kadai2-hisamura

Author: hisamura333

kadai2/convert/convert.go

@@ -0,0 +1,125 @@
+// Package convert is image conversion processing
+//
+// 画像変換処理。
+// 変換前と変換後の拡張子を指定し、画像変換を行います。
+// ディレクトリを選択し、再帰的にディレクトリ探索を行い変換します。
+// 変換前のファイルを削除したい場合は、remove(-r)フラグを指定します。
+package convert
+
+import (
+	"fmt"
+	"image"
+	"image/gif"
+	"image/jpeg"
+	"image/png"
+	"io/ioutil"
+	"os"
+	"path/filepath"
+	"strings"
+)
+
+// FlagOps is flag option
+type FlagOps struct {
+	Dir    string
+	Src    string
+	Dest   string
+	Remove bool
+}
+
+// FileDetails have Extionsion and FileName info
+type FileDetails struct {
+	Extension string
+	FileName  string
+}
+
+// Convert is image conversion processing
+func Convert(flagOps FlagOps) (string, error) {
+
+	files := dirwalk(flagOps.Dir)
+	var convertedName string
+
+	for _, file := range files {
+		fileDetails := FileDetails{
+			filepath.Ext(file),
+			filepath.Clean(file),
+		}
+
+		if strings.HasSuffix(fileDetails.Extension, flagOps.Src) {
+
+			decodeImg, err := decodeImage(fileDetails)
+			if err != nil {
+				return "", err
+			}
+
+			if flagOps.Remove {
+				defer os.Remove(fileDetails.FileName)
+			}
+
+			fileNameRemoveExt := strings.Replace(fileDetails.FileName, flagOps.Src, "", 1)
+			dstFile, err := os.Create(fmt.Sprintf(fileNameRemoveExt + flagOps.Dest))
+			if err != nil {
+				return "", err
+			}
+			convertedName = dstFile.Name()
+			defer dstFile.Close()
+
+			err = encodeImage(decodeImg, flagOps, dstFile)
+			if err != nil {
+				return "", err
+			}
+		}
+	}
+	return convertedName, nil
+
+}
+
+func decodeImage(fileDetails FileDetails) (image.Image, error) {
+	srcFile, err := os.Open(fileDetails.FileName)
+
+	defer srcFile.Close()
+
+	if err != nil {
+		return nil, err
+	}
+
+	decodeImg, _, err := image.Decode(srcFile)
+	return decodeImg, err
+}
+
+func encodeImage(decodeImg image.Image, flagOps FlagOps, dstFile *os.File) error {
+	switch flagOps.Dest {
+	case "jpeg", "jpg":
+		err := jpeg.Encode(dstFile, decodeImg, nil)
+		return err
+
+	case "gif":
+		err := gif.Encode(dstFile, decodeImg, nil)
+		return err
+
+	case "png":
+		err := png.Encode(dstFile, decodeImg)
+		return err
+
+	default:
+		return fmt.Errorf("Error: invalid extension")
+	}
+}
+
+//指定したディレクトリ配下のファイルを取得
+func dirwalk(dir string) []string {
+	files, err := ioutil.ReadDir(dir)
+	if err != nil {
+		panic(err)
+	}
+
+	var paths []string
+	for _, file := range files {
+		if file.IsDir() {
+			paths = append(paths, dirwalk(filepath.Join(dir, file.Name()))...)
+			continue
+		}
+		paths = append(paths, filepath.Join(dir, file.Name()))
+	}
+
+	return paths
+}

kadai2/convert/convert_test.go

@@ -0,0 +1,70 @@
+package convert
+
+import (
+	"testing"
+)
+
+type testImage struct {
+	name     string
+	src      string
+	dest     string
+	expected string
+}
+
+func TestSuccess(t *testing.T) {
+
+	cases := []testImage{
+		testImage{"jpgToGif", "jpg", "gif", "../testdata/test.gif"},
+		testImage{"jpgToGif", "jpg", "gif", "../testdata/test.gif"},
+		testImage{"jpgToPng", "jpg", "png", "../testdata/test.png"},
+		testImage{"gifToJpg", "gif", "jpg", "../testdata/test.jpg"},
+		testImage{"gifToPng", "gif", "png", "../testdata/test.png"},
+		testImage{"pngToGif", "png", "gif", "../testdata/test.gif"},
+		testImage{"pngToJpg", "gif", "png", "../testdata/test.png"},
+	}
+
+	for _, c := range cases {
+		t.Run(c.name, func(t *testing.T) {
+			testSuccessConvert(t, c)
+		})
+	}
+}
+
+func testSuccessConvert(t *testing.T, c testImage) {
+	t.Helper()
+	myflag := FlagOps{"../testdata", c.src, c.dest, false}
+	convertedNmae, err := Convert(myflag)
+
+	if convertedNmae != c.expected {
+		t.Fatal("differnt name")
+	}
+	if err != nil {
+		t.Fatal(err)
+	}
+}
+
+func TestFail(t *testing.T) {
+	cases := []testImage{
+		testImage{"jpgToGif", "jpg", "img", "../testdata/test.img"},
+	}
+
+	for _, c := range cases {
+		t.Run(c.name, func(t *testing.T) {
+			testFailConvert(t, c)
+		})
+	}
+
+}
+
+func testFailConvert(t *testing.T, c testImage) {
+	t.Helper()
+	myflag := FlagOps{"../testdata", c.src, c.dest, false}
+	convertedNmae, err := Convert(myflag)
+
+	if convertedNmae != "" {
+		t.Fatal("not empty name")
+	}
+	if err == nil {
+		t.Fatal("err nil")
+	}
+}

kadai2/go.mod

@@ -0,0 +1 @@
+module dojo6/kadai2

kadai2/kadai2

@@ -0,0 +1,44 @@
+package main
+
+import (
+	"dojo6/kadai2/convert"
+	"flag"
+	"fmt"
+)
+
+func main() {
+
+	var (
+		dir    = flag.String("dir", "./", "変換したいディレクトリ配下")
+		src    = flag.String("s", "png", "変換前の拡張子")
+		dest   = flag.String("d", "jpg", "変換後の拡張子")
+		remove = flag.Bool("r", false, "変換前の拡張子ファイルを削除するかのflag")
+	)
+
+	flag.Parse()
+
+	flagOps := convert.FlagOps{Dir: *dir, Src: *src, Dest: *dest, Remove: *remove}
+
+	fmt.Print(flagOps)
+
+	result := validation(flagOps)
+	if result {
+		fmt.Print("invalid extension")
+		return
+	}
+
+	convertFile, err := convert.Convert(flagOps)
+
+	if err != nil {
+		fmt.Println(err)
+	}
+
+	fmt.Printf("convert to %v", convertFile)
+}
+
+func validation(flagOps convert.FlagOps) bool {
+	if flagOps.Dest != "png" && flagOps.Dest != "jpg" && flagOps.Dest != "jpeg" && flagOps.Dest != "gif" {
+		return true
+	}
+	return false
+}