Description

An extension to FsDataWriter that writes in Parquet format in the form of either Avro, Protobuf or ParquetGroup. This implementation allows users to specify the CodecFactory to use through the configuration property writer.codec.type. By default, the snappy codec is used. See Developer Notes to make sure you are using the right Gobblin jar.

Usage

writer.builder.class=org.apache.gobblin.writer.ParquetDataWriterBuilder
writer.destination.type=HDFS
writer.output.format=PARQUET

Example Pipeline Configuration

• example-parquet.pull contains an example of generating test data and writing to Parquet files.

Configuration

Key	Description	Default Value	Required
writer.parquet.page.size	The page size threshold.	1048576	No
writer.parquet.dictionary.page.size	The block size threshold for the dictionary pages.	134217728	No
writer.parquet.dictionary	To turn dictionary encoding on. Parquet has a dictionary encoding for data with a small number of unique values ( < 10^5 ) that aids in significant compression and boosts processing speed.	true	No
writer.parquet.validate	To turn on validation using the schema. This validation is done by ParquetWriter not by Gobblin.	false	No
writer.parquet.version	Version of parquet writer to use. Available versions are v1 and v2.	v1	No
writer.parquet.format	In-memory format of the record being written to Parquet. Options are AVRO, PROTOBUF and GROUP	GROUP	No

Developer Notes

Gobblin provides integration with two different versions of Parquet through its modules. Use the appropriate jar based on the Parquet library you use in your code.

Jar	Dependency	Gobblin Release
gobblin-parquet	com.twitter:parquet-hadoop-bundle	>= 0.12.0
gobblin-parquet-apache	org.apache.parquet:parquet-hadoop	>= 0.15.0

If you want to look at the code, check out:

Module	File
gobblin-parquet	ParquetHdfsDataWriter
gobblin-parquet	ParquetDataWriterBuilder
gobblin-parquet-apache	ParquetHdfsDataWriter
gobblin-parquet-apache	ParquetDataWriterBuilder