Files
minstrel/internal/sync/changes.go
T
bvandeusen 0fa7dc7982 feat(server): scanner + DeleteTrackFile write library_changes
Wires sync.LogChange into the library mutation sites so /api/library/sync
reflects upserts and deletes.

Architectural pivot: LogChange's signature is now (ctx, dbq.DBTX, ...) so
it works with both *pgxpool.Pool and pgx.Tx. The scanner doesn't run
mutations in explicit transactions, so it pool-binds; delete.go matches.
Tx-bound callers (likes/playlists in subsequent commits) keep atomicity.

Also: sync.FormatUUID centralizes the pgtype.UUID → canonical string
conversion that both the scanner and the sync handler need; library_sync.go
now uses it instead of a local copy.

Best-effort logging on scanner failures (Warn, don't fail the scan): a
LogChange error after a successful upsert is rare and self-healing — the
next scan that touches the entity re-emits the change.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
2026-05-09 22:39:58 -04:00

76 lines
2.4 KiB
Go

package sync
import (
"context"
"fmt"
"github.com/jackc/pgx/v5/pgtype"
"git.fabledsword.com/bvandeusen/minstrel/internal/db/dbq"
)
// LogChange writes a row to library_changes via the supplied DBTX. dbq.DBTX
// is satisfied by both *pgxpool.Pool and pgx.Tx, so callers can opt into
// transactional safety where they already hold a tx, or pool-bind for
// best-effort logging when no tx is available.
//
// Callers SHOULD pass a tx that owns the underlying mutation — the change
// row and the mutation then commit or roll back together. When pool-bound,
// the scanner-style "log after success" pattern keeps the log consistent
// with reality at the cost of a tiny race window: if the LogChange call
// itself fails after the mutation succeeded, that mutation won't appear in
// the change log until the entity is touched again.
//
// entityID is the string form of the row's primary key. For composite-key
// entities (likes, playlist_tracks), use EncodeLikeID / EncodePlaylistTrackID
// to produce stable strings. For pgtype.UUID values, use FormatUUID.
func LogChange(ctx context.Context, dbtx dbq.DBTX, entityType EntityType, entityID string, op Op) error {
q := dbq.New(dbtx)
if err := q.InsertLibraryChange(ctx, dbq.InsertLibraryChangeParams{
EntityType: string(entityType),
EntityID: entityID,
Op: string(op),
}); err != nil {
return fmt.Errorf("sync.LogChange(%s, %s, %s): %w", entityType, entityID, op, err)
}
return nil
}
// FormatUUID renders a pgtype.UUID as the canonical 8-4-4-4-12 hex form.
// Returns "" if the UUID is not valid.
func FormatUUID(u pgtype.UUID) string {
if !u.Valid {
return ""
}
return formatUUIDBytes(u.Bytes)
}
func formatUUIDBytes(b [16]byte) string {
const hex = "0123456789abcdef"
out := make([]byte, 36)
pos := 0
for i := 0; i < 16; i++ {
if i == 4 || i == 6 || i == 8 || i == 10 {
out[pos] = '-'
pos++
}
out[pos] = hex[b[i]>>4]
out[pos+1] = hex[b[i]&0x0f]
pos += 2
}
return string(out)
}
// EncodeLikeID joins a user UUID and an entity UUID into the stable
// composite identifier used for like_* rows in library_changes. Both
// sides are UUID strings so no escaping is needed.
func EncodeLikeID(userID, entityID string) string {
return userID + ":" + entityID
}
// EncodePlaylistTrackID joins a playlist UUID and a track UUID into the
// stable composite identifier used for playlist_track rows.
func EncodePlaylistTrackID(playlistID, trackID string) string {
return playlistID + ":" + trackID
}