HDFS

This guide shows you how to import data from HDFS.

You can enable the Hadoop DFS using the plugin pinot-hdfs. In the controller or server, add the config -

-Dplugins.dir=/opt/pinot/plugins -Dplugins.include=pinot-hdfs

HDFS implementation provides the following options -

  • hadoop.conf.path : Absolute path of the directory containing hadoop XML configuration files such as hdfs-site.xml, core-site.xml .

  • hadoop.write.checksum : create checksum while pushing an object. Default is false

  • hadoop.kerberos.principle

  • hadoop.kerberos.keytab

Each of these properties should be prefixed by pinot.[node].storage.factory.class.hdfs. where node is either controller or server depending on the config

The kerberos configs should be used only if your Hadoop installation is secured with Kerberos. Please check Hadoop Kerberos guide on how to generate Kerberos security identification.

You will also need to provide proper Hadoop dependencies jars from your Hadoop installation to your Pinot startup scripts.

Push HDFS segment to Pinot Controller

To push HDFS segment files to Pinot controller, you just need to ensure you have proper Hadoop configuration as we mentioned in the previous part. Then your remote segment creation/push job can send the HDFS path of your newly created segment files to the Pinot Controller and let it download the files.

For example, the following curl requests to Controller will notify it to download segment files to the proper table:

curl -X POST -H "UPLOAD_TYPE:URI" -H "DOWNLOAD_URI:hdfs://nameservice1/hadoop/path/to/segment/file.

Examples

Job spec

executionFrameworkSpec:
name: 'standalone'
segmentGenerationJobRunnerClassName: 'org.apache.pinot.plugin.ingestion.batch.standalone.SegmentGenerationJobRunner'
segmentTarPushJobRunnerClassName: 'org.apache.pinot.plugin.ingestion.batch.standalone.SegmentTarPushJobRunner'
segmentUriPushJobRunnerClassName: 'org.apache.pinot.plugin.ingestion.batch.standalone.SegmentUriPushJobRunner'
jobType: SegmentCreationAndTarPush
inputDirURI: 'hdfs:///path/to/input/directory/'
outputDirURI: 'hdfs:///path/to/output/directory/'
overwriteOutput: true
pinotFSSpecs:
- scheme: hdfs
className: org.apache.pinot.plugin.filesystem.HadoopPinotFS
configs:
hadoop.conf.path: 'path/to/conf/directory/'
recordReaderSpec:
dataFormat: 'csv'
className: 'org.apache.pinot.plugin.inputformat.csv.CSVRecordReader'
configClassName: 'org.apache.pinot.plugin.inputformat.csv.CSVRecordReaderConfig'
tableSpec:
tableName: 'students'
pinotClusterSpecs:
- controllerURI: 'http://localhost:9000'

Controller config

controller.data.dir=hdfs://path/to/data/directory/
controller.local.temp.dir=/path/to/local/temp/directory
controller.enable.split.commit=true
pinot.controller.storage.factory.class.hdfs=org.apache.pinot.plugin.filesystem.HadoopPinotFS
pinot.controller.storage.factory.hdfs.hadoop.conf.path=path/to/conf/directory/
pinot.controller.segment.fetcher.protocols=file,http,hdfs
pinot.controller.segment.fetcher.adl.class=org.apache.pinot.common.utils.fetcher.PinotFSSegmentFetcher
pinot.controller.segment.fetcher.hdfs.hadoop.kerberos.principle=`<your kerberos principal>
pinot.controller.segment.fetcher.hdfs.hadoop.kerberos.keytab=`<your kerberos keytab>

Server config

pinot.server.instance.enable.split.commit=true
pinot.server.storage.factory.class.hdfs=org.apache.pinot.plugin.filesystem.HadoopPinotFS
pinot.server.storage.factory.hdfs.hadoop.conf.path=path/to/conf/directory/
pinot.server.segment.fetcher.protocols=file,http,hdfs
pinot.server.segment.fetcher.hdfs.class=org.apache.pinot.common.utils.fetcher.PinotFSSegmentFetcher
pinot.server.segment.fetcher.hdfs.hadoop.kerberos.principle=`<your kerberos principal>
pinot.server.segment.fetcher.hdfs.hadoop.kerberos.keytab=`<your kerberos keytab>