Added size parameter to getCoverArt.view endpoint

.gopmfile

@@ -8,6 +8,7 @@ github.com/siddontang/ledisdb = commit:713b229
 github.com/smartystreets/goconvey = commit:899ed5a
 github.com/karlkfi/inject = commit:fe06da2
 github.com/dhowden/tag = commit:bccc91e
+github.com/nfnt/resize = commit:4d93a29
 
 [res]
 include = conf

.travis.yml

@@ -15,6 +15,7 @@ install:
   - go get github.com/karlkfi/inject
   - go get github.com/smartystreets/goconvey
   - go get github.com/dhowden/tag
+  - go get github.com/nfnt/resize
 
 script:
   - go test ./... -v

api/get_cover_art.go

@@ -17,11 +17,11 @@ func (c *GetCoverArtController) Prepare() {
 	inject.ExtractAssignable(utils.Graph, &c.cover)
 }
 
-// TODO accept size parameter
 func (c *GetCoverArtController) Get() {
 	id := c.RequiredParamString("id", "id parameter required")
+	size := c.ParamInt("size")
 
-	err := c.cover.GetCover(id, 0, c.Ctx.ResponseWriter)
+	err := c.cover.Get(id, size, c.Ctx.ResponseWriter)
 
 	switch {
 	case err == engine.DataNotFound:

api/get_cover_art_test.go

@@ -3,16 +3,17 @@ package api_test
 import (
 	"testing"
 
+	"fmt"
+	"net/http"
+	"net/http/httptest"
+
+	"github.com/astaxie/beego"
 	"github.com/deluan/gosonic/api/responses"
 	"github.com/deluan/gosonic/domain"
 	. "github.com/deluan/gosonic/tests"
 	"github.com/deluan/gosonic/tests/mocks"
 	"github.com/deluan/gosonic/utils"
 	. "github.com/smartystreets/goconvey/convey"
-	"net/http"
-	"net/http/httptest"
-	"github.com/astaxie/beego"
-	"fmt"
 )
 
 func getCoverArt(params ...string) (*http.Request, *httptest.ResponseRecorder) {
@@ -52,6 +53,13 @@ func TestGetCoverArt(t *testing.T) {
 			So(w.Body.Bytes(), ShouldMatchMD5, "e859a71cd1b1aaeb1ad437d85b306668")
 			So(w.Header().Get("Content-Type"), ShouldEqual, "image/jpeg")
 		})
+		Convey("When specifying a size", func() {
+			mockMediaFileRepo.SetData(`[{"Id":"2","HasCoverArt":true,"Path":"tests/fixtures/01 Invisible (RED) Edit Version.mp3"}]`, 1)
+			_, w := getCoverArt("id=2", "size=100")
+
+			So(w.Body.Bytes(), ShouldMatchMD5, "04378f523ca3e8ead33bf7140d39799e")
+			So(w.Header().Get("Content-Type"), ShouldEqual, "image/jpeg")
+		})
 		Reset(func() {
 			mockMediaFileRepo.SetData("[]", 0)
 			mockMediaFileRepo.SetError(false)

engine/cover.go

@@ -2,15 +2,23 @@ package engine
 
 import (
 	"io"
-	"io/ioutil"
 	"os"
 
+	"image"
+	_ "image/gif"
+	_ "image/jpeg"
+	_ "image/png"
+
+	"bytes"
+	"image/jpeg"
+
 	"github.com/deluan/gosonic/domain"
 	"github.com/dhowden/tag"
+	"github.com/nfnt/resize"
 )
 
 type Cover interface {
-	GetCover(id string, size int, out io.Writer) error
+	Get(id string, size int, out io.Writer) error
 }
 
 type cover struct {
@@ -21,29 +29,48 @@ func NewCover(mr domain.MediaFileRepository) Cover {
 	return cover{mr}
 }
 
-func (c cover) GetCover(id string, size int, out io.Writer) error {
+func (c cover) Get(id string, size int, out io.Writer) error {
 	mf, err := c.mfileRepo.Get(id)
 	if err != nil {
 		return err
 	}
 
-	var img []byte
+	var reader io.Reader
 
 	if mf != nil && mf.HasCoverArt {
-		img, err = readFromTag(mf.Path)
+		reader, err = readFromTag(mf.Path)
 	} else {
-		img, err = ioutil.ReadFile("static/default_cover.jpg")
+		f, err := os.Open("static/default_cover.jpg")
+		if err == nil {
+			defer f.Close()
+			reader = f
+		}
 	}
 
 	if err != nil {
 		return DataNotFound
 	}
 
-	_, err = out.Write(img)
+	if size > 0 {
-	return err
+		return resizeImage(reader, size, out)
+	} else {
+		_, err = io.Copy(out, reader)
+		return err
+	}
+
 }
 
-func readFromTag(path string) ([]byte, error) {
+func resizeImage(reader io.Reader, size int, out io.Writer) error {
+	img, _, err := image.Decode(reader)
+	if err != nil {
+		return err
+	}
+
+	m := resize.Resize(uint(size), 0, img, resize.NearestNeighbor)
+	return jpeg.Encode(out, m, &jpeg.Options{Quality: 75})
+}
+
+func readFromTag(path string) (io.Reader, error) {
 	f, err := os.Open(path)
 	if err != nil {
 		return nil, err
@@ -55,5 +82,5 @@ func readFromTag(path string) ([]byte, error) {
 		return nil, err
 	}
 
-	return m.Picture().Data, nil
+	return bytes.NewReader(m.Picture().Data), nil
 }