feat: add configurable UICoverArtSize option

Converted the hardcoded UICoverArtSize constant (600px) into a
configurable option, allowing users to reduce the cover art size
requested by the UI to mitigate slow image encoding. The value is
served to the frontend via the app config and used by all components
that request cover art. Also simplified the cache warmer by removing
a single-iteration loop in favor of direct code.

core/artwork/cache_warmer.go

@@ -10,7 +10,6 @@ import (
 	"time"
 
 	"github.com/navidrome/navidrome/conf"
-	"github.com/navidrome/navidrome/consts"
 	"github.com/navidrome/navidrome/log"
 	"github.com/navidrome/navidrome/model"
 	"github.com/navidrome/navidrome/model/request"
@@ -24,7 +23,7 @@ type CacheWarmer interface {
 
 // NewCacheWarmer creates a new CacheWarmer instance. The CacheWarmer will pre-cache Artwork images in the background
 // to speed up the response time when the image is requested by the UI. The cache is pre-populated with the original
-// image size, as well as the size defined in the UICoverArtSize constant.
+// image size, as well as the size defined by the UICoverArtSize config option.
 func NewCacheWarmer(artwork Artwork, cache cache.FileCache) CacheWarmer {
 	// If image cache is disabled, return a NOOP implementation
 	if conf.Server.ImageCacheSize == "0" || !conf.Server.EnableArtworkPrecache {
@@ -142,16 +141,14 @@ func (a *cacheWarmer) doCacheImage(ctx context.Context, id model.ArtworkID) erro
 	ctx, cancel := context.WithTimeout(ctx, 10*time.Second)
 	defer cancel()
 
-	for _, size := range consts.CacheWarmerImageSizes {
-		r, _, err := a.artwork.Get(ctx, id, size, true)
-		if err != nil {
-			return fmt.Errorf("caching id='%s', size=%d: %w", id, size, err)
-		}
-		_, err = io.Copy(io.Discard, r)
-		r.Close()
-		return err
+	size := conf.Server.UICoverArtSize
+	r, _, err := a.artwork.Get(ctx, id, size, true)
+	if err != nil {
+		return fmt.Errorf("caching id='%s', size=%d: %w", id, size, err)
 	}
-	return nil
+	_, err = io.Copy(io.Discard, r)
+	r.Close()
+	return err
 }
 
 func NoopCacheWarmer() CacheWarmer {

core/artwork/cache_warmer_test.go

@@ -12,7 +12,6 @@ import (
 
 	"github.com/navidrome/navidrome/conf"
 	"github.com/navidrome/navidrome/conf/configtest"
-	"github.com/navidrome/navidrome/consts"
 	"github.com/navidrome/navidrome/model"
 	"github.com/navidrome/navidrome/utils/cache"
 	. "github.com/onsi/ginkgo/v2"
@@ -182,7 +181,7 @@ var _ = Describe("CacheWarmer", func() {
 
 			Eventually(func() []int {
 				return aw.getCachedSizes()
-			}).Should(ContainElements(consts.UICoverArtSize))
+			}).Should(ContainElements(conf.Server.UICoverArtSize))
 		})
 	})
 })

core/metrics/insights.go

@@ -196,6 +196,7 @@ var staticData = sync.OnceValue(func() insights.Data {
 	data.Config.EnableArtworkUpload = conf.Server.EnableArtworkUpload
 	data.Config.CoverArtQuality = conf.Server.CoverArtQuality
 	data.Config.EnableWebPEncoding = conf.Server.EnableWebPEncoding
+	data.Config.UICoverArtSize = conf.Server.UICoverArtSize
 	data.Config.EnableCoverAnimation = conf.Server.EnableCoverAnimation
 	data.Config.EnableNowPlaying = conf.Server.EnableNowPlaying
 	data.Config.EnableDownloads = conf.Server.EnableDownloads

core/metrics/insights/data.go

@@ -66,6 +66,7 @@ type Data struct {
 		EnableArtworkUpload     bool   `json:"enableArtworkUpload,omitempty"`
 		CoverArtQuality         int    `json:"coverArtQuality,omitempty"`
 		EnableWebPEncoding      bool   `json:"enableWebPEncoding,omitempty"`
+		UICoverArtSize          int    `json:"uiCoverArtSize,omitempty"`
 		EnableCoverAnimation    bool   `json:"enableCoverAnimation,omitempty"`
 		EnableNowPlaying        bool   `json:"enableNowPlaying,omitempty"`
 		SessionTimeout          uint64 `json:"sessionTimeout,omitempty"`