Basic resource typing through HTTP Link header

[csarven]

In order to promote ad hoc discovery of information, servers practice advertising self-describing resources. One way for servers to do this is by advertising the resource type (rel=type) in HTTP Link header. Explicit types can also help to categorise resource lifecycles (for server's management) and data partitioning eg. it is somewhat integral to LDP given its interaction models. When a client encounters Web resources without context, they can at least have a basic understanding what a resource may contain provided that they meet the authorization requirements.

Some cases are listed below and certainly there are others. Should the Solid spec have a requirement (at any level / case by case) for significant types that can be encountered in the ecosystem?

• Container type (eg. ldp:Container, ldp:BasicContainer): Add heuristic to determine resource type #160 (comment) (see also Remove server requirement to advertise container type in HTTP header #190 )

• LDP compatibility (eg. ldp:Resource): https://www.w3.org/TR/ldp/

• Solid resource (eg. solid:Resource): Enable full use of relative URLs in Solid #194 (comment) explains (with some diff to ldp:Resource).

• Storage (eg. pim:Storage): Should it be possible to find controller of storage via resources? #153 (comment) to help client determine root container - on way to discovering its creator/controller.

• WAC/Access-control list (eg. solid:AccessControlList): Handling requests without an interaction model #105 (comment) to help client determine that a resource contains authorization policies. Related: How does the server determine whether a resource is an ACL resource? #31

• Memento types (eg. mem:Memento, mem:OriginalResource): Creation of Memento resources #61

• Fixed resource (eg. http://www.w3.org/2006/gen/ont#FixedResource)

• Shapes tree (eg. tree:shapeTreeResource): https://shapetrees.github.io/specification/primer

• Provenance (eg. solid:Provenance ): after via rel="http://www.w3.org/ns/prov#has_provenance": Clarify the notion and mechanisms for server-managed information #177 (comment) where it can contain provenance record (mix of activity, entity, agent..)

• ODRL resource: (eg. http://www.w3.org/ns/odrl/2/Resource): potentially described in the formal-semantics document with the ODRL link relation type (eg. odrl:has_policy): Discovery of an ODRL resource w3c/odrl#12

• Other partitioning: Handling requests without an interaction model #105 (comment)

• ?