[AVRO-2140] Validation of Union Schemas

• Type: Improvement
• Status: Open
• Priority: Minor
• Resolution: Unresolved
• Affects Version/s: 1.8.2
• Component/s: java
• Assignee: Unassigned
• Reporter: Marcos Lopez Gonzalez
• Created: 02/Feb/18 15:07
• Updated: 20/Aug/20 05:51

Description

When validating a union Schema in the method

Schema.isValidDefault(Schema schema, JsonNode defaultValue)

for the case of UNION it only validates the first type of the union: 

case UNION: // union default: first branch
return isValidDefault(schema.getTypes().get(0), defaultValue);

This leads to some warnings that can create confusion.

For example, if you have a field like this:

{
  "name" : "synonym",
  "type" : [ "null", "boolean" ],
  "default" : false
}

and you assign it false as default you get this warning because it only validates that false is not null:

[WARNING] Avro: Invalid default for field synonym: false not a ["null","boolean"]

I think in this cases the validation should check all the types of the union to avoid these warnings.

I would be happy to create a PR to improve this if you think we should go for it.