[NIFI-7925] ValidateRecord reports false positive for avro arrays with null elements

• Type: Bug
• Status: Resolved
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 1.12.1
• Fix Version/s: 1.13.0
• Assignee: Denes Arvay
• Reporter: Christophe Monnet
• Created: 15/Oct/20 08:11
• Updated: 28/Feb/22 20:42
• Resolved: 28/Feb/22 20:42

Description

with this avro schema:

{
    "type": "record",
    "name": "simple",
    "fields": [{
        "name": "stuff",
        "type": {
            "type": "record",
            "name": "stuff",
            "namespace": "simple",
            "fields": [{
                    "name": "languages",
                    "type": {
                        "type": "array",
                        "items": ["null", "string"]
                    },
                    "doc": ""
                }
            ]
        },
        "doc": ""
    }
    ]
}

and this payload:

{"stuff":{"languages":[null]}}

ValidateRecord fails with
Records in this FlowFile were invalid for the following reasons: ; The following 1 fields had values whose type did not match the schema: [/stuff/languages]

But when using avrotool I can convert the payload:

$ avrotool fromjson --schema-file schema.json payload.json > payload.avro
$ avrotool tojson payload.avro
{"stuff":{"languages":[null]}}

Moreover with this payload

{"stuff":{"languages":[]}}

ValidateRecord routes to the valid queue.

Therefore I suspect that ValidateRecord has a bug when it comes to arrays with nullable items.

Issue Links

• links to: GitHub Pull Request #4611