fmnoise / penelope

Datomic transaction toolbox

Penelope

So every day I’d weave at the big loom.
But at night, once the torches were set up,
I’d unravel it.
The Odyssey, Book IX

Penelope is a Clojure utility library for preparing, transforming, and submitting transactions to Datomic.

Planned features:

• Flatten transaction map forms to datoms.
• Get a list of datoms for a pull expression.
• Complete transactions on a peer speculatively, check-and-set/abort/retry if an invariant is violated when the transactor attempts to apply it.
• Automatically split large transactions up intelligently (e.g. during a bulk import).
• Standard transaction metadata: tx saga, unexpanded tx, peer identifier, patch identifier
• Patches: pre+post condition invariants, splittable to mutiple txs, unique identifier, can be speculatively transacted.
• Transaction pipeliner.
• Undo a transaction.
• Reset values of a cardinality-many attribute
• Unique component entities.
• Sibling order attribute.
• History-collapsing: produce the minimum number of assertions (preserving tx history for those assertions) to recreate a non-history-database value. (I.e., elide retractions and assertions which were later retracted.)

License

Copyright © 2017 Francis Avila

Distributed under the Eclipse Public License either version 1.0 or (at your option) any later version.