[AVRO-3761] UUID validation breaks nullable field

• Type: Bug
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 1.11.1
• Fix Version/s: 1.11.2
• Component/s: python
• Labels: pull-request-available

Environment

$ pip freeze | grep avro
avro==1.11.1
$ python --version
Python 3.8.16

Language

Python

• Assignee: Anton Agestam
• Reporter: Anton Agestam
• Created: 24/May/23 13:57
• Updated: 16/Jun/23 18:23
• Resolved: 16/Jun/23 07:28

Description

Using logical type UUID for a nullable field breaks when writing `None`.

import io
import uuid
from avro.io import DatumWriter, BinaryEncoder
import avro.schema

schema = avro.schema.parse("""
{
  "name": "Metadata",
  "type": "record",
  "fields": [
    {
      "name": "topic_id",
      "type": [
        {
          "logicalType": "uuid",
          "type": "string"
        },
        "null"
      ]
    }
  ]
}
""")


with io.BytesIO() as buffer:
    writer = DatumWriter(schema)
    encoder = BinaryEncoder(buffer)
    # This works.
    writer.write({"topic_id": uuid.uuid4().hex}, encoder)
    # This breaks.
    writer.write({"topic_id": None}, encoder)

Results in:

Traceback (most recent call last):
  File "reproduce-avro-uuid.py", line 32, in <module>
    writer.write({"topic_id": None}, encoder)
  File "/Users/anton/.pyenv/versions/karapace/lib/python3.8/site-packages/avro/io.py", line 1013, in write
    validate(self.writers_schema, datum, raise_on_error=True)
  File "/Users/anton/.pyenv/versions/karapace/lib/python3.8/site-packages/avro/io.py", line 142, in validate
    validated_schema = current_node.schema.validate(current_node.datum)
  File "/Users/anton/.pyenv/versions/karapace/lib/python3.8/site-packages/avro/schema.py", line 801, in validate
    if branch.validate(datum) is not None:
  File "/Users/anton/.pyenv/versions/karapace/lib/python3.8/site-packages/avro/schema.py", line 1048, in validate
    val = uuid.UUID(datum)
  File "/Users/anton/.pyenv/versions/3.8.16/lib/python3.8/uuid.py", line 165, in __init__
    raise TypeError('one of the hex, bytes, bytes_le, fields, '
TypeError: one of the hex, bytes, bytes_le, fields, or int arguments must be given

Issue Links

• is duplicated by: AVRO-3750 Python Optional UUIDs are not allowed
• links to: GitHub Pull Request #2249