It is straight forward to check if a user has permission for a GET
request on a collection (e.g. /orders), but how does ABAC deal with items of collections? The user may have permission for some items of the collection, but not for others (e.g. the user can only see orders below 10.000 Euro).
Is a separate request to the PDP created for each object in the list or does the PDP accept a list of requests and return a list of decisions? Since the PIP doesn't know how the collection might be filtered, the decision about access permission can only be made after all objects are fetched.
The returned collection items may only return selected fields. The PIP therfore needs to make another request to fetch the missing attributes. During the time the attributes are fetched and the access is decided the data can have changed. The decision is then based on different states of the objects. How is this prevented?