[AVRO-1810] GenericDatumWriter broken with Enum

• Type: Bug
• Status: Resolved
• Priority: Blocker
• Resolution: Fixed
• Affects Version/s: 1.8.0
• Fix Version/s: 1.9.0
• Component/s: java
• Assignee: Fokko Driesprong
• Reporter: Ryon Day
• Created: 10/Mar/16 19:05
• Updated: 13/Mar/20 16:50
• Resolved: 04/Mar/19 22:45

Description

Description

Using the GenericDatumWriter with either Generic OR SpecificRecord will break if an Enum is present.

Steps To Reproduce

I have been tracking Avro decoding oddities for a while.
The tests for this issue can be found here

Notes

Due to the debacle that is the Avro "UTF8" object, we have been avoiding it by using the following scheme:

• Write incoming records to a byte array using the GenericDatumWriter
• Read back the byte array to our compiled Java domain objects using a SpecificDatumWriter

This worked great with Avro 1.7.7, and this is a binary-incompatable breaking change with 1.8.0.

This would appear to be caused by an addition in the GenericDatumWriter:163-164:

  if (!data.isEnum(datum))
      throw new AvroTypeException("Not an enum: "+datum);

Issue Links

• relates to: AVRO-1870 Avro compiler generate JAVA enum interfaces but writeEnum expects GenericEnumSymbol
• links to: GitHub Pull Request #454
• links to: GitHub Pull Request #462