samza-kafka/src/main/scala/org/apache/samza/checkpoint/kafka/KafkaCheckpointManagerFactory.scala

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 * to you under the Apache License, Version 2.0 (the
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package org.apache.samza.checkpoint.kafka

import org.apache.samza.SamzaException
import org.apache.samza.checkpoint.{CheckpointManager, CheckpointManagerFactory}
import org.apache.samza.config._
import org.apache.samza.metrics.MetricsRegistry
import org.apache.samza.system.{StreamSpec, SystemFactory}
import org.apache.samza.system.kafka.KafkaStreamSpec
import org.apache.samza.util.ScalaJavaUtil.JavaOptionals
import org.apache.samza.util.{KafkaUtil, Logging, _}

class KafkaCheckpointManagerFactory extends CheckpointManagerFactory with Logging {

  def getCheckpointManager(config: Config, registry: MetricsRegistry): CheckpointManager = {
    val jobConfig = new JobConfig(config)
    val jobName = JavaOptionals.toRichOptional(jobConfig.getName).toOption
      .getOrElse(throw new SamzaException("Missing job name in configs"))
    val jobId = jobConfig.getJobId

    val kafkaConfig = new KafkaConfig(config)
    val checkpointSystemName = kafkaConfig.getCheckpointSystem.getOrElse(
      throw new SamzaException("No system defined for Kafka's checkpoint manager."))

    val systemConfig = new SystemConfig(config)
    val checkpointSystemFactoryName = JavaOptionals.toRichOptional(systemConfig.getSystemFactory(checkpointSystemName))
      .toOption
      .getOrElse(throw new SamzaException("Missing configuration: " + SystemConfig.SYSTEM_FACTORY_FORMAT format checkpointSystemName))

    val checkpointSystemFactory = ReflectionUtil.getObj(checkpointSystemFactoryName, classOf[SystemFactory])
    val checkpointTopic = KafkaUtil.getCheckpointTopic(jobName, jobId, config)

    info(s"Creating a KafkaCheckpointManager to consume from $checkpointTopic")
    val checkpointSpec = KafkaStreamSpec.fromSpec(StreamSpec.createCheckpointStreamSpec(checkpointTopic, checkpointSystemName))
        .copyWithReplicationFactor(kafkaConfig.getCheckpointReplicationFactor.get.toInt)
        .copyWithProperties(kafkaConfig.getCheckpointTopicProperties)

    new KafkaCheckpointManager(checkpointSpec, checkpointSystemFactory, jobConfig.failOnCheckpointValidation, config,
      new NoOpMetricsRegistry)
  }
}