[AVRO-2028] Specific Data, newBuilder(existingInstance) fails for BigDecimal

• Type: Bug
• Status: Open
• Priority: Major
• Resolution: Unresolved
• Affects Version/s: 1.8.2
• Component/s: java
• Assignee: Unassigned
• Reporter: Adrian McCague
• Created: 24/Apr/17 19:09
• Updated: 21/Oct/21 15:22

Description

Using 1.8.2-rc3

When attempting to use:
MyType.newBuilder(existingType)

With a field of type Union:

["null",{"type":"bytes","logicalType":"decimal","precision":20,"scale":8}]

I get the following exception:

org.apache.avro.UnresolvedUnionException: Not in union ["null",{"type":"bytes","logicalType":"decimal","precision":20,"scale":8}]: 12000.00000000

	at org.apache.avro.generic.GenericData.resolveUnion(GenericData.java:740)
	at org.apache.avro.generic.GenericData.deepCopyRaw(GenericData.java:1146)
	at org.apache.avro.generic.GenericData.deepCopy(GenericData.java:1062)
	at MyType$Builder.<init>

I suspected it may be related but also noticed in the generated Specific Data class the following:

private static final org.apache.avro.Conversion<?>[] conversions =
      new org.apache.avro.Conversion<?>[] {
      null,
      TIMESTAMP_CONVERSION,
      null,
      null, // Should be DECIMAL_CONVERSION
      null,
      null,
      null,
      null,
      null
  };

ie, the conversion was missing.
Adding this by hand however did not resolve the issue. I will add this as another issue.