Everything in an Islandora repository is an object. In Islandora, an object is a collection of properties describing something. Since Islandora 7 was built on top of Fedora an object in Islandora 7 is essentially a Fedora object. In Islandora 8, Drupal, and not Fedora, is the primary source of all aspects of an Islandora object. In Drupal terms, an Islandora 8 object is a node. As we learned in last week’s post on Drupal Nodes, nodes have properties that can be configured called fields. Fields for nodes are grouped together as content types.
The model for exactly what constitutes an object in Islandora 8 is flexible and can be adapted to users’ specific needs. The Islandora 8 default configuration considers an object as a node with the content type of Repository Item which contains descriptive metadata about the object. Attached to that node are one or more datastreams, each representing a file that is part of this object, such as Original File, Thumbnail, Preservation Master, etc. Metadata used to categorize objects are taxonomy terms, which also have their own fields. They can represent everything from simple labels to more complex concepts such as people, places, and subjects.
As we dig deeper into Islandora 8 keep in mind these details about an Islandora object:
- An Islandora object is a Drupal node.
- Drupal nodes have properties that can be configured called fields.
- Fields for nodes are grouped together as content types.
- Datastreams are files that can have their own fields and media types.
- Metadata used to categorize objects are taxonomy terms, which also have their own fields.
Fun Fact: The Islandora repositories hosted by PALS have a combined total of 472,621 objects.