Examples with DatasetStatePersistor co.cask.cdap.api.dataset.lib.DatasetStatePersistor used on opensource projects

Example 1 with DatasetStatePersistor

use of co.cask.cdap.api.dataset.lib.DatasetStatePersistor in project cdap by caskdata.

the class PartitionBatchInput method setInput.

/**
 * Used from the initialize method of the implementing batch job to configure as input a PartitionedFileSet that has
 * specified a set of {@link Partition}s of a {@link PartitionedFileSet} to be processed by the run of the batch job.
 * It does this by reading back the previous state, determining the new partitions to read, computing the new
 * state, and persisting this new state. It then configures this dataset as input to the mapreduce context that is
 * passed in.
 *
 * @param mapreduceContext MapReduce context used to access the PartitionedFileSet, and on which the input is
 *                         configured
 * @param partitionedFileSetName the name of the {@link PartitionedFileSet} to consume partitions from
 * @param statePersistor a {@link DatasetStatePersistor} responsible for defining how the partition consumer state is
 *                       managed
 * @param consumerConfiguration defines parameters for the partition consumption
 * @return a BatchPartitionCommitter used to persist the state of the partition consumer
 */
public static BatchPartitionCommitter setInput(MapReduceContext mapreduceContext, String partitionedFileSetName, DatasetStatePersistor statePersistor, ConsumerConfiguration consumerConfiguration) {
    PartitionedFileSet partitionedFileSet = mapreduceContext.getDataset(partitionedFileSetName);
    final PartitionConsumer partitionConsumer = new ConcurrentPartitionConsumer(partitionedFileSet, new DelegatingStatePersistor(mapreduceContext, statePersistor), consumerConfiguration);
    final List<PartitionDetail> consumedPartitions = partitionConsumer.consumePartitions().getPartitions();
    Map<String, String> arguments = new HashMap<>();
    PartitionedFileSetArguments.addInputPartitions(arguments, consumedPartitions);
    mapreduceContext.addInput(Input.ofDataset(partitionedFileSetName, arguments));
    return succeeded -> partitionConsumer.onFinish(consumedPartitions, succeeded);
}