...
- Aaron Birkland
- Esmé Cowles
- Peter Eichman
- Michael Nelson
- Ben Pennell
- Bethany Seeger
- Harihar Shankar
- Herbert Van de Sompel
- Joshua Westgard
- Jared Whiklo
- Andrew Woods
- Martin Klein
Agenda
- Indroductions
- Context: specifications and API alignment - terminology, resource versioning, authorization
- Design decisions
- Open questions
- Next steps
Notes
- API Alignment Sprints
- How to implement Memento in relation to LDP and WebAC
- Terminology: https://fcrepo.github.io/fcrepo-specification/#terminology
- LDPR
- LDP-RS
- LDP-NR
- LDPC
- LDPRv - any resource that can be versioned
- LDPCv - container of Mementos (is both LDPC and TimeMap)
- HvS: Is there a 'to'/'from' date associated with each LDPRm?
- yes, each version has a start date, and implicit end date
- HvS: Suggesting storing Memento data in the LDP-descriptor
- Are binaries and descriptions in versioning lock-step?
- BP: Using headers and not adding new triples
- Har: Are LDPR and LDPRv separate resources?
- No, they are the same. The LDPRv just notes that a resource can be versioned
Design
- Issue: referential integrity
- Issue: versioning of trees
Interactions
- Enabling versioning
- Each memento has its own URI
- Content-Location header has conflicting usage
- No on PUT and POST: can not use Content-Location as indirect ingest
- Yes, conflict may still exist on GET for both Memento and External purposes
- Need to consider if External content can be versioned
- HvS: Possibly External versioning is not permitted!
- Versioning binary descriptor would be valuable
- Check if a resource is versionable
- Check if the client can create versions
- Creating a new version of an LDPRv
- Allowing clients to provide Memento-Datetime header on POST
- Enables creation of old versions
- POST is idempotent
- TAR allows for updating system dates
- Allowing clients to provide Memento-Datetime header on POST
ACLs
- Resources can have ACLs associated with them
- Is there value in having different permissions on LDPRv and LDPCv?
- Restricted resource and restricted mementos, but TimeMap is open
- HvS: Mementos should likely have their own ACLs
- Proposal: three permissions: LDPRv, LDPCv, LDPRm(s)
Internal Representation of resources
- LDPCv will have RDF serialization, memento info will just be in headers
- iana:original and iana:timemap should be used
- W3C has just released a "time ontology"
- Consider using in TimeMap (LDPCv)
- Memento (LDPRm)
- Would be helpful to use start and end time of the memento
Finding the ACL on an LDPRm
- When looking for LDPRm that is before the initial datetime, you get first
- When looking for LDPRm that is after the last datetime, you get current
- This is in the Memento spec
- 4.5.3. Issues with Accept-Datetime
- Can remove LDPRms
Referential integrity
- Proposal: Ignore ref-integrity when removing linked resources
- Return 410 on deleted resources
Next Steps
- How should sprint-2 interact with Memento team?
- Harish is point of contact, this week
- email and phone
- HvS is available next week
- Harish is point of contact, this week
ACTION: have a check-in next week, Tue, 10/3 10amET