2018 Spring API Alignment Sprint 1 Planning

Change the PreferInboundReferences URI in Prefer header

from http://fedora.info/definitions/v4/repository#InboundReferences to the one defined in the spec (ie http://fedora.info/definitions/fcrepo#PreferInboundReferences)

• Though the message coming back in the case of an attempt to move from RDFSource to NonRDFSource says "Resource Already Exists" instead of returning a constrained by header
• Same message is returned trying to move from ldp:Container to an ldp:DirectContainer or ldp:BasicContainer or ldp:Container

MUST change resource's type if request's type Link is a subtype of resource's current type

MUST change resource's interaction model if request's type Link has an LDP interaction model

Using PATCH it is currently possible to add an rdf:type of ldp:NonRDFSource to an existing ldp:RDFSource. This should fail with a 409.

The Accept-Datetime header is used to request a past state, exactly as per [RFC7089] section 2.1.1. A successful response must be a 302 (Found) redirect to the appropriate LDPRm

If no LDPRm is appropriate to the Accept-Datetime value, an implementation should return a 406 (Unacceptable).

The response to a GET request on an LDPRv must include the following headers

• A <http://mementoweb.org/ns#TimeGate>; rel="type" link in the Link header
• A  <http://mementoweb.org/ns#OriginalResource>; rel="type" link in the Link header

LDPm GET

• An implementation must support GET, as is the case for any LDPR.
• The headers for GET requests and responses on this resource must conform to [RFC7089] section 2.1. Particularly it should be noted that the relevant TimeGate for an LDPRm is the original versioned LDPRv.
• In addition, any response to a GET request must include a <http://mementoweb.org/ns#Memento>; rel="type" link in the Link header.

LPPm OPTIONS

•  An implementation must support OPTIONS.
•  A response to an OPTIONS request must include Allow: GET, HEAD, OPTIONS as per [LDP].
•  An implementation may include Allow: DELETE if clients can remove a version from the version history, as noted in 3.8 HTTP DELETE.

LDPm: DELETE

The server is responsible for all behaviors implied by the LDP-containment of the LDPRm.

LDPCv : An implementation must support GET, as is the case for any LDPR. Any response to a GET request must include a <http://mementoweb.org/ns#TimeMap>; rel="type" link in the Link header. Currently the <http://fedora.info/definitions/v4/repository#TimeMap> is being used.

LDPCv: POST

• A POST that does not contain a Memento-Datetime header should be understood to create a new LDPRm contained by the LDPCv, reflecting the state of the LDPRv at the time of the POST. Any request body must be ignored.
• A Memento-Datetime header should be understood to create a new LDPRm contained by the LDPCv, with the state given in the request body and the datetime given in the Memento-Datetime request header.

LDPCv: DELETE:

Delete of an LDPCv must remove the LDPCv and removing the versioning interaction model from the original LDPRv.

Vary :

When an LDPCv supports POST, and allows clients to specify a datetime for created URI-Ms, Vary-Post/Vary-Put: Memento-Datetime.

Replacing Contents from Mementos

Non-normative note: Using the ingest-by-reference mechanism, one can replace the contents of an LDPRvwith that of an LDPRm by providing it's URL as the URL parameter in a Content-Type: message/external-body header. For example, given an LDPRm with URL http://example.org/some/memento, the full header would be 
Content-Type: message/external-body; access-type=URL; expiration=1;
    URL="http://example.org/some/memento"

Restrict Cross Domain ACLs

•  it MUST respond with a 4xx range status code
•  and MUST advertise the restriction with a rel="http://www.w3.org/ns/ldp#constrainedBy" link in the Link response header.

When an ACL includes an acl:accessToClass statement, it gives access to all resources with the specified type, whether that type is client-managed or server-managed.