[AVRO-2897] Unable to create nullable fields in Avro JavaScript implementation

• Type: Bug
• Status: Open
• Priority: Major
• Resolution: Unresolved
• Affects Version/s: 1.10.0
• Component/s: javascript
• Assignee: Unassigned
• Reporter: Mattias Andersson
• Created: 17/Jul/20 20:41
• Updated: 18/Jul/20 06:55

Description

 

I apologize in advance if this is a misunderstanding of funcitonality on my part and I have only tested it on the latest published npm package (https://www.npmjs.com/package/avro-js) but if not this should be a rather serious bug.

According to multiple sources (https://avro.apache.org/docs/1.8.1/spec.htm), nullable values should be specified as a unon with the type null, e.g. for string "['null', 'string']"

However, given the following code (that from what I understand should be valid)

var type = avro.parse({
  name: 'Pet',
  type: 'record',
  fields: [
    { name: 'name', type: ['null', 'string'] }
  ]
});
var pet = { name: "Fido" };
var buf = type.toBuffer(pet);
var obj = type.fromBuffer(buf);
console.log(obj);

I get the followin error on "type.toBuffer(pet)"

Error: invalid ["null","string"]: "Fido"

 

Curiously, if I instead set pet name as "null" instead of "Fido" everything runs fine and returns a correct output given the input. Though this is not very useful as the field still can not be changed to anything else beside null.

...
var pet = { name: null };
...
console.log(obj);

Pet { name: null }

 

Expected behavior is that both string and null should be valid parameters without throwing an exception.