Use LB API to lookup missing metadata for loves

This is faster than using the MBID API individually

internal/backends/lbarchive/lbarchive.go

@@ -36,11 +36,12 @@ import (
 
 const (
 	listensBatchSize = 2000
-	lovesBatchSize   = 10
+	lovesBatchSize   = listenbrainz.MaxItemsPerGet
 )
 
 type ListenBrainzArchiveBackend struct {
 	filePath string
+	lbClient listenbrainz.Client
 	mbClient musicbrainzws2.Client
 }
 
@@ -56,6 +57,7 @@ func (b *ListenBrainzArchiveBackend) Options() []models.BackendOption {
 
 func (b *ListenBrainzArchiveBackend) InitConfig(config *config.ServiceConfig) error {
 	b.filePath = config.GetString("file-path")
+	b.lbClient = listenbrainz.NewClient("", version.UserAgent())
 	b.mbClient = *musicbrainzws2.NewClient(musicbrainzws2.AppInfo{
 		Name:    version.AppName,
 		Version: version.AppVersion,
@@ -164,7 +166,7 @@ func (b *ListenBrainzArchiveBackend) ExportLoves(
 		return
 	}
 
-	loves := make(models.LovesList, 0, lovesBatchSize)
+	batch := make([]listenbrainz.Feedback, 0, lovesBatchSize)
 	for feedback, err := range archive.IterFeedback(oldestTimestamp) {
 		if err != nil {
 			p.Export.Abort()
@@ -173,37 +175,43 @@ func (b *ListenBrainzArchiveBackend) ExportLoves(
 			return
 		}
 
-		// The export file does not include track metadata. Try fetching details
-		// from MusicBrainz.
-		if feedback.TrackMetadata == nil {
-			track, err := lbapi.LookupRecording(ctx, &b.mbClient, feedback.RecordingMBID)
-			if err == nil {
-				feedback.TrackMetadata = track
-			}
+		if feedback.UserName == "" {
+			feedback.UserName = userInfo.Name
 		}
 
-		love := lbapi.AsLove(feedback)
-		if love.UserName == "" {
-			love.UserName = userInfo.Name
-		}
-		// TODO: The dump does not contain TrackMetadata for feedback.
-		// We need to look it up in the archive.
-		loves = append(loves, love)
+		batch = append(batch, feedback)
 
 		// Update the progress
 		p.Export.TotalItems += 1
-		remainingTime := startTime.Sub(love.Created)
+		remainingTime := startTime.Sub(time.Unix(feedback.Created, 0))
 		p.Export.Elapsed = int64(totalDuration.Seconds() - remainingTime.Seconds())
 
 		// Allow the importer to start processing the listens by
 		// sending them in batches.
-		if len(loves) >= lovesBatchSize {
+		if len(batch) >= lovesBatchSize {
+			// The dump does not contain track metadata. Extend it with additional
+			// lookups
+			loves, err := lbapi.ExtendTrackMetadata(ctx, &b.lbClient, &b.mbClient, &batch)
+			if err != nil {
+				p.Export.Abort()
+				progress <- p
+				results <- models.LovesResult{Error: err}
+				return
+			}
+
 			results <- models.LovesResult{Items: loves}
 			progress <- p
-			loves = loves[:0]
+			batch = batch[:0]
 		}
 	}
 
+	loves, err := lbapi.ExtendTrackMetadata(ctx, &b.lbClient, &b.mbClient, &batch)
+	if err != nil {
+		p.Export.Abort()
+		progress <- p
+		results <- models.LovesResult{Error: err}
+		return
+	}
 	results <- models.LovesResult{Items: loves}
 	p.Export.Complete()
 	progress <- p

internal/backends/listenbrainz/helper.go

@@ -32,35 +32,6 @@ import (
 	"go.uploadedlobster.com/scotty/internal/models"
 )
 
-func LookupRecording(
-	ctx context.Context,
-	mb *musicbrainzws2.Client,
-	mbid mbtypes.MBID,
-) (*listenbrainz.Track, error) {
-	filter := musicbrainzws2.IncludesFilter{
-		Includes: []string{"artist-credits"},
-	}
-	recording, err := mb.LookupRecording(ctx, mbid, filter)
-	if err != nil {
-		return nil, err
-	}
-
-	artistMBIDs := make([]mbtypes.MBID, 0, len(recording.ArtistCredit))
-	for _, artist := range recording.ArtistCredit {
-		artistMBIDs = append(artistMBIDs, artist.Artist.ID)
-	}
-	track := listenbrainz.Track{
-		TrackName:  recording.Title,
-		ArtistName: recording.ArtistCredit.String(),
-		MBIDMapping: &listenbrainz.MBIDMapping{
-			// In case of redirects this MBID differs from the looked up MBID
-			RecordingMBID: recording.ID,
-			ArtistMBIDs:   artistMBIDs,
-		},
-	}
-	return &track, nil
-}
-
 func AsListen(lbListen listenbrainz.Listen) models.Listen {
 	listen := models.Listen{
 		ListenedAt: time.Unix(lbListen.ListenedAt, 0),
@@ -113,3 +84,107 @@ func AsTrack(t listenbrainz.Track) models.Track {
 
 	return track
 }
+
+func LookupRecording(
+	ctx context.Context,
+	mb *musicbrainzws2.Client,
+	mbid mbtypes.MBID,
+) (*listenbrainz.Track, error) {
+	filter := musicbrainzws2.IncludesFilter{
+		Includes: []string{"artist-credits"},
+	}
+	recording, err := mb.LookupRecording(ctx, mbid, filter)
+	if err != nil {
+		return nil, err
+	}
+
+	artistMBIDs := make([]mbtypes.MBID, 0, len(recording.ArtistCredit))
+	for _, artist := range recording.ArtistCredit {
+		artistMBIDs = append(artistMBIDs, artist.Artist.ID)
+	}
+	track := listenbrainz.Track{
+		TrackName:  recording.Title,
+		ArtistName: recording.ArtistCredit.String(),
+		MBIDMapping: &listenbrainz.MBIDMapping{
+			// In case of redirects this MBID differs from the looked up MBID
+			RecordingMBID: recording.ID,
+			ArtistMBIDs:   artistMBIDs,
+		},
+	}
+	return &track, nil
+}
+
+func ExtendTrackMetadata(
+	ctx context.Context,
+	lb *listenbrainz.Client,
+	mb *musicbrainzws2.Client,
+	feedbacks *[]listenbrainz.Feedback,
+) ([]models.Love, error) {
+	mbids := make([]mbtypes.MBID, 0, len(*feedbacks))
+	for _, feedback := range *feedbacks {
+		if feedback.TrackMetadata == nil && feedback.RecordingMBID != "" {
+			mbids = append(mbids, feedback.RecordingMBID)
+		}
+	}
+	result, err := lb.MetadataRecordings(ctx, mbids)
+	if err != nil {
+		return nil, err
+	}
+
+	loves := make([]models.Love, 0, len(*feedbacks))
+	for _, feedback := range *feedbacks {
+		if feedback.TrackMetadata == nil && feedback.RecordingMBID != "" {
+			metadata, ok := result[feedback.RecordingMBID]
+			if ok {
+				feedback.TrackMetadata = trackFromMetadataLookup(
+					feedback.RecordingMBID, metadata)
+			} else {
+				// MBID not in result. This is probably a MBID redirect, get
+				// data from MB instead (slower).
+				// If this also fails, just leave the metadata empty.
+				track, err := LookupRecording(ctx, mb, feedback.RecordingMBID)
+				if err == nil {
+					feedback.TrackMetadata = track
+				}
+			}
+		}
+
+		loves = append(loves, AsLove(feedback))
+	}
+
+	return loves, nil
+}
+
+func trackFromMetadataLookup(
+	recordingMBID mbtypes.MBID,
+	metadata listenbrainz.RecordingMetadata,
+) *listenbrainz.Track {
+	artistMBIDs := make([]mbtypes.MBID, 0, len(metadata.Artist.Artists))
+	artists := make([]listenbrainz.Artist, 0, len(metadata.Artist.Artists))
+	for _, artist := range metadata.Artist.Artists {
+		artistMBIDs = append(artistMBIDs, artist.ArtistMBID)
+		artists = append(artists, listenbrainz.Artist{
+			ArtistCreditName: artist.Name,
+			ArtistMBID:       artist.ArtistMBID,
+			JoinPhrase:       artist.JoinPhrase,
+		})
+	}
+
+	return &listenbrainz.Track{
+		TrackName:   metadata.Recording.Name,
+		ArtistName:  metadata.Artist.Name,
+		ReleaseName: metadata.Release.Name,
+		AdditionalInfo: map[string]any{
+			"duration_ms":        metadata.Recording.Length,
+			"release_group_mbid": metadata.Release.ReleaseGroupMBID,
+		},
+		MBIDMapping: &listenbrainz.MBIDMapping{
+			RecordingMBID:  recordingMBID,
+			ReleaseMBID:    metadata.Release.MBID,
+			ArtistMBIDs:    artistMBIDs,
+			Artists:        artists,
+			CAAID:          metadata.Release.CAAID,
+			CAAReleaseMBID: metadata.Release.CAAReleaseMBID,
+		},
+	}
+}