feat(discovery): derive core-album suggestions for surfaced artists

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

worker/lyra_worker/discovery.py

@@ -3,6 +3,7 @@ from dataclasses import dataclass
 import psycopg
 
 from lyra_worker.browser import MbBrowser
+from lyra_worker.release_filter import is_core_release
 from lyra_worker.similarity.base import SimilaritySource
 
 _TRUE = {"1", "true", "yes", "on"}
@@ -82,9 +83,50 @@ def _upsert_artist(conn: psycopg.Connection, cand: dict) -> int:
         return cur.rowcount
 
 
+def _existing_rg_mbids(conn: psycopg.Connection) -> set[str]:
+    with conn.cursor() as cur:
+        cur.execute('SELECT "rgMbid" FROM "MonitoredRelease"')
+        return {r[0] for r in cur.fetchall()}
+
+
+def _upsert_album(conn: psycopg.Connection, artist: dict, rg) -> int:
+    dedupe = f"album:{artist['mbid']}:{rg.rg_mbid}"
+    with conn.cursor() as cur:
+        cur.execute(
+            'INSERT INTO "DiscoverySuggestion" (id, kind, "artistMbid", "artistName", '
+            '"rgMbid", album, "primaryType", "secondaryTypes", "firstReleaseDate", '
+            'score, "seedCount", sources, status, "dedupeKey", "createdAt", "updatedAt") '
+            "VALUES (gen_random_uuid()::text, 'album', %s, %s, %s, %s, %s, %s, %s, %s, %s, %s, "
+            "'pending', %s, now(), now()) "
+            'ON CONFLICT ("dedupeKey") DO UPDATE SET score = EXCLUDED.score, '
+            '"updatedAt" = now() '
+            "WHERE \"DiscoverySuggestion\".status = 'pending'",
+            (artist["mbid"], artist["name"], rg.rg_mbid, rg.title,
+             rg.primary_type or None, list(rg.secondary_types), rg.first_release_date or None,
+             artist["score"], artist["seed_count"], sorted(artist["sources"]), dedupe),
+        )
+        return cur.rowcount
+
+
 def _derive_albums(conn: psycopg.Connection, browser: MbBrowser, surfaced: list[dict],
                    cfg: DiscoveryConfig) -> int:
-    return 0  # replaced in the album-derivation task
+    if cfg.albums_per_artist <= 0:
+        return 0
+    have = _existing_rg_mbids(conn)
+    albums = 0
+    for artist in surfaced:
+        try:
+            groups = browser.browse_release_groups(artist["mbid"])
+        except Exception as e:  # one artist's browse failure must not abort the sweep
+            print(f"worker: discovery album browse failed for {artist['mbid']}: {e}", flush=True)
+            continue
+        core = [g for g in groups
+                if is_core_release(g.primary_type, g.secondary_types) and g.rg_mbid not in have]
+        core.sort(key=lambda g: g.first_release_date or "", reverse=True)
+        for rg in core[: cfg.albums_per_artist]:
+            albums += _upsert_album(conn, artist, rg)
+            have.add(rg.rg_mbid)
+    return albums
 
 
 def run_discovery(conn: psycopg.Connection, sources: list[SimilaritySource],

worker/lyra_worker/release_filter.py

@@ -0,0 +1,6 @@
+_CORE_PRIMARY = {"Album", "Single", "EP"}
+
+
+def is_core_release(primary_type: str, secondary_types) -> bool:
+    """A 'core' studio release: Album/Single/EP with no secondary types (live, comp, etc.)."""
+    return (primary_type or "") in _CORE_PRIMARY and len(secondary_types or ()) == 0