kadai1: make image converter

kadai1/sh-tatsuno/gophoto/conv/img.go

@@ -0,0 +1,109 @@
+package conv
+
+import (
+	"image"
+	"image/gif"  // import gif
+	"image/jpeg" // import jpeg
+	"image/png"  // import png
+	"os"
+	"path/filepath"
+
+	"golang.org/x/xerrors"
+)
+
+// Img image struct
+type Img struct {
+	Path string
+	Data image.Image
+}
+
+// NewImg generate Img struct
+func NewImg(path string) (*Img, error) {
+	file, err := os.Open(path)
+	defer file.Close()
+	if err != nil {
+		return nil, err
+	}
+	img, _, err := image.Decode(file)
+	if err != nil {
+		return nil, err
+	}
+	return &Img{
+		Path: path,
+		Data: img,
+	}, nil
+}
+
+// Save save img for input format if format satisfies ".jpeg", ".jpg", ".gif", ".png"
+func (i *Img) Save(path string) error {
+	ext := filepath.Ext(path)
+	var err error
+	err = func(ext string) error {
+		for _, postfix := range []string{".jpeg", ".jpg", ".gif", ".png"} {
+			if ext == postfix {
+				return nil
+			}
+		}
+		return xerrors.New("invalid extension")
+	}(ext)
+	if err != nil {
+		return err
+	}
+
+	// if file exist, do nothing
+	if _, err := os.Stat(path); !os.IsNotExist(err) {
+		return nil
+	}
+
+	dst, err := os.Create(path)
+	if err != nil {
+		return err
+	}
+	defer dst.Close()
+
+	switch ext {
+	case ".jpeg", ".jpg":
+		err = jpeg.Encode(dst, i.Data, nil)
+	case ".gif":
+		err = gif.Encode(dst, i.Data, nil)
+	case ".png":
+		err = png.Encode(dst, i.Data)
+	default:
+		err = xerrors.New("error in main method")
+	}
+	return err
+}
+
+// AddExt add extension
+func (i *Img) AddExt(ext string) string {
+	return i.Path + ext
+}
+
+// Replace replace image
+func (i *Img) Replace(ext string) error {
+
+	// check path
+	prevPath := i.Path
+	if filepath.Ext(prevPath) == ext {
+		return nil
+	}
+
+	// save file
+	newPath := prevPath[:len(prevPath)-len(filepath.Ext(prevPath))] + ext
+
+	// if file exist, do nothing
+	if _, err := os.Stat(newPath); !os.IsNotExist(err) {
+		return nil
+	}
+
+	if err := i.Save(newPath); err != nil {
+		return err
+	}
+
+	// remove old file
+	if err := os.Remove(prevPath); err != nil {
+		return err
+	}
+	i.Path = newPath
+	return nil
+}

kadai1/sh-tatsuno/gophoto/conv/img_test.go

@@ -0,0 +1,85 @@
+package conv
+
+import (
+	"image/jpeg"
+	"image/png"
+	"os"
+	"testing"
+)
+
+func Test_Img(t *testing.T) {
+	t.Run("OK: .png -> .jpeg", func(t *testing.T) {
+
+		// ### Given ###
+		img, err := NewImg("./lena.jpeg")
+		if err != nil {
+			t.Fatalf("Cannot load file. err: %v", err)
+		}
+
+		// ### When ###
+		path := "./lena-png.jpeg"
+		if err = img.Save(path); err != nil {
+			t.Fatalf("Cannot save file. err: %v", err)
+		}
+
+		// ### Then ###
+		file, err := os.Open(path)
+		if err != nil {
+			t.Fatalf("Cannot open saved file. err: %v", err)
+		}
+		if _, err = jpeg.Decode(file); err != nil {
+			t.Fatalf("Cannot decode saved file. err: %v", err)
+		}
+		if err := os.Remove(path); err != nil {
+			t.Fatalf("Cannot remove saved file. err: %v", err)
+		}
+
+	})
+
+	t.Run("OK: .jpeg -> .png", func(t *testing.T) {
+
+		// ### Given ###
+		img, err := NewImg("./lena.png")
+		if err != nil {
+			t.Fatalf("Cannot load file. err: %v", err)
+		}
+
+		// ### When ###
+		path := "./lena-jpeg.png"
+		if err = img.Save(path); err != nil {
+			t.Fatalf("Cannot save file. err: %v", err)
+		}
+
+		// ### Then ###
+		file, err := os.Open(path)
+		if err != nil {
+			t.Fatalf("Cannot open saved file. err: %v", err)
+		}
+		if _, err = png.Decode(file); err != nil {
+			t.Fatalf("Cannot decode saved file. err: %v", err)
+		}
+		if err := os.Remove(path); err != nil {
+			t.Fatalf("Cannot remove saved file. err: %v", err)
+		}
+
+	})
+
+	t.Run("NG: cannot openfile", func(t *testing.T) {
+
+		// ### Given ###
+		_, err := NewImg("./noexist.png")
+		if err == nil {
+			t.Fatal("Load no exist file.")
+		}
+	})
+
+	t.Run("NG: invalid extension", func(t *testing.T) {
+
+		// ### Given ###
+		_, err := NewImg("./img.go")
+		if err == nil {
+			t.Fatal("Load invalid file.")
+		}
+	})
+
+}

kadai1/sh-tatsuno/gophoto/dir/lookup.go

@@ -0,0 +1,36 @@
+package dir
+
+import (
+	"io/ioutil"
+	"path/filepath"
+)
+
+// Lookup lookup directory to find image files
+func Lookup(dir string, ext string, pathList []string) ([]string, error) {
+
+	fileInfos, err := ioutil.ReadDir(dir)
+	if err != nil {
+		return nil, err
+	}
+
+	for _, fileInfo := range fileInfos {
+
+		// get file info
+		path := filepath.Join(dir, fileInfo.Name())
+
+		// check if the path is about directory
+		if fileInfo.IsDir() {
+			pathList, err = Lookup(path, ext, pathList)
+			if err != nil {
+				return nil, err
+			}
+		}
+
+		// check if the postfix is equal to the input format
+		if filepath.Ext(path) == ext {
+			pathList = append(pathList, path)
+		}
+	}
+
+	return pathList, nil
+}

kadai1/sh-tatsuno/gophoto/dir/lookup_test.go

@@ -0,0 +1,73 @@
+package dir
+
+import (
+	"reflect"
+	"testing"
+)
+
+func Test_Lookup(t *testing.T) {
+
+	t.Run("OK: .jpg", func(t *testing.T) {
+		var actual []string
+		// ### Given ###
+		actual, err := Lookup("./test", ".jpg", actual)
+		if err != nil {
+			t.Fatalf("Failed test. err: %v", err)
+		}
+
+		expected := []string{"test/test1.jpg", "test/test3/test4.jpg", "test/test3/test5.jpg"}
+
+		// ### Then ###
+		if !reflect.DeepEqual(actual, expected) {
+			t.Fatalf("Failed test. expected: %v,\n but actual: %v", expected, actual)
+		}
+	})
+
+	t.Run("OK: .png", func(t *testing.T) {
+		var actual []string
+		// ### Given ###
+		actual, err := Lookup("./test", ".png", actual)
+		if err != nil {
+			t.Fatalf("Failed test. err: %v", err)
+		}
+
+		expected := []string{"test/test2.png", "test/test3/test6.png"}
+
+		// ### Then ###
+		if !reflect.DeepEqual(actual, expected) {
+			t.Fatalf("Failed test. expected: %v,\n but actual: %v", expected, actual)
+		}
+	})
+
+	t.Run("OK: .gif(empty)", func(t *testing.T) {
+		var actual []string
+		// ### Given ###
+		actual, err := Lookup("./test", ".gif", actual)
+		if err != nil {
+			t.Fatalf("Failed test. err: %v", err)
+		}
+
+		var expected []string
+
+		// ### Then ###
+		if !reflect.DeepEqual(actual, expected) {
+			t.Fatalf("Failed test. expected: %v,\n but actual: %v", expected, actual)
+		}
+	})
+
+	t.Run("NG: not found directory", func(t *testing.T) {
+		var actual []string
+		// ### Given ###
+		_, err := Lookup("./test2", ".jpg", actual)
+		if err == nil {
+			t.Fatalf("should be error.")
+		}
+
+		expected := "open ./test2: no such file or directory"
+
+		// ### Then ###
+		if err.Error() != expected {
+			t.Fatalf("Failed test. expected: %s,\n but actual: %s", expected, err.Error())
+		}
+	})
+}