[AVRO-1815] Incompatible schema change not detected when wrapped in a UNION

• Type: Bug
• Status: Resolved
• Priority: Major
• Resolution: Duplicate
• Affects Version/s: 1.7.7
• Component/s: java
• Assignee: Unassigned
• Reporter: Martin Boyle
• Created: 22/Mar/16 11:01
• Updated: 16/Nov/17 13:54
• Resolved: 16/Nov/17 13:54

Description

An incompatible schema change is not detected when it is in a UNION and the change is to the value type of a map e.g.

field

{ "name": "segmentEkv", "type": ["null", {"type": "map", "values": {"type": "map", "values": "string"}}], "default": null},

changes to

{ "name": "segmentEkv", "type": ["null", {"type": "map", "values": {"type": "array", "items": "int"}}], "default": null},

The SchemaValidatorBuilder() will pass this as being compatible. Whereas SchemaCompatibility.check_reader_writer_compatibility will return an incompatible result. The problem for me is that the Confluent Schema Registry uses SchemaValidatorBuilder.

Problem appears to be that while the ResolvingGrammerGenerator correctly marks the field as being an incompatible change, the check for errors on the Symbol object does not descend into the UnionAdjustActionField

Issue Links

• duplicates: AVRO-1883 Schema validator cannot find broken backwards compatibility in Union type elements