Files
Jonathan 034ae40084 feat(worker): share the MusicBrainz cache from scans/discovery
The worker's MB browser (discography + artist search, used by monitor sweeps,
library scans, and Last.fm discovery) re-fetched every time. Route it through
the same ApiCache table + logical keys the web app uses, so a discography one
process fetched warms the other, and repeat lookups stop hitting MB.

- apicache.py cached_api(): read-through, serve-stale-on-outage, never caches
  null, best-effort (a cache-DB error degrades to a live fetch, never breaks
  scan/sweep/discovery). Its own DEDICATED autocommit connection so it can't
  commit the worker's in-flight transaction, and autocommit avoids freezing
  Postgres now() (which would break TTL math).
- CachingMbBrowser decorates MusicBrainzBrowser, serializing to the SAME
  camelCase JSON shape the web writes (round-trip tested). registry.build_browser
  wraps it when a DSN is present; the Last.fm source's browser rides it too.
- Hourly prune drops ApiCache rows > 90d so the table stays bounded.
- worker 213 tests / 7-skip.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
2026-07-14 11:17:51 +02:00

111 lines
4.3 KiB
Python

from lyra_worker.apicache import DAY, MONTH, cached_api, norm_key, open_cache_conn
from lyra_worker.browser import ArtistHit, ReleaseGroupInfo
# Serialize to the SAME camelCase JSON shape the web app stores (web/src/lib/musicbrainz.ts),
# so a discography one process fetched warms the cache for the other.
def _artist_hit_to_json(a: ArtistHit) -> dict:
return {"mbid": a.mbid, "name": a.name, "disambiguation": a.disambiguation}
def _artist_hit_from_json(d: dict) -> ArtistHit:
return ArtistHit(mbid=d["mbid"], name=d.get("name", ""), disambiguation=d.get("disambiguation", ""))
def _rg_to_json(r: ReleaseGroupInfo) -> dict:
return {
"rgMbid": r.rg_mbid,
"title": r.title,
"primaryType": r.primary_type or None,
"secondaryTypes": list(r.secondary_types),
"firstReleaseDate": r.first_release_date or None,
}
def _rg_from_json(d: dict) -> ReleaseGroupInfo:
return ReleaseGroupInfo(
rg_mbid=d["rgMbid"],
title=d.get("title", "") or "",
primary_type=d.get("primaryType") or "",
secondary_types=tuple(d.get("secondaryTypes") or ()),
first_release_date=d.get("firstReleaseDate") or "",
)
class CachingMbBrowser:
"""Wraps an MbBrowser with the shared ApiCache read-through, keyed on the same logical
strings the web side uses (`artist-search:{q}`, `artist-rgs:{mbid}`). Uses a dedicated,
lazily (re)opened cache connection; if it can't connect, it just calls through uncached."""
def __init__(self, inner, dsn: str):
self._inner = inner
self._dsn = dsn
self._conn = None
def _cache_conn(self):
if self._conn is not None and not self._conn.closed:
return self._conn
self._conn = open_cache_conn(self._dsn)
return self._conn
def search_artist(self, name: str) -> list[ArtistHit]:
conn = self._cache_conn()
if conn is None:
return self._inner.search_artist(name)
key = f"artist-search:{norm_key(name)}"
rows = cached_api(conn, key, DAY,
lambda: [_artist_hit_to_json(a) for a in self._inner.search_artist(name)])
return [_artist_hit_from_json(d) for d in rows]
def browse_release_groups(self, artist_mbid: str) -> list[ReleaseGroupInfo]:
conn = self._cache_conn()
if conn is None:
return self._inner.browse_release_groups(artist_mbid)
key = f"artist-rgs:{artist_mbid}"
rows = cached_api(conn, key, MONTH,
lambda: [_rg_to_json(r) for r in self._inner.browse_release_groups(artist_mbid)])
return [_rg_from_json(d) for d in rows]
class MusicBrainzBrowser:
"""Real MbBrowser via musicbrainzngs (imported lazily; not unit-tested offline)."""
def __init__(self, app_name: str = "Lyra", version: str = "0.1", contact: str = "lyra@localhost"):
self._app, self._version, self._contact = app_name, version, contact
def _ua(self):
import musicbrainzngs
musicbrainzngs.set_useragent(self._app, self._version, self._contact)
return musicbrainzngs
def search_artist(self, name: str) -> list[ArtistHit]:
mb = self._ua()
res = mb.search_artists(query=name, limit=8)
return [
ArtistHit(mbid=a["id"], name=a.get("name", ""), disambiguation=a.get("disambiguation", ""))
for a in res.get("artist-list", [])
]
def browse_release_groups(self, artist_mbid: str) -> list[ReleaseGroupInfo]:
mb = self._ua()
out: list[ReleaseGroupInfo] = []
offset = 0
while True:
res = mb.browse_release_groups(artist=artist_mbid, limit=100, offset=offset)
groups = res.get("release-group-list", [])
for g in groups:
out.append(
ReleaseGroupInfo(
rg_mbid=g["id"],
title=g.get("title", ""),
primary_type=g.get("primary-type", "") or "",
secondary_types=tuple(g.get("secondary-type-list", []) or ()),
first_release_date=g.get("first-release-date", "") or "",
)
)
offset += len(groups)
if len(groups) < 100 or offset >= int(res.get("release-group-count", offset)):
break
return out