first commit

internal/services/upload.go

@@ -0,0 +1,92 @@
+package services
+
+import (
+	"errors"
+	"fmt"
+	"image"
+	"image/gif"
+	"image/jpeg"
+	"image/png"
+	"io"
+	"os"
+	"path"
+	"time"
+
+	nanoId "github.com/matoous/go-nanoid"
+)
+
+var (
+	// 文件最大数量
+	maxFileSize              = 10 << 20
+	ErrUnsupportedFileFormat = errors.New("文件格式不支持")
+	ErrFileStorePath         = errors.New("文件存储路径异常")
+	ErrFileGenerateName      = errors.New("文件名称生成异常")
+	ErrFileSaveFailed        = errors.New("文件保存失败")
+)
+
+func UploadFile(r io.Reader) (string, error) {
+	img, format, err := image.Decode(r)
+	if err != nil {
+		return "", fmt.Errorf("读取文件错误")
+	}
+	if errors.Is(err, image.ErrFormat) {
+		return "", ErrUnsupportedFileFormat
+	}
+	if format != "png" && format != "jpeg" && format != "gif" {
+		return "", ErrUnsupportedFileFormat
+	}
+
+	// 存放目录
+	dir := path.Join("upload", time.Now().Format(time.DateOnly))
+	exist, _ := pathExists(dir)
+	if !exist {
+		err := mkDir(dir)
+		if err != nil {
+			return "", ErrFileStorePath
+		}
+	}
+
+	filename, err := nanoId.Nanoid()
+	if err != nil {
+		return "", ErrFileGenerateName
+	}
+
+	filePath := path.Join("", dir, filename+"."+format)
+	f, err := os.Create(filePath)
+	if err != nil {
+		return "", ErrFileStorePath
+	}
+	defer func(f *os.File) {
+		_ = f.Close()
+	}(f)
+
+	var e error
+	switch format {
+	case "png":
+		e = png.Encode(f, img)
+	case "jpeg":
+		e = jpeg.Encode(f, img, nil)
+	case "gif":
+		e = gif.Encode(f, img, nil)
+	}
+	if e != nil {
+		return "", ErrFileSaveFailed
+	}
+
+	return "/" + filePath, nil
+}
+
+func pathExists(path string) (bool, error) {
+	_, err := os.Stat(path)
+	if err == nil {
+		return true, nil
+	}
+	if os.IsNotExist(err) {
+		return false, nil
+	}
+	return false, err
+}
+
+func mkDir(path string) error {
+	return os.MkdirAll(path, os.ModePerm)
+}