resources/image: Add some image decode/encode debug logging

common/loggers/logger.go

@@ -173,6 +173,7 @@ func LevelLoggerToWriter(l logg.LevelLogger) io.Writer {
 
 type Logger interface {
 	Debug() logg.LevelLogger
+	DebugCommand(command string) logg.LevelLogger
 	Debugf(format string, v ...any)
 	Debugln(v ...any)
 	Error() logg.LevelLogger
@@ -221,6 +222,10 @@ func (l *logAdapter) Debug() logg.LevelLogger {
 	return l.debugl
 }
 
+func (l *logAdapter) DebugCommand(command string) logg.LevelLogger {
+	return l.debugl.WithField(FieldNameCmd, command)
+}
+
 func (l *logAdapter) Debugf(format string, v ...any) {
 	l.debugl.Logf(format, v...)
 }

resources/images/codec.go

@@ -27,6 +27,7 @@ import (
 	"io"
 
 	"github.com/bep/imagemeta"
+	"github.com/bep/logg"
 	"github.com/gohugoio/hugo/common/himage"
 	"golang.org/x/image/bmp"
 	"golang.org/x/image/tiff"
@@ -56,14 +57,23 @@ type EncodeDecoder interface {
 
 // Codec is a generic image codec supporting multiple formats.
 type Codec struct {
-	webp EncodeDecoder
+	webp   EncodeDecoder
+	debugl logg.LevelLogger
 }
 
-func newCodec(webp EncodeDecoder) *Codec {
-	return &Codec{webp: webp}
+func newCodec(webp EncodeDecoder, debugl logg.LevelLogger) *Codec {
+	return &Codec{webp: webp, debugl: debugl}
 }
 
 func (d *Codec) EncodeTo(conf ImageConfig, w io.Writer, img image.Image) error {
+	d.debugl.Log(
+		// This construct looks odd, but the func will only be called if debug is enabled.
+		logg.StringFunc(
+			func() string {
+				return fmt.Sprintf("Encoding image to format %s with config %+v", conf.TargetFormat, conf)
+			},
+		),
+	)
 	switch conf.TargetFormat {
 	case JPEG:
 		var rgba *image.RGBA
@@ -144,6 +154,13 @@ func (d *Codec) EncodeTo(conf ImageConfig, w io.Writer, img image.Image) error {
 }
 
 func (d *Codec) DecodeFormat(f Format, r io.Reader) (image.Image, error) {
+	d.debugl.Log(
+		logg.StringFunc(
+			func() string {
+				return fmt.Sprintf("Decoding image from format %s", f)
+			},
+		),
+	)
 	switch f {
 	case JPEG, PNG:
 		// We reworked this decode/encode setup to get full WebP support in v0.153.0.
@@ -192,6 +209,13 @@ func (d *Codec) DecodeFormat(f Format, r io.Reader) (image.Image, error) {
 }
 
 func (d *Codec) Decode(r io.Reader) (image.Image, error) {
+	d.debugl.Log(
+		logg.StringFunc(
+			func() string {
+				return "Decoding image from unknown format"
+			},
+		),
+	)
 	rr := toPeekReader(r)
 	format, err := formatFromImage(rr)
 	if err != nil {

resources/images/image.go

@@ -124,7 +124,7 @@ func (i *Image) initConfig() error {
 	return nil
 }
 
-func NewImageProcessor(warnl logg.LevelLogger, wasmDispatchers *warpc.Dispatchers, cfg *config.ConfigNamespace[ImagingConfig, ImagingConfigInternal]) (*ImageProcessor, error) {
+func NewImageProcessor(debugl, warnl logg.LevelLogger, wasmDispatchers *warpc.Dispatchers, cfg *config.ConfigNamespace[ImagingConfig, ImagingConfigInternal]) (*ImageProcessor, error) {
 	e := cfg.Config.Imaging.Exif
 	exifDecoder, err := meta.NewDecoder(
 		meta.WithDateDisabled(e.DisableDate),
@@ -154,7 +154,7 @@ func NewImageProcessor(warnl logg.LevelLogger, wasmDispatchers *warpc.Dispatcher
 	if webpCodec == nil {
 		return nil, errors.New("webp codec is not available")
 	}
-	imageCodec := newCodec(webpCodec)
+	imageCodec := newCodec(webpCodec, debugl)
 
 	return &ImageProcessor{
 		Cfg:         cfg,

resources/resource_spec.go

@@ -62,9 +62,10 @@ func NewSpec(
 	conf := s.Cfg.GetConfig().(*allconfig.Config)
 	imgConfig := conf.Imaging
 
+	imagesDebugl := logger.DebugCommand("images")
 	imagesWarnl := logger.WarnCommand("images")
 
-	imaging, err := images.NewImageProcessor(imagesWarnl, wasmDispatchers, imgConfig)
+	imaging, err := images.NewImageProcessor(imagesDebugl, imagesWarnl, wasmDispatchers, imgConfig)
 	if err != nil {
 		return nil, err
 	}