p>To provide exactly once guarantees, the fetcher needs emit a record and update the update
+ * of the last consumed offset in one atomic operation:</p>
+ * <pre>{@code
+ *
+ * while (running) {
+ * T next = ...
+ * long offset = ...
+ * int partition = ...
+ * synchronized (sourceContext.getCheckpointLock()) {
+ * sourceContext.collect(next);
+ * lastOffsets[partition] = offset;
+ * }
+ * }
+ * }</pre>
+ *
+ * @param sourceContext The source context to emit elements to.
+ * @param valueDeserializer The deserializer to decode the raw values with.
+ * @param lastOffsets The array into which to store the offsets foe which elements are emitted.
+ *
+ * @param <T> The type of elements produced by the fetcher and emitted to the source context.
+ */
+ <T> void run(SourceFunction.SourceContext<T> sourceContext, DeserializationSchema<T> valueDeserializer,
+ long[] lastOffsets) throws Exception;
+
+ /**
+ * Set the next offset to read from for the given partition.
+ * For example, if the partition <i>i</i> offset is set to <i>n</i>, the Fetcher's next result
+ * will be the message with <i>offset=n</i>.
+ *
+ * @param topicPartition The partition for which to seek the offset.
+ * @param offsetToRead To offset to seek to.
+ */
+ void seek(TopicPartition topicPartition, long offsetToRead);
+}
http://git-wip-us.apache.org/repos/asf/flink/blob/9f2f6b7b/flink-staging/flink-streaming/flink-streaming-connectors/flink-connector-kafka/src/main/java/org/apache/flink/streaming/connectors/kafka/internals/LegacyFetcher.java
----------------------------------------------------------------------
diff --git a/flink-staging/flink-streaming/flink-streaming-connectors/flink-connector-kafka/src/main/java/org/apache/flink/streaming/connectors/kafka/internals/LegacyFetcher.java b/flink-staging/flink-streaming/flink-streaming-connectors/flink-connector-kafka/src/main/java/org/apache/flink/streaming/connectors/kafka/internals/LegacyFetcher.java
new file mode 100644
index 0000000..328a96f
--- /dev/null
+++ b/flink-staging/flink-streaming/flink-streaming-connectors/flink-connector-kafka/src/main/java/org/apache/flink/streaming/connectors/kafka/internals/LegacyFetcher.java
@@ -0,0 +1,596 @@
+/*
+ * 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.flink.streaming.connectors.kafka.internals;
+
+import kafka.api.FetchRequestBuilder;
+import kafka.api.OffsetRequest;
+import kafka.api.PartitionOffsetRequestInfo;
+import kafka.common.ErrorMapping;
+import kafka.common.TopicAndPartition;
+import kafka.javaapi.FetchResponse;
+import kafka.javaapi.OffsetResponse;
+import kafka.javaapi.consumer.SimpleConsumer;
+import kafka.javaapi.message.ByteBufferMessageSet;
+import kafka.message.MessageAndOffset;
+
+import org.apache.flink.streaming.api.functions.source.SourceFunction;
+import org.apache.flink.streaming.connectors.kafka.FlinkKafkaConsumer;
+import org.apache.flink.streaming.util.serialization.DeserializationSchema;
+import org.apache.flink.util.StringUtils;
+
+import org.apache.kafka.common.Node;
+import org.apache.kafka.common.PartitionInfo;
+import org.apache.kafka.common.TopicPartition;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+import java.io.IOException;
+import java.nio.ByteBuffer;
+import java.util.ArrayList;
+import java.util.HashMap;
+import java.util.List;
+import java.util.Map;
+import java.util.Properties;
+import java.util.concurrent.atomic.AtomicReference;
+
+import static com.google.common.base.Preconditions.checkNotNull;
+
+/**
+ * This fetcher uses Kafka's low-level API to pull data from a specific
+ * set of partitions and offsets for a certain topic.
+ *
+ * <p>This code is in parts based on the tutorial code for the low-level Kafka consumer.</p>
+ */
+public class LegacyFetcher implements Fetcher {
+
+ private static final Logger LOG = LoggerFactory.getLogger(FlinkKafkaConsumer.class);
+
+ /** The topic from which this fetcher pulls data */
+ private final String topic;
+
+ /** The properties that configure the Kafka connection */
+ private final Properties config;
+
+ /** The task name, to give more readable names to the spawned threads */
+ private final String taskName;
+
+ /** The first error that occurred in a connection thread */
+ private final AtomicReference<Throwable> error;
+
+ /** The partitions that the fetcher should read, with their starting offsets */
+ private Map<TopicPartition, Long> partitionsToRead;
+
+ /** Reference the the thread that executed the run() method. */
+ private volatile Thread mainThread;
+
+ /** Flag to shot the fetcher down */
+ private volatile boolean running = true;
+
+ public LegacyFetcher(String topic, Properties props, String taskName) {
+ this.config = checkNotNull(props, "The config properties cannot be null");
+ this.topic = checkNotNull(topic, "The topic cannot be null");
+ this.taskName = taskName;
+ this.error = new AtomicReference<Throwable>();
+ }
+
+ // ------------------------------------------------------------------------
+ // Fetcher methods
+ // ------------------------------------------------------------------------
+
+ @Override
+ public void setPartitionsToRead(List<TopicPartition> partitions) {
+ partitionsToRead = new HashMap<TopicPartition, Long>(partitions.size());
+ for (TopicPartition tp: partitions) {
+ partitionsToRead.put(tp, FlinkKafkaConsumer.OFFSET_NOT_SET);
+ }
+ }
+
+ @Override
+ public void seek(TopicPartition topicPartition, long offsetToRead) {
+ if (partitionsToRead == null) {
+ throw new IllegalArgumentException("No partitions to read set");
+ }
+ if (!partitionsToRead.containsKey(topicPartition)) {
+ throw new IllegalArgumentException("Can not set offset on a partition (" + topicPartition
+ + ") we are not going to read. Partitions to read " + partitionsToRead);
+ }
+ partitionsToRead.put(topicPartition, offsetToRead);
+ }
+
+ @Override
+ public void close() {
+ // flag needs to be check by the run() method that creates the spawned threads
+ this.running = false;
+
+ // all other cleanup is made by the run method itself
+ }
+
+ @Override
+ public <T> void run(SourceFunction.SourceContext<T> sourceContext,
+ DeserializationSchema<T> valueDeserializer,
+ long[] lastOffsets) throws Exception {
+
+ if (partitionsToRead == null || partitionsToRead.size() == 0) {
+ throw new IllegalArgumentException("No partitions set");
+ }
+
+ // NOTE: This method is needs to always release all resources it acquires
+
+ this.mainThread = Thread.currentThread();
+
+ LOG.info("Reading from partitions " + partitionsToRead + " using the legacy fetcher");
+
+ // get lead broker for each partition
+
+ // NOTE: The kafka client apparently locks itself in an infinite loop sometimes
+ // when it is interrupted, so we run it only in a separate thread.
+ // since it sometimes refuses to shut down, we resort to the admittedly harsh
+ // means of killing the thread after a timeout.
+ PartitionInfoFetcher infoFetcher = new PartitionInfoFetcher(topic, config);
+ infoFetcher.start();
+
+ KillerWatchDog watchDog = new KillerWatchDog(infoFetcher, 60000);
+ watchDog.start();
+
+ final List<PartitionInfo> allPartitionsInTopic = infoFetcher.getPartitions();
+
+ // brokers to fetch partitions from.
+ int fetchPartitionsCount = 0;
+ Map<Node, List<FetchPartition>> fetchBrokers = new HashMap<Node, List<FetchPartition>>();
+
+ for (PartitionInfo partitionInfo : allPartitionsInTopic) {
+ if (partitionInfo.leader() == null) {
+ throw new RuntimeException("Unable to consume partition " + partitionInfo.partition()
+ + " from topic "+partitionInfo.topic()+" because it does not have a leader");
+ }
+
+ for (Map.Entry<TopicPartition, Long> entry : partitionsToRead.entrySet()) {
+ final TopicPartition topicPartition = entry.getKey();
+ final long offset = entry.getValue();
+
+ // check if that partition is for us
+ if (topicPartition.partition() == partitionInfo.partition()) {
+ List<FetchPartition> partitions = fetchBrokers.get(partitionInfo.leader());
+ if (partitions == null) {
+ partitions = new ArrayList<FetchPartition>();
+ fetchBrokers.put(partitionInfo.leader(), partitions);
+ }
+
+ partitions.add(new FetchPartition(topicPartition.partition(), offset));
+ fetchPartitionsCount++;
+
+ }
+ // else this partition is not for us
+ }
+ }
+
+ if (partitionsToRead.size() != fetchPartitionsCount) {
+ throw new RuntimeException(partitionsToRead.size() + " partitions to read, but got only "
+ + fetchPartitionsCount + " partition infos with lead brokers.");
+ }
+
+ // create SimpleConsumers for each broker
+ ArrayList<SimpleConsumerThread<?>> consumers = new ArrayList<SimpleConsumerThread<?>>(fetchBrokers.size());
+
+ for (Map.Entry<Node, List<FetchPartition>> brokerInfo : fetchBrokers.entrySet()) {
+ final Node broker = brokerInfo.getKey();
+ final List<FetchPartition> partitionsList = brokerInfo.getValue();
+
+ FetchPartition[] partitions = partitionsList.toArray(new FetchPartition[partitionsList.size()]);
+
+ SimpleConsumerThread<T> thread = new SimpleConsumerThread<T>(this, config, topic,
+ broker, partitions, sourceContext, valueDeserializer, lastOffsets);
+
+ thread.setName(String.format("SimpleConsumer - %s - broker-%s (%s:%d)",
+ taskName, broker.id(), broker.host(), broker.port()));
+ thread.setDaemon(true);
+ consumers.add(thread);
+ }
+
+ // last check whether we should abort.
+ if (!running) {
+ return;
+ }
+
+ // start all consumer threads
+ for (SimpleConsumerThread<?> t : consumers) {
+ LOG.info("Starting thread {}", t.getName());
+ t.start();
+ }
+
+ // wait until all consumer threads are done, or until we are aborted, or until
+ // an error occurred in one of the fetcher threads
+ try {
+ boolean someConsumersRunning = true;
+ while (running && error.get() == null && someConsumersRunning) {
+ try {
+ // wait for the consumer threads. if an error occurs, we are interrupted
+ for (SimpleConsumerThread<?> t : consumers) {
+ t.join();
+ }
+
+ // safety net
+ someConsumersRunning = false;
+ for (SimpleConsumerThread<?> t : consumers) {
+ someConsumersRunning |= t.isAlive();
+ }
+ }
+ catch (InterruptedException e) {
+ // ignore. we should notice what happened in the next loop check
+ }
+ }
+
+ // make sure any asynchronous error is noticed
+ Throwable error = this.error.get();
+ if (error != null) {
+ throw new Exception(error.getMessage(), error);
+ }
+ }
+ finally {
+ // make sure that in any case (completion, abort, error), all spawned threads are stopped
+ for (SimpleConsumerThread<?> t : consumers) {
+ if (t.isAlive()) {
+ t.cancel();
+ }
+ }
+ }
+ }
+
+ /**
+ * Reports an error from a fetch thread. This will cause the main thread to see this error,
+ * abort, and cancel all other fetch threads.
+ *
+ * @param error The error to report.
+ */
+ void onErrorInFetchThread(Throwable error) {
+ if (this.error.compareAndSet(null, error)) {
+ // we are the first to report an error
+ if (mainThread != null) {
+ mainThread.interrupt();
+ }
+ }
+ }
+
+ // ------------------------------------------------------------------------
+
+ /**
+ * Representation of a partition to fetch.
+ */
+ private static class FetchPartition {
+
+ /** ID of the partition within the topic (0 indexed, as given by Kafka) */
+ int partition;
+
+ /** Offset pointing at the next element to read from that partition. */
+ long nextOffsetToRead;
+
+ FetchPartition(int partition, long nextOffsetToRead) {
+ this.partition = partition;
+ this.nextOffsetToRead = nextOffsetToRead;
+ }
+
+ @Override
+ public String toString() {
+ return "FetchPartition {partition=" + partition + ", offset=" + nextOffsetToRead + '}';
+ }
+ }
+
+ // ------------------------------------------------------------------------
+ // Per broker fetcher
+ // ------------------------------------------------------------------------
+
+ /**
+ * Each broker needs its separate connection. This thread implements the connection to
+ * one broker. The connection can fetch multiple partitions from the broker.
+ *
+ * @param <T> The data type fetched.
+ */
+ private static class SimpleConsumerThread<T> extends Thread {
+
+ private final SourceFunction.SourceContext<T> sourceContext;
+ private final DeserializationSchema<T> valueDeserializer;
+ private final long[] offsetsState;
+
+ private final FetchPartition[] partitions;
+
+ private final Node broker;
+ private final String topic;
+ private final Properties config;
+
+ private final LegacyFetcher owner;
+
+ private SimpleConsumer consumer;
+
+ private volatile boolean running = true;
+
+
+ // exceptions are thrown locally
+ public SimpleConsumerThread(LegacyFetcher owner,
+ Properties config, String topic,
+ Node broker,
+ FetchPartition[] partitions,
+ SourceFunction.SourceContext<T> sourceContext,
+ DeserializationSchema<T> valueDeserializer,
+ long[] offsetsState) {
+ this.owner = owner;
+ this.config = config;
+ this.topic = topic;
+ this.broker = broker;
+ this.partitions = partitions;
+ this.sourceContext = checkNotNull(sourceContext);
+ this.valueDeserializer = checkNotNull(valueDeserializer);
+ this.offsetsState = checkNotNull(offsetsState);
+ }
+
+ @Override
+ public void run() {
+ try {
+ // set up the config values
+ final String clientId = "flink-kafka-consumer-legacy-" + broker.id();
+
+ // these are the actual configuration values of Kafka + their original default values.
+ final int soTimeout = Integer.valueOf(config.getProperty("socket.timeout.ms", "30000"));
+ final int bufferSize = Integer.valueOf(config.getProperty("socket.receive.buffer.bytes", "65536"));
+ final int fetchSize = Integer.valueOf(config.getProperty("fetch.message.max.bytes", "1048576"));
+ final int maxWait = Integer.valueOf(config.getProperty("fetch.wait.max.ms", "100"));
+ final int minBytes = Integer.valueOf(config.getProperty("fetch.min.bytes", "1"));
+
+ // create the Kafka consumer that we actually use for fetching
+ consumer = new SimpleConsumer(broker.host(), broker.port(), soTimeout, bufferSize, clientId);
+
+ // make sure that all partitions have some offsets to start with
+ // those partitions that do not have an offset from a checkpoint need to get
+ // their start offset from ZooKeeper
+
+ List<FetchPartition> partitionsToGetOffsetsFor = new ArrayList<FetchPartition>();
+
+ for (FetchPartition fp : partitions) {
+ if (fp.nextOffsetToRead == FlinkKafkaConsumer.OFFSET_NOT_SET) {
+ // retrieve the offset from the consumer
+ partitionsToGetOffsetsFor.add(fp);
+ }
+ }
+ if (partitionsToGetOffsetsFor.size() > 0) {
+ long timeType;
+ if (config.getProperty("auto.offset.reset", "latest").equals("latest")) {
+ timeType = OffsetRequest.LatestTime();
+ } else {
+ timeType = OffsetRequest.EarliestTime();
+ }
+ getLastOffset(consumer, topic, partitionsToGetOffsetsFor, timeType);
+ LOG.info("No prior offsets found for some partitions in topic {}. Fetched the following start offsets {}",
+ topic, partitionsToGetOffsetsFor);
+ }
+
+ // Now, the actual work starts :-)
+
+ while (running) {
+ FetchRequestBuilder frb = new FetchRequestBuilder();
+ frb.clientId(clientId);
+ frb.maxWait(maxWait);
+ frb.minBytes(minBytes);
+
+ for (FetchPartition fp : partitions) {
+ frb.addFetch(topic, fp.partition, fp.nextOffsetToRead, fetchSize);
+ }
+ kafka.api.FetchRequest fetchRequest = frb.build();
+ LOG.debug("Issuing fetch request {}", fetchRequest);
+
+ FetchResponse fetchResponse;
+ fetchResponse = consumer.fetch(fetchRequest);
+
+ if (fetchResponse.hasError()) {
+ String exception = "";
+ for (FetchPartition fp : partitions) {
+ short code;
+ if ((code = fetchResponse.errorCode(topic, fp.partition)) != ErrorMapping.NoError()) {
+ exception += "\nException for partition " + fp.partition + ": " +
+ StringUtils.stringifyException(ErrorMapping.exceptionFor(code));
+ }
+ }
+ throw new IOException("Error while fetching from broker: " + exception);
+ }
+
+ int messagesInFetch = 0;
+ for (FetchPartition fp : partitions) {
+ final ByteBufferMessageSet messageSet = fetchResponse.messageSet(topic, fp.partition);
+ final int partition = fp.partition;
+
+ for (MessageAndOffset msg : messageSet) {
+ if (running) {
+ messagesInFetch++;
+ if (msg.offset() < fp.nextOffsetToRead) {
+ // we have seen this message already
+ LOG.info("Skipping message with offset " + msg.offset()
+ + " because we have seen messages until " + fp.nextOffsetToRead
+ + " from partition " + fp.partition + " already");
+ continue;
+ }
+
+ ByteBuffer payload = msg.message().payload();
+ byte[] valueByte = new byte[payload.remaining()];
+ payload.get(valueByte);
+
+ final T value = valueDeserializer.deserialize(valueByte);
+ final long offset = msg.offset();
+
+ synchronized (sourceContext.getCheckpointLock()) {
+ sourceContext.collect(value);
+ offsetsState[partition] = offset;
+ }
+
+ // advance offset for the next request
+ fp.nextOffsetToRead = offset + 1;
+ }
+ else {
+ // no longer running
+ return;
+ }
+ }
+ }
+ LOG.debug("This fetch contained {} messages", messagesInFetch);
+ }
+ }
+ catch (Throwable t) {
+ // report to the main thread
+ owner.onErrorInFetchThread(t);
+ }
+ finally {
+ // end of run loop. close connection to consumer
+ if (consumer != null) {
+ // closing the consumer should not fail the program
+ try {
+ consumer.close();
+ }
+ catch (Throwable t) {
+ LOG.error("Error while closing the Kafka simple consumer", t);
+ }
+ }
+ }
+ }
+
+ /**
+ * Cancels this fetch thread. The thread will release all resources and terminate.
+ */
+ public void cancel() {
+ this.running = false;
+
+ // interrupt whatever the consumer is doing
+ if (consumer != null) {
+ consumer.close();
+ }
+
+ this.interrupt();
+ }
+
+ /**
+ * Request latest offsets for a set of partitions, via a Kafka consumer.
+ *
+ * @param consumer The consumer connected to lead broker
+ * @param topic The topic name
+ * @param partitions The list of partitions we need offsets for
+ * @param whichTime The type of time we are requesting. -1 and -2 are special constants (See OffsetRequest)
+ */
+ private static void getLastOffset(SimpleConsumer consumer, String topic, List<FetchPartition> partitions, long whichTime) {
+
+ Map<TopicAndPartition, PartitionOffsetRequestInfo> requestInfo = new HashMap<TopicAndPartition, PartitionOffsetRequestInfo>();
+ for (FetchPartition fp: partitions) {
+ TopicAndPartition topicAndPartition = new TopicAndPartition(topic, fp.partition);
+ requestInfo.put(topicAndPartition, new PartitionOffsetRequestInfo(whichTime, 1));
+ }
+
+ kafka.javaapi.OffsetRequest request = new kafka.javaapi.OffsetRequest(requestInfo, kafka.api.OffsetRequest.CurrentVersion(), consumer.clientId());
+ OffsetResponse response = consumer.getOffsetsBefore(request);
+
+ if (response.hasError()) {
+ String exception = "";
+ for (FetchPartition fp: partitions) {
+ short code;
+ if ( (code=response.errorCode(topic, fp.partition)) != ErrorMapping.NoError()) {
+ exception += "\nException for partition "+fp.partition+": "+ StringUtils.stringifyException(ErrorMapping.exceptionFor(code));
+ }
+ }
+ throw new RuntimeException("Unable to get last offset for topic " + topic + " and partitions " + partitions
+ + ". " + exception);
+ }
+
+ for (FetchPartition fp: partitions) {
+ // the resulting offset is the next offset we are going to read
+ // for not-yet-consumed partitions, it is 0.
+ fp.nextOffsetToRead = response.offsets(topic, fp.partition)[0];
+ }
+ }
+ }
+
+ private static class PartitionInfoFetcher extends Thread {
+
+ private final String topic;
+ private final Properties properties;
+
+ private volatile List<PartitionInfo> result;
+ private volatile Throwable error;
+
+
+ PartitionInfoFetcher(String topic, Properties properties) {
+ this.topic = topic;
+ this.properties = properties;
+ }
+
+ @Override
+ public void run() {
+ try {
+ result = FlinkKafkaConsumer.getPartitionsForTopic(topic, properties);
+ }
+ catch (Throwable t) {
+ this.error = t;
+ }
+ }
+
+ public List<PartitionInfo> getPartitions() throws Exception {
+ try {
+ this.join();
+ }
+ catch (InterruptedException e) {
+ throw new Exception("Partition fetching was cancelled before completion");
+ }
+
+ if (error != null) {
+ throw new Exception("Failed to fetch partitions for topic " + topic, error);
+ }
+ if (result != null) {
+ return result;
+ }
+ throw new Exception("Partition fetching failed");
+ }
+ }
+
+ private static class KillerWatchDog extends Thread {
+
+ private final Thread toKill;
+ private final long timeout;
+
+ private KillerWatchDog(Thread toKill, long timeout) {
+ super("KillerWatchDog");
+ setDaemon(true);
+
+ this.toKill = toKill;
+ this.timeout = timeout;
+ }
+
+ @SuppressWarnings("deprecation")
+ @Override
+ public void run() {
+ final long deadline = System.currentTimeMillis() + timeout;
+ long now;
+
+ while (toKill.isAlive() && (now = System.currentTimeMillis()) < deadline) {
+ try {
+ toKill.join(deadline - now);
+ }
+ catch (InterruptedException e) {
+ // ignore here, our job is important!
+ }
+ }
+
+ // this is harsh, but this watchdog is a last resort
+ if (toKill.isAlive()) {
+ toKill.stop();
+ }
+ }
+ }
+}
http://git-wip-us.apache.org/repos/asf/flink/blob/9f2f6b7b/flink-staging/flink-streaming/flink-streaming-connectors/flink-connector-kafka/src/main/java/org/apache/flink/streaming/connectors/kafka/internals/OffsetHandler.java
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diff --git a/flink-staging/flink-streaming/flink-streaming-connectors/flink-connector-kafka/src/main/java/org/apache/flink/streaming/connectors/kafka/internals/OffsetHandler.java b/flink-staging/flink-streaming/flink-streaming-connectors/flink-connector-kafka/src/main/java/org/apache/flink/streaming/connectors/kafka/internals/OffsetHandler.java
new file mode 100644
index 0000000..2a82561
--- /dev/null
+++ b/flink-staging/flink-streaming/flink-streaming-connectors/flink-connector-kafka/src/main/java/org/apache/flink/streaming/connectors/kafka/internals/OffsetHandler.java
@@ -0,0 +1,58 @@
+/*
+ * 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.flink.streaming.connectors.kafka.internals;
+
+
+import org.apache.kafka.common.TopicPartition;
+
+import java.io.IOException;
+import java.util.List;
+import java.util.Map;
+
+/**
+ * The offset handler is responsible for locating the initial partition offsets
+ * where the source should start reading, as well as committing offsets from completed
+ * checkpoints.
+ */
+public interface OffsetHandler {
+
+ /**
+ * Commits the given offset for the partitions. May commit the offsets to the Kafka broker,
+ * or to ZooKeeper, based on its configured behavior.
+ *
+ * @param offsetsToCommit The offset to commit, per partition.
+ */
+ void commit(Map<TopicPartition, Long> offsetsToCommit) throws Exception;
+
+ /**
+ * Positions the given fetcher to the initial read offsets where the stream consumption
+ * will start from.
+ *
+ * @param partitions The partitions for which to seeks the fetcher to the beginning.
+ * @param fetcher The fetcher that will pull data from Kafka and must be positioned.
+ */
+ void seekFetcherToInitialOffsets(List<TopicPartition> partitions, Fetcher fetcher) throws Exception;
+
+ /**
+ * Closes the offset handler, releasing all resources.
+ *
+ * @throws IOException Thrown, if the closing fails.
+ */
+ void close() throws IOException;
+}
http://git-wip-us.apache.org/repos/asf/flink/blob/9f2f6b7b/flink-staging/flink-streaming/flink-streaming-connectors/flink-connector-kafka/src/main/java/org/apache/flink/streaming/connectors/kafka/internals/PartitionerWrapper.java
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diff --git a/flink-staging/flink-streaming/flink-streaming-connectors/flink-connector-kafka/src/main/java/org/apache/flink/streaming/connectors/kafka/internals/PartitionerWrapper.java b/flink-staging/flink-streaming/flink-streaming-connectors/flink-connector-kafka/src/main/java/org/apache/flink/streaming/connectors/kafka/internals/PartitionerWrapper.java
new file mode 100644
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+++ b/flink-staging/flink-streaming/flink-streaming-connectors/flink-connector-kafka/src/main/java/org/apache/flink/streaming/connectors/kafka/internals/PartitionerWrapper.java
@@ -0,0 +1,49 @@
+/*
+ * 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.flink.streaming.connectors.kafka.internals;
+
+import kafka.producer.Partitioner;
+import kafka.utils.VerifiableProperties;
+
+/**
+ * Hacky wrapper to send an object instance through a Properties - map.
+ *
+ * This works as follows:
+ * The recommended way of creating a KafkaSink is specifying a classname for the partitioner.
+ *
+ * Otherwise (if the user gave a (serializable) class instance), we give Kafka the PartitionerWrapper class of Flink.
+ * This is set in the key-value (java.util.Properties) map.
+ * In addition to that, we use the Properties.put(Object, Object) to store the instance of the (serializable).
+ * This is a hack because the put() method is called on the underlying Hashmap.
+ *
+ * This PartitionerWrapper is called with the Properties. From there, we extract the wrapped Partitioner instance.
+ *
+ * The serializable PartitionerWrapper is serialized into the Properties Hashmap and also deserialized from there.
+ */
+public class PartitionerWrapper implements Partitioner {
+ public final static String SERIALIZED_WRAPPER_NAME = "flink.kafka.wrapper.serialized";
+
+ private Partitioner wrapped;
+ public PartitionerWrapper(VerifiableProperties properties) {
+ wrapped = (Partitioner) properties.props().get(SERIALIZED_WRAPPER_NAME);
+ }
+
+ @Override
+ public int partition(Object value, int numberOfPartitions) {
+ return wrapped.partition(value, numberOfPartitions);
+ }
+}
http://git-wip-us.apache.org/repos/asf/flink/blob/9f2f6b7b/flink-staging/flink-streaming/flink-streaming-connectors/flink-connector-kafka/src/main/java/org/apache/flink/streaming/connectors/kafka/internals/ZooKeeperStringSerializer.java
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diff --git a/flink-staging/flink-streaming/flink-streaming-connectors/flink-connector-kafka/src/main/java/org/apache/flink/streaming/connectors/kafka/internals/ZooKeeperStringSerializer.java b/flink-staging/flink-streaming/flink-streaming-connectors/flink-connector-kafka/src/main/java/org/apache/flink/streaming/connectors/kafka/internals/ZooKeeperStringSerializer.java
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+/*
+ * 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.flink.streaming.connectors.kafka.internals;
+
+import org.I0Itec.zkclient.serialize.ZkSerializer;
+
+import java.nio.charset.Charset;
+
+/**
+ * Simple ZooKeeper serializer for Strings.
+ */
+public class ZooKeeperStringSerializer implements ZkSerializer {
+
+ private static final Charset CHARSET = Charset.forName("UTF-8");
+
+ @Override
+ public byte[] serialize(Object data) {
+ if (data instanceof String) {
+ return ((String) data).getBytes(CHARSET);
+ }
+ else {
+ throw new IllegalArgumentException("ZooKeeperStringSerializer can only serialize strings.");
+ }
+ }
+
+ @Override
+ public Object deserialize(byte[] bytes) {
+ if (bytes == null) {
+ return null;
+ }
+ else {
+ return new String(bytes, CHARSET);
+ }
+ }
+}
http://git-wip-us.apache.org/repos/asf/flink/blob/9f2f6b7b/flink-staging/flink-streaming/flink-streaming-connectors/flink-connector-kafka/src/main/java/org/apache/flink/streaming/connectors/kafka/internals/ZookeeperOffsetHandler.java
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diff --git a/flink-staging/flink-streaming/flink-streaming-connectors/flink-connector-kafka/src/main/java/org/apache/flink/streaming/connectors/kafka/internals/ZookeeperOffsetHandler.java b/flink-staging/flink-streaming/flink-streaming-connectors/flink-connector-kafka/src/main/java/org/apache/flink/streaming/connectors/kafka/internals/ZookeeperOffsetHandler.java
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+/*
+ * 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.flink.streaming.connectors.kafka.internals;
+
+import kafka.common.TopicAndPartition;
+import kafka.utils.ZKGroupTopicDirs;
+import kafka.utils.ZkUtils;
+
+import org.I0Itec.zkclient.ZkClient;
+import org.apache.flink.streaming.connectors.kafka.FlinkKafkaConsumer;
+import org.apache.kafka.clients.consumer.ConsumerConfig;
+import org.apache.kafka.common.TopicPartition;
+import org.apache.zookeeper.data.Stat;
+
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+import scala.Option;
+
+import java.io.IOException;
+import java.util.List;
+import java.util.Map;
+import java.util.Properties;
+
+public class ZookeeperOffsetHandler implements OffsetHandler {
+
+ private static final Logger LOG = LoggerFactory.getLogger(ZookeeperOffsetHandler.class);
+
+ private static final long OFFSET_NOT_SET = FlinkKafkaConsumer.OFFSET_NOT_SET;
+
+
+ private final ZkClient zkClient;
+
+ private final String groupId;
+
+
+ public ZookeeperOffsetHandler(Properties props) {
+ this.groupId = props.getProperty(ConsumerConfig.GROUP_ID_CONFIG);
+
+ if (this.groupId == null) {
+ throw new IllegalArgumentException("Required property '"
+ + ConsumerConfig.GROUP_ID_CONFIG + "' has not been set");
+ }
+
+ String zkConnect = props.getProperty("zookeeper.connect");
+ if (zkConnect == null) {
+ throw new IllegalArgumentException("Required property 'zookeeper.connect' has not been set");
+ }
+
+ zkClient = new ZkClient(zkConnect,
+ Integer.valueOf(props.getProperty("zookeeper.session.timeout.ms", "6000")),
+ Integer.valueOf(props.getProperty("zookeeper.connection.timeout.ms", "6000")),
+ new ZooKeeperStringSerializer());
+ }
+
+
+ @Override
+ public void commit(Map<TopicPartition, Long> offsetsToCommit) {
+ for (Map.Entry<TopicPartition, Long> entry : offsetsToCommit.entrySet()) {
+ TopicPartition tp = entry.getKey();
+ long offset = entry.getValue();
+
+ if (offset >= 0) {
+ setOffsetInZooKeeper(zkClient, groupId, tp.topic(), tp.partition(), offset);
+ }
+ }
+ }
+
+ @Override
+ public void seekFetcherToInitialOffsets(List<TopicPartition> partitions, Fetcher fetcher) {
+ for (TopicPartition tp : partitions) {
+ long offset = getOffsetFromZooKeeper(zkClient, groupId, tp.topic(), tp.partition());
+
+ if (offset != OFFSET_NOT_SET) {
+ LOG.info("Offset for partition {} was set to {} in ZooKeeper. Seeking fetcher to that position.",
+ tp.partition(), offset);
+
+ // the offset in Zookeeper was the last read offset, seek is accepting the next-to-read-offset.
+ fetcher.seek(tp, offset + 1);
+ }
+ }
+ }
+
+ @Override
+ public void close() throws IOException {
+ zkClient.close();
+ }
+
+ // ------------------------------------------------------------------------
+ // Communication with Zookeeper
+ // ------------------------------------------------------------------------
+
+ public static void setOffsetInZooKeeper(ZkClient zkClient, String groupId, String topic, int partition, long offset) {
+ TopicAndPartition tap = new TopicAndPartition(topic, partition);
+ ZKGroupTopicDirs topicDirs = new ZKGroupTopicDirs(groupId, tap.topic());
+ ZkUtils.updatePersistentPath(zkClient, topicDirs.consumerOffsetDir() + "/" + tap.partition(), Long.toString(offset));
+ }
+
+ public static long getOffsetFromZooKeeper(ZkClient zkClient, String groupId, String topic, int partition) {
+ TopicAndPartition tap = new TopicAndPartition(topic, partition);
+ ZKGroupTopicDirs topicDirs = new ZKGroupTopicDirs(groupId, tap.topic());
+
+ scala.Tuple2<Option<String>, Stat> data = ZkUtils.readDataMaybeNull(zkClient,
+ topicDirs.consumerOffsetDir() + "/" + tap.partition());
+
+ if (data._1().isEmpty()) {
+ return OFFSET_NOT_SET;
+ } else {
+ return Long.valueOf(data._1().get());
+ }
+ }
+}