Embargos and Leases

Definitions: Lease: Access is restricted after an expiration date. Embargo: Access is restricted until a release date. Visibility: A group of users who may view or discover an object at a particular point in time.

Overview: In Hydra leases and embargos that can go from an arbitrary visibility before the expiration/release to another visibility state.

Technical Problem: It's hard to write a Solr query for object discovery that is aware of both lease and embargo with multiple possible before and after visibility states.

Solution: In HydraRightsMetadata we encode only the intention of the lease or embargo.

All access to an object is based on current group/user visibility. We have methods to find digital objects that have expired leases or embargos past their release date. We have another method that applies the intention of the lease and embargo to the groups/users. When this happens the lease and embargo would be removed from HydraRightsMetadata and a message such as: "This object had an embargo that expired on 2014-05-31. At that time it was made 'public'" will be written to the human readable section of the embargo/lease. An implementer can use a scheduled (cron) job to apply these changes, or a separate controller can be used for manual application of the lease/embargo changes.