Link3 Rest Api Outbox filters

When using the REST Api to get outbox documents it would be very useful to be able to filter for certain conditions.

For instance when getting some document type from the outbox it would be helpful to be able to specify format/variant/version.

We have a customer which uses two different flows for the same document type but with different formats. One format is in Xml and the other is in JSON.

If it was possible to GET Outbox document types for a specific format, this task would be trivial to solve. As it is now, it is not possible to solve this specific problem.

If no filter is provided for format/variant/version, then all documents are returned from the outbox. If a filter is provided then only documents matching that filter should be returned.