Currently crunch is supporting avro to parquet conversion using AvroParquetFileTarget, AvroParquetFileSource classes. When I used these classes to convert avro to parquet files, I got the following exception in some cases: "org.apache.crunch.CrunchRuntimeException: parquet.io.ParquetEncodingException: empty fields are illegal, the field should be ommited completely instead"
After further debugging I found out that this issue is related to AvroWriteSupport class in parquet, which was fixed as part of milestone 1.2.3 https://github.com/Parquet/parquet-mr/issues/162. Latest parquet version is 1.3.2.
But crunch is still using parquet 1.2.0 https://github.com/apache/crunch/blob/master/pom.xml#L77
As part of this improvement, parquet dependency version in crunch will be updated if not to latest then at least to 1.2.3