One of the main goals of the CEDAR project is to build an infrastructure for the creation and storage of machine-readable metadata templates. Toward that end, we have defined a JSON-based metadata model in which templates, elements, and fields are defined in JSON Schema, and the JSON-LD metadata instances are specified by the corresponding template. The specification allows CEDAR metadata to be used by CEDAR, and exchanged with other metadata systems.
This approach yields several advantages:
- straightforward programmatic access to metadata content in JSON
- convertibility of semantically meaningful metadata to RDF
- straightforward composition of templates from modular components
- immediate validation of JSON-LD instances using their parent schema
- a well-defined interoperable specification that can express multiple data standards
The simplest description of CEDAR's model can be found at our wiki page CEDAR Template, Element, and Field Instances.
We have written a technical report (in the attachment below) that describes in some detail the format of the templates, elements, and instances that make up the CEDAR metadata framework.
We also have written a paper describing the model, which provides a more formal written description but has less technical detail.