Are relations worth keeping?

[8e8b2c]

Currently OracleDocument relation links are only utilised by the holoom block explorer. Recipes do not support fetching documents by relation, because there is no way to prevent a an executor from censoring an item from the collection.

I can think of a somewhat convoluted approach to preventing censorship: A recipe names some future checkpoint document on an authority chain, and then once it exists, its action hash used as an upper bound for validating and aggregating relation information on the chain. However, it's worth questioning if this approach has significant advantages over the simpler approach of waiting for some future document list instead.

Pros

• It removes an opportunity for an authority to retrospectively censor an item from the list they publish

Cons

• It increases the complexity of aggregating documents sourced from multiple authorities, as future checkpoints would have to named per authority.

[8e8b2c]

The "Happ performs pattern search" approach of #18 could potentially pave the way to another feature: the retrospective indexing of documents by 3rd parties. Such a feature would make verifiable collections more useful.