chore: custom error

internal/components/images/controller.go

@@ -3,10 +3,20 @@ package images
 import (
 	"bytes"
 	"context"
+	"encoding/base64"
+	"encoding/binary"
 	"errors"
 	"fmt"
+	"hash/fnv"
+	"image"
+	"image/jpeg"
+	_ "image/jpeg"
+	_ "image/png"
 	"io"
 	"strings"
+	"time"
+
+	"github.com/valkey-io/valkey-go"
 )
 
 var ErrNotAnImage = errors.New("not an image")
@@ -24,7 +34,7 @@ func (s *Service) getMime(path string) (mimeType string, err error) {
 	return
 }
 
-func (s *Service) GetImage(ctx context.Context, uid string) (img io.Reader, mimeType string, err error) {
+func (s *Service) getImage(uid string) (file []byte, mimeType string, err error) {
 	path, err := PathFromUID(uid)
 	if err != nil {
 		err = fmt.Errorf("could not get path: %w", err)
@@ -40,10 +50,69 @@ func (s *Service) GetImage(ctx context.Context, uid string) (img io.Reader, mime
 		return
 	}
 
-	file, err := s.fs.Read(path)
+	file, err = s.fs.Read(path)
 	if err != nil {
 		err = fmt.Errorf("image file could not be fetched")
 	}
 
-	return bytes.NewBuffer(file), mimeType, err
+	return
+}
+
+func (s *Service) GetImage(ctx context.Context, uid string, options Options) (img io.Reader, mimeType string, err error) {
+	rawImage, mimeType, err := s.getImage(uid)
+	if err != nil {
+		return
+	}
+
+	hash, err := hash(rawImage, options)
+	if err != nil {
+		return
+	}
+
+	if imgBytes, err := s.cache.Do(ctx, s.cache.B().Get().Key("img:"+hash).Build()).AsBytes(); err == nil {
+		return bytes.NewBuffer(imgBytes), mimeType, err
+	}
+
+	decImage, _, err := image.Decode(bytes.NewBuffer(rawImage))
+	if err != nil {
+		return
+	}
+
+	decImage = scale(decImage, options)
+	outBuff := bytes.NewBuffer(make([]byte, 0, 1024))
+
+	if options.Quality == 0 {
+		options.Quality = 80
+	}
+
+	err = jpeg.Encode(outBuff, decImage, &jpeg.Options{Quality: options.Quality})
+	if err != nil {
+		return
+	}
+	if err = s.cache.Do(ctx, s.cache.B().Set().Key("img:"+hash).Value(valkey.BinaryString(outBuff.Bytes())).Ex(time.Hour*48).Build()).Error(); err == nil {
+		return outBuff, "image/jpeg", err
+	}
+
+	return outBuff, "image/jpeg", err
+}
+
+func hash(bytes []byte, options Options) (hash string, err error) {
+	h := fnv.New128()
+
+	if _, err = h.Write(bytes); err != nil {
+		return
+	}
+	if err = binary.Write(h, binary.LittleEndian, int64(options.Height)); err != nil {
+		return
+	}
+	if err = binary.Write(h, binary.LittleEndian, int64(options.Width)); err != nil {
+		return
+	}
+	if err = binary.Write(h, binary.LittleEndian, int64(options.Quality)); err != nil {
+		return
+	}
+
+	res := h.Sum(make([]byte, 0, 128/8))
+
+	return base64.RawStdEncoding.EncodeToString(res), nil
 }