Four extractions, each chosen because the two halves have different callers,
different failure modes or different testing needs. Not a line-count exercise.
internal/home out of internal/media
- media serves item RESOURCES (detail, file, cover, progress); home computes
AGGREGATES (the five shelves). The 2328-line package was doing both.
- media keeps POST /items/{id}/view because it is item-scoped and must stay in
the package that authorizes the item; it imports home.RecordView for that one
thing. home does not import media.
- Verified live: all five shelves non-empty, and two consecutive /home calls
return different explore ids, which is the non-determinism the Explore rewrite
exists for.
internal/scanner out of internal/library
- The scanner walks the filesystem and reconciles; library CRUD is an admin HTTP
surface. Different callers (a job vs a request), different failure modes.
- The registry deliberately STAYED in internal/library: three of its four callers
are not the scanner (modules register types, handlers serve the list, metadata
reads the group mode, subsonic calls CleanTitle). It is a property of the kind,
not of the scan. The one genuinely scanner-owned helper became
library.ExtensionsFor.
- Two tests moved with the code rather than being rewritten; they now exercise
the boundary by calling library.ListMissing across it.
- Verified live: first scan updates, rescan reports unchanged=N, so change
detection still short-circuits.
internal/providers out of internal/metadata
- Providers talk to third-party APIs; the enrich job owns the matching policy and
the database writes. The split's whole point is that a provider is testable
WITHOUT a database, so a DB-free test was added and OpenLibrary gained a
BaseURL override to make it possible.
- providers imports zero internal packages — a true leaf.
- The matching policy (searchTitle, artistHint, pickBest) is untouched. It exists
because real false matches were found.
dto packages out of internal/jellyfin and internal/subsonic
- The wire types and their mapping are now separate from the handler logic, so
the contract with clients we do not control is reviewable on its own.
- Both dto packages are PURE: zero references to sql.DB or net/http, verified by
grep. That is what makes them reviewable.
- No field name, tag or error code changed.
internal/arch did its job: it failed the build twice during this phase, once for
each new package that was not yet placed in a layer. That is the rule working,
not an obstacle.
Verified: gofmt clean, build exit 0, vet exit 0, 23 packages pass, svelte-check
0/0, and end to end against a running server — home shelves, a queued scan
reporting unchanged, Jellyfin /Items, and Subsonic ping.
Process note: one agent (dto) stopped mid-task and left the tree red — the dto
packages unlayered and its test still referencing constants that had moved. The
arch test caught it immediately. I finished it by hand: exported constant
references in the test, and both dto packages placed at layer 3.
Still open from Phase 1: internal/jellyfin has no test files, catalog is
item-centric while Subsonic is file-first, and subsonic loadAlbum now scopes to
the item's own library.
- jobs: a table-backed queue in the same SQLite file. No Redis, no second
process, included in the same backup. claim() is a single UPDATE...RETURNING
so a job cannot run twice even with several workers. Failures back off
exponentially; a missing handler fails permanently rather than retrying a
bug.
- metadata: Provider interface plus Open Library and Google Books (both
keyless). The enricher tries providers in registration order, falls back on
empty, and continues past a provider error.
- migration 0004: metadata_fetch records the attempt, not just the match, so a
rescan does not re-hammer a rate-limited API for an item that will never
match. Errors are always retried; ok/notfound are cached for 30 days.
- enrichment writes provider_ids, updates title/year, links authors through
people/item_people, and downloads the cover as an asset. The cover download
runs outside the transaction: a slow image host must not hold a write lock.
- endpoints: queue enrichment per library, and inspect an item's matches.
- web: Enrich button per library.
Verified live against Open Library: "The Hobbit" matched /works/OL27482W,
title and year 1937 written, a 301x500 JPEG cover downloaded and served.