1. Collections
Collections are a means to organize objects in a hierarchical structure - like folders in a file system.
The purpose of collections:
- define write rules (who may deposit a new object)
- search constraint
- structure for browsing
Collection Object:
- Obj ID (FOXML)
- title, write permissions
- aribtrary number of nesting levels are allowed.
Notice that a collection should not be used to store different representations of the same object. In such case, the representations should be stored in a single object in the datastreams DS1...DSn (see 3.5)
1.1. Basic Collection Object
The Basic Collection Object serves as a simple container for other objects or sub-collections. It has a name and defines which aai-identified persons have the right to create new objects or sub-collections in the collection.
1.1.1. Basic Collection Datastreams
| ID | Label | Description |
| Internal FOXML | Object ID (pid) | |
| DC | Dublin Core | Generated and used internally by Fedora. Don’t touch this! |
| CHOR_DC | SWITCHcollection application profile of Dublin Core |
|
| RELS-EXT | RELS-EXT | Relations to collection and content model |
1.1.2. Datastream CHOR_DC: Mandatory Elements
| Element | Description | Examples |
| title | The name or title of the collection | “DNA from the Beginning” |
| aaiid | AAI ID of the creator of the collection. | “3562781242@zhaw.ch” |
| rights | Who may add new items to the collection | Private, group, institution, public. Preliminary simple syntax: “private” “group=<aai-group-id>” “institution=<aai-home-organization>” “public” |
1.1.3. Datastream RELS-EXT
This datastream specifies relations of the collection object to other collections and to the content model. Both RDF elements are mandatory.
| Label | Description |
| rel:isMemberOfCollection | Reference to the collection object that contains the resource |
| rel:conformsTo | Reference to content model object basic collection |
| oai:setSpec | Colon separated list indicating the path from the root of the set (=collection) hierarchy to the respective node. Examples: “ethz:dagrl:phytopathology”; “subject:science:geology:earthquake” |
| oai:setName | Human-readable string naming the set |
2.2. Typed Collection Object
The Typed Collection Object is an extension to the Basic Collection Object described above. Its purpose is to specify a collection of 1) a defined type and 2) to add more metadata to a collection object than just a title.
Typed Collection Objects are useful if groups of objects logically belong together and have to be interpreted or treated in a special way. A typical example are collections of video clips that all belong to the same lecture (channel), or lessons or different material that belong to a course.
2.2.1. Typed Collection Datastreams
The Typed Collection Datastreams are exactly the same as for the Basic Collection.
2.2.2. Datastream CHOR_DC: Elements
The DC datastream of a typed collection is mostly the same as for the Basic Object (see 3.3, 3.3.2). These are the differences to the DC datastream of the Basic Object model:
- The elements title, aaiid, rights have the same meaning as for the Basic Collection Object
- The elements license are not mandatory
2.2.3. Datastream RELS-EXT
This datastream specifies relations of the collection object to other collections and to the content model. Both RDF elements are mandatory.
| Label | Description |
| rel:isMemberOfCollection | Reference to the collection object that contains the resource |
| rel:conformsTo |
Reference to the content model object for the specified collection type. The following collection types are specified:
|
| oai:setSpec | Colon separated list indicating the path from the root of the set (=collection) hierarchy to the respective node. Examples: “ethz:dagrl:phytopathology”; “subject:science:geology:earthquake” |
| oai:setName | Human-readable string naming the set |