null values not supported in JSON API

[eddavisson]

The following request:

{
 "mode": "NON_TRANSACTIONAL",
 "mutation": {
  "insertAutoId": [
   {
    "key": {
     "path": [
      {
       "kind": "test"
      }
     ]
    },
    "properties": {
     "propertyName": {
     }
    }
   }
  ]
 }
}

results in this response:

400 Bad Request

{
 "error": {
  "errors": [
   {
    "domain": "global",
    "reason": "INVALID_ARGUMENT",
    "message": "Property \"propertyName\" has no value.",
   }
  ],
  "code": 400,
  "message": "Property \"propertyName\" has no value."
 }
}

Null values work correctly in the proto API but not JSON.

http://stackoverflow.com/questions/24141010/json-structure-to-insert-a-null-value-for-a-property-into-google-cloud-datastore/24174662

[eddavisson]

b/15585044

[afri]

FWIW, in a listValue the API tolerates null values, but (incorrectly) ignores them.
The request

{ mutation: { upsert: [
   {
      key: key,
      properties: {
        test: { listValue: [ {}, {stringValue: 'foo'}, {}, {stringValue: 'bar'} ] }
      }
   }]}
}

succeeds, but then yields the following on a subsequent lookup:

{
  ...
  properties: { 
    test: {
      listValue: [
        { stringValue: 'foo' },
        { stringValue: 'bar' }
      ]
    }
  }
}

The null values have vanished.

[eddavisson]

The v1beta3 API adds an explicit null value type.