`undefined` is missing from exported JSON

[nkooman-bzs]

Brief bug description

When data is exported any fields that are set to undefined will not be present in the resulting JSON output.

Repro steps

1. Export a content item that includes an empty field
   • Ex: Non-required number element or text element
2. Run the export command
3. See that the value field does not exist

Expected behavior

The value field has a value.

Test environment

N/A

Additional context

undefined is not a valid value per the JSON specification.

The import will gracefully handle a missing value field. Accessing data.value when value is missing still results in undefined.
However, this can cause issues when a user wishes to directly interact with the exported JSON, expecting the value field to exist. Also, values of 0 and an empty string will not be imported correct, resulting in incorrect migrations.

I believe the fix to this issue would be to use null instead of undefined to represent an empty field.

Screenshots

[Enngage]

Hi @nkooman-bzs,

This was an intentional choice to use undefined as it makes the output json less verbose. While the null would be preserved in json I'm not quite sure if we want to make this breaking change.

I'm open to revisit this topic in future, but for now I don't think we'll pursue this.