[ https://issues.apache.org/jira/browse/PARQUET-2292?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=17715849#comment-17715849 ]
ASF GitHub Bot commented on PARQUET-2292: ----------------------------------------- RustedBones commented on code in PR #1078: URL: https://github.com/apache/parquet-mr/pull/1078#discussion_r1175343501 ########## parquet-avro/src/main/java/org/apache/parquet/avro/AvroRecordConverter.java: ########## @@ -169,6 +172,46 @@ public void add(Object value) { } } + /** + * Returns the specific data model for a given SpecificRecord schema by reflecting the underlying + * Avro class's `MODEL$` field, or Null if the class is not on the classpath or reflection fails. + */ + static SpecificData getModelForSchema(Schema schema) { + final Class<?> clazz; + + if (schema != null && (schema.getType() == Schema.Type.RECORD || schema.getType() == Schema.Type.UNION)) { + clazz = SpecificData.get().getClass(schema); + } else { + return null; + } + + final SpecificData model; + try { + final Field modelField = clazz.getDeclaredField("MODEL$"); + modelField.setAccessible(true); + + model = (SpecificData) modelField.get(null); + } catch (Exception e) { + return null; + } + + try { + final String avroVersion = Schema.Parser.class.getPackage().getImplementationVersion(); Review Comment: This won't work for avro pre 1.10 where the implementation version is not defined, and will return `null` Here is a [trick](https://github.com/sbt/sbt-avro/blob/ec5f8aa064d0314a97a876bfe1d2d1bdb26dcbb8/src/main/scala/com/github/sbt/avro/SbtAvro.scala#L28) to access the avro version for previous artifact > Improve default SpecificRecord model selection for Avro{Write,Read}Support > -------------------------------------------------------------------------- > > Key: PARQUET-2292 > URL: https://issues.apache.org/jira/browse/PARQUET-2292 > Project: Parquet > Issue Type: Improvement > Reporter: Claire McGinty > Assignee: Claire McGinty > Priority: Major > > AvroWriteSupport/AvroReadSupport can improve the precision of their default > `model` selection. Currently they default to new > SpecificDataSupplier().get()[0]. This means that SpecificRecord classes that > contain logical types will fail out-of-the-box unless a specific > DATA_SUPPLIER is configured that contains logical type conversions. > I think we can improve this and make logical types work by default by > defaulting to the value of the `MODEL$` field that every SpecificRecordBase > implementation contains, which already contains all the logical conversions > for that Avro type. It would require reflection, but that's what the Avro > library is already doing to fetch models for Specific types[1]. > > [0] > [https://github.com/apache/parquet-mr/blob/d38044f5395494e1543581a4b763f624305d3022/parquet-avro/src/main/java/org/apache/parquet/avro/AvroWriteSupport.java#L403-L407] > [1] > https://github.com/apache/avro/blob/release-1.11.1/lang/java/avro/src/main/java/org/apache/avro/specific/SpecificData.java#L76-L86 -- This message was sent by Atlassian Jira (v8.20.10#820010)