Schema/constraint configuration in data

[gsvarovsky]

what

Use (a sub-/super-set of) a schema language like SHACL or ShEx to define constraints, in the domain data.

why

Key to decentralised extensibility. See Realtime Information Sharing with RDF (paper).

• Allows apps to dynamically adapt the presentation of information as their rules evolve.
• Gives users more freedom to change which app they use, while keeping their data intact.

Authorisation implications are being investigated in m-ld/m-ld-security-spec#2

Potential issue: schema constraint checking could be naively O(number of schema classes x number of subjects in the update), because a change may not include type information. Need to establish @type early.

[gsvarovsky]

Candidate schema model: Atomic Schema

[gsvarovsky]

Candidate schema model: using OWL with a closed-world mode, as decided on for TerminusDB

• Intro to classes/properties/restrictions

[gsvarovsky]

Candidate schema model: SHACL (link to example).

• JS package – validates a dataset, has nothing to say about transactions
• RDF4J support – validation on transaction commit
• Jena support

[gsvarovsky]

Candidate schema model: LinkML

[gsvarovsky]

Candidate schema model: JSON Type Definition

{
    "properties": {
        "name": { "type": "string" },
        "isAdmin": { "type": "boolean" }
    },
    "optionalProperties": {
        "middleName": { "type": "string" }
    }
}