Comment 4 for bug 1989393

It may be that there is an issue with default values for config attributes. Taking a few examples:

applications:
  barbican:
    options:
      action-managed-upgrade:
        bundle: null
        model: false

That says that the bundle does not define the 'action-managed-upgrade' value, but the model does have a value for it, and that value is 'false'.

Similarly for:
      max-allowed-request-size:
        bundle: null
        model: 25000

max-allowed-request-size is 25,000 in the model, but there is no value in the bundle.

My guess is that the model values are from defaults in the charm. But it does seem like 'diff-bundle' should be taking that sort of thing into account. Either export-bundle should be including the current values, or diff-bundle should be understanding default values.