[Proposed Work Item]: Data range vocabulary

[renyuneyun]

Given that #56 and #63 (and #57) exists, I would like to propose this work item, also as a way to facilitate them: to create a vocabulary appropriate for Solid to describe the "range" of data targets. This "range" can be used by:

1. Apps (including services) to describe the range of data read by them;
2. Apps (including services) to describe the location/range of data written by them;
3. Policies to describe the range of applicable data.

Therefore, we will have a common vocabulary for interoperation and exchange between apps and policies.

The vocabulary should be appropriate for Solid, at least in the following aspects:

1. Can describe data residing in one's own Pod;
2. Can handle multiple Pods (owned or not by the same person / ID);
3. Be explicit about the semantics of overlapping ranges (composable? error?);
4. Consider location-specific range, and/or Index-based range, and/or other cases;
5. Be cautious about the evaluation overhead of multiple complex ranges;
6. (Hopefully) be visualizable.

Deliverables:

• Spec draft
• Vocabs
• Sample implementation
• Conformance test utilities

[uvdsl]

Is this also related to #57 in the sense of "apps describe what data they request to access" ?
This could include the mode of access (CRUD operations) and the purpose of processing or storing data (usage control).
Could this issue be a sub-issue of #57?

[renyuneyun]

@uvdsl Definitely! Now added it to the list as well.

But I feel this is separate from policy, because this is useful for non-policy items such as #63. But I'm happy for either way as long as it moves forward, and will join the conversation wherever it happens :)