ModuleDraft 0.1, for comment

Collector module (draft 0.1)

Status: draft for comment. Namespace: org.openmusiccollection.collector. Needs: Core 1.0.

Record collectors keep more than what they have now: what they paid and where, which records they sold, lent to a friend or gave away. The core records a physical copy's format, condition and location; this module adds a copy's history, so that it survives moving between apps and doesn't vanish when the record leaves the shelf.

#Sketch

On a copy, in its ext:

"ext": {
  "org.openmusiccollection.collector": {
    "acquired": { "at": "2019-05-04", "from": "Rough Trade East", "paid": { "amount": "24.99", "currency": "GBP" } },
    "gone": { "status": "lent", "at": "2026-09-12", "to": "Sam" }
  }
}

• acquired: when (partial date), from whom or where, and what was paid. Amounts are decimal strings with an ISO 4217 currency, so no money is lost to floating point.
• gone: a copy the person no longer has. status is sold, lent, given or lost (an open list), with at, to (a name, for people), and for sold a price.
• Core wins. A copy that is gone is not owned any more: its core ownership is none, and the module says why. A lent copy keeps its ownership (it is still the person's) and says where it is. When the record comes back, gone is removed.
• A copy that is gone stays in the collection, so the history isn't lost; apps that don't know the module show it as a record the person keeps without owning, which is true.

#Open questions

1. Should the value of a collection (a marketplace's current price) belong here, or in Catalog and Commerce?
2. Should several past owners (provenance for rare records) be listed?
3. Lending reminders: an app feature, or a date in gone (due)?

#Prior art

Discogs' collection fields (media and sleeve condition, notes, price paid in custom fields), Goldmine grading, CLZ Music.