Templates: Core Structure

A template is a complete metadata specification: an ordered set of elements and fields that describe one kind of thing. In YAML it is written with type: template, its elements and fields listed under children:

type: template
name: Study
children:
- key: study-name
  type: text-field
  name: Study Name
- key: address
  type: element
  name: Address

Each entry in children is a field or element, told apart by its own type. Its key is the master identifier for the child. It must be unique among the parent's children, and it is what indexing, integrity checking, and instances all refer to. Its name is purely for presentation. A value in an instance is bound to a child by its key, never by its name.

Template Keys

Beyond the core keys every artifact carries, a template can carry a header and a footer, content shown above and below the form.

Key	Value	Presence	Meaning
header	string	optional	Content shown above the form.
footer	string	optional	Content shown below the form.

Instance Type

A template may declare an instanceType, the RDF type asserted on instances created from it. This is what lets an instance be read as Linked Data; see Mapping to RDF.

Key	Value	Presence	Meaning
instanceType	IRI	optional	The type asserted on instances created from this template.