Examples with FetchRequest kafka.api.FetchRequest used on opensource projects

Example 6 with FetchRequest

use of kafka.api.FetchRequest in project bagheera by mozilla-metrics.

the class ProducerTest method countMessages.

private int countMessages() throws InvalidProtocolBufferException {
    SimpleConsumer consumer = new SimpleConsumer("localhost", KAFKA_BROKER_PORT, 100, 1024);
    long offset = 0l;
    int messageCount = 0;
    for (int i = 0; i < BATCH_SIZE; i++) {
        ByteBufferMessageSet messageSet = consumer.fetch(new FetchRequest(KAFKA_TOPIC, 0, offset, 1024));
        Iterator<MessageAndOffset> iterator = messageSet.iterator();
        MessageAndOffset msgAndOff;
        while (iterator.hasNext()) {
            messageCount++;
            msgAndOff = iterator.next();
            offset = msgAndOff.offset();
            Message message2 = msgAndOff.message();
            BagheeraMessage bmsg = BagheeraMessage.parseFrom(ByteString.copyFrom(message2.payload()));
            String payload = new String(bmsg.getPayload().toByteArray());
            System.out.println(String.format("Message %d @%d: %s", messageCount, offset, payload));
        }
    }
    consumer.close();
    return messageCount;
}

Example 7 with FetchRequest

use of kafka.api.FetchRequest in project voltdb by VoltDB.

the class KafkaTopicPartitionImporter method accept.

@Override
protected void accept() {
    info(null, "Starting partition fetcher for " + m_topicAndPartition);
    long submitCount = 0;
    PendingWorkTracker callbackTracker = new PendingWorkTracker();
    Formatter formatter = m_config.getFormatterBuilder().create();
    try {
        //Start with the starting leader.
        resetLeader();
        int sleepCounter = 1;
        while (shouldRun()) {
            if (m_currentOffset.get() < 0) {
                getOffsetCoordinator();
                if (m_offsetManager.get() == null) {
                    sleepCounter = backoffSleep(sleepCounter);
                    continue;
                }
                long lastOffset = getLastOffset();
                if (lastOffset == -1) {
                    sleepCounter = backoffSleep(sleepCounter);
                    continue;
                }
                m_gapTracker.resetTo(lastOffset);
                m_lastCommittedOffset = lastOffset;
                m_currentOffset.set(lastOffset);
                if (m_currentOffset.get() < 0) {
                    //If we dont know the offset get it backoff if we fail.
                    sleepCounter = backoffSleep(sleepCounter);
                    info(null, "No valid offset found for " + m_topicAndPartition);
                    continue;
                }
                info(null, "Starting offset for " + m_topicAndPartition + " is " + m_currentOffset.get());
            }
            long currentFetchCount = 0;
            //Build fetch request of we have a valid offset and not too many are pending.
            FetchRequest req = m_fetchRequestBuilder.addFetch(m_topicAndPartition.topic(), m_topicAndPartition.partition(), m_currentOffset.get(), m_config.getFetchSize()).build();
            FetchResponse fetchResponse = null;
            try {
                fetchResponse = m_consumer.fetch(req);
                if (fetchResponse == null) {
                    sleepCounter = backoffSleep(sleepCounter);
                    continue;
                }
            } catch (Exception ex) {
                rateLimitedLog(Level.WARN, ex, "Failed to fetch from " + m_topicAndPartition);
                //See if its network error and find new leader for this partition.
                if (ex instanceof IOException) {
                    resetLeader();
                    //find leader in resetLeader would sleep and backoff
                    continue;
                }
                sleepCounter = backoffSleep(sleepCounter);
                continue;
            }
            if (fetchResponse.hasError()) {
                // Something went wrong!
                short code = fetchResponse.errorCode(m_topicAndPartition.topic(), m_topicAndPartition.partition());
                warn(ErrorMapping.exceptionFor(code), "Failed to fetch messages for %s", m_topicAndPartition);
                sleepCounter = backoffSleep(sleepCounter);
                if (code == ErrorMapping.OffsetOutOfRangeCode()) {
                    // We asked for an invalid offset. For simple case ask for the last element to reset
                    info(null, "Invalid offset requested for " + m_topicAndPartition);
                    getOffsetCoordinator();
                    m_currentOffset.set(-1L);
                    continue;
                }
                resetLeader();
                continue;
            }
            sleepCounter = 1;
            for (MessageAndOffset messageAndOffset : fetchResponse.messageSet(m_topicAndPartition.topic(), m_topicAndPartition.partition())) {
                //You may be catchin up so dont sleep.
                currentFetchCount++;
                long currentOffset = messageAndOffset.offset();
                //if currentOffset is less means we have already pushed it and also check pending queue.
                if (currentOffset < m_currentOffset.get()) {
                    continue;
                }
                ByteBuffer payload = messageAndOffset.message().payload();
                Object[] params = null;
                try {
                    m_gapTracker.submit(messageAndOffset.nextOffset());
                    params = formatter.transform(payload);
                    Invocation invocation = new Invocation(m_config.getProcedure(), params);
                    TopicPartitionInvocationCallback cb = new TopicPartitionInvocationCallback(messageAndOffset.offset(), messageAndOffset.nextOffset(), callbackTracker, m_gapTracker, m_dead, m_pauseOffset);
                    if (!noTransaction) {
                        if (callProcedure(invocation, cb)) {
                            callbackTracker.produceWork();
                        } else {
                            if (isDebugEnabled()) {
                                debug(null, "Failed to process Invocation possibly bad data: " + Arrays.toString(params));
                            }
                            m_gapTracker.commit(messageAndOffset.nextOffset());
                        }
                    }
                } catch (FormatException e) {
                    rateLimitedLog(Level.WARN, e, "Failed to tranform data: %s", Arrays.toString(params));
                    m_gapTracker.commit(messageAndOffset.nextOffset());
                }
                submitCount++;
                m_currentOffset.set(messageAndOffset.nextOffset());
                if (!shouldRun()) {
                    break;
                }
            }
            if (!shouldRun()) {
                break;
            }
            //wait to fetch more if we read nothing last time.
            if (currentFetchCount == 0) {
                try {
                    Thread.sleep(m_waitSleepMs);
                } catch (InterruptedException ie) {
                }
            }
            if (shouldCommit()) {
                commitOffset(false);
            }
        }
    } catch (Exception ex) {
        error(ex, "Failed to start topic partition fetcher for " + m_topicAndPartition);
    } finally {
        final boolean usePausedOffset = m_pauseOffset.get() != -1;
        boolean skipCommit = false;
        if (usePausedOffset) {
            // Paused offset is not guaranteed reliable until all callbacks have been called.
            if (callbackTracker.waitForWorkToFinish() == false) {
                if (m_pauseOffset.get() < m_lastCommittedOffset) {
                    warn(null, "Committing paused offset even though a timeout occurred waiting for pending stored procedures to finish.");
                } else {
                    warn(null, "Refusing to commit paused offset because a timeout occurred waiting for pending stored procedures to finish.");
                    skipCommit = true;
                }
            }
        }
        if (skipCommit == false) {
            // Force a commit. Paused offset will be re-acquired if needed.
            commitOffset(usePausedOffset);
        }
        KafkaStreamImporterConfig.closeConsumer(m_consumer);
        m_consumer = null;
        BlockingChannel channel = m_offsetManager.getAndSet(null);
        if (channel != null) {
            try {
                channel.disconnect();
            } catch (Exception ignoreIt) {
            }
        }
    }
    m_dead.compareAndSet(false, true);
    info(null, "Partition fetcher stopped for " + m_topicAndPartition + " Last commit point is: " + m_lastCommittedOffset + " Callback Rcvd: " + callbackTracker.getCallbackCount() + " Submitted: " + submitCount);
}

Example 8 with FetchRequest

use of kafka.api.FetchRequest in project cdap by caskdata.

the class KafkaConsumer method fetchMessageSet.

private ByteBufferMessageSet fetchMessageSet(long fetchOffset) throws OffsetOutOfRangeException {
    Preconditions.checkArgument(fetchOffset >= 0, String.format("Illegal fetch offset %d", fetchOffset));
    int failureCount = 0;
    while (true) {
        SimpleConsumer consumer = getConsumer();
        FetchRequest req = new FetchRequestBuilder().clientId(clientName).addFetch(topic, partition, fetchOffset, BUFFER_SIZE_BYTES).maxWait(fetchTimeoutMs).build();
        FetchResponse fetchResponse = consumer.fetch(req);
        if (!fetchResponse.hasError()) {
            return fetchResponse.messageSet(topic, partition);
        }
        short errorCode = fetchResponse.errorCode(topic, partition);
        if (++failureCount >= MAX_KAFKA_FETCH_RETRIES) {
            throw new RuntimeException(String.format("Error fetching data from broker %s:%d for topic %s, partition %d. Error code: %d", consumer.host(), consumer.port(), topic, partition, errorCode));
        }
        LOG.warn("Error fetching data from broker {}:{} for topic {}, partition {}. Error code: {}", consumer.host(), consumer.port(), topic, partition, errorCode);
        if (errorCode == ErrorMapping.OffsetOutOfRangeCode()) {
            throw new OffsetOutOfRangeException(String.format("Requested offset %d is out of range for topic %s partition %d", fetchOffset, topic, partition));
        }
        closeConsumer();
    }
}

Example 9 with FetchRequest

use of kafka.api.FetchRequest in project cdap by caskdata.

the class KafkaUtil method fetchMessages.

/**
   * Fetches messages from the given topic, partition and offset using the provided {@link SimpleConsumer}.
   *
   * @return A {@link ByteBufferMessageSet} of the given topic, partition for messages fetched
   *
   * @throws OffsetOutOfRangeException if the given offset is out of range.
   * @throws NotLeaderForPartitionException if the broker that the consumer is talking to is not the leader
   *                                        for the given topic and partition.
   * @throws UnknownTopicOrPartitionException if the topic or partition is not known by the Kafka server
   * @throws UnknownServerException if the Kafka server responded with error.
   */
public static ByteBufferMessageSet fetchMessages(SimpleConsumer consumer, String topic, int partition, int fetchSize, long requestOffset) throws KafkaException {
    FetchRequest req = new FetchRequestBuilder().clientId(consumer.clientId()).addFetch(topic, partition, requestOffset, fetchSize).build();
    FetchResponse fetchResponse = consumer.fetch(req);
    if (fetchResponse.hasError()) {
        throw Errors.forCode(fetchResponse.errorCode(topic, partition)).exception();
    }
    return fetchResponse.messageSet(topic, partition);
}