Initial backend repository commit.

Set up project files and add .gitignore to exclude local build/runtime artifacts. Made-with: Cursor
2026-03-09 21:28:58 +08:00
commit 4d8f2ec997
102 changed files with 25022 additions and 0 deletions
--- a/internal/service/upload_service.go
+++ b/internal/service/upload_service.go
@@ -0,0 +1,273 @@
+package service
+
+import (
+	"bytes"
+	"context"
+	"crypto/sha256"
+	"fmt"
+	"image"
+	"image/jpeg"
+	"image/png"
+	"io"
+	"mime"
+	"mime/multipart"
+	"net/http"
+	"path/filepath"
+	"strings"
+
+	"carrot_bbs/internal/pkg/s3"
+	_ "golang.org/x/image/bmp"
+	_ "golang.org/x/image/tiff"
+)
+
+// UploadService 上传服务
+type UploadService struct {
+	s3Client    *s3.Client
+	userService *UserService
+}
+
+// NewUploadService 创建上传服务
+func NewUploadService(s3Client *s3.Client, userService *UserService) *UploadService {
+	return &UploadService{
+		s3Client:    s3Client,
+		userService: userService,
+	}
+}
+
+// UploadImage 上传图片
+func (s *UploadService) UploadImage(ctx context.Context, file *multipart.FileHeader) (string, error) {
+	processedData, contentType, ext, err := prepareImageForUpload(file)
+	if err != nil {
+		return "", err
+	}
+
+	// 压缩后再计算哈希，确保同一压缩结果映射同一对象名
+	hash := sha256.Sum256(processedData)
+	hashStr := fmt.Sprintf("%x", hash)
+
+	objectName := fmt.Sprintf("images/%s%s", hashStr, ext)
+
+	url, err := s.s3Client.UploadData(ctx, objectName, processedData, contentType)
+	if err != nil {
+		return "", fmt.Errorf("failed to upload to S3: %w", err)
+	}
+
+	return url, nil
+}
+
+// getExtFromContentType 根据Content-Type获取文件扩展名
+func getExtFromContentType(contentType string) string {
+	baseType, _, err := mime.ParseMediaType(contentType)
+	if err == nil && baseType != "" {
+		contentType = baseType
+	}
+
+	switch contentType {
+	case "image/jpg", "image/jpeg":
+		return ".jpg"
+	case "image/png":
+		return ".png"
+	case "image/gif":
+		return ".gif"
+	case "image/webp":
+		return ".webp"
+	case "image/bmp", "image/x-ms-bmp":
+		return ".bmp"
+	case "image/tiff":
+		return ".tiff"
+	default:
+		return ""
+	}
+}
+
+// UploadAvatar 上传头像
+func (s *UploadService) UploadAvatar(ctx context.Context, userID string, file *multipart.FileHeader) (string, error) {
+	processedData, contentType, ext, err := prepareImageForUpload(file)
+	if err != nil {
+		return "", err
+	}
+
+	// 压缩后再计算哈希
+	hash := sha256.Sum256(processedData)
+	hashStr := fmt.Sprintf("%x", hash)
+
+	objectName := fmt.Sprintf("avatars/%s%s", hashStr, ext)
+
+	url, err := s.s3Client.UploadData(ctx, objectName, processedData, contentType)
+	if err != nil {
+		return "", fmt.Errorf("failed to upload to S3: %w", err)
+	}
+
+	// 更新用户头像
+	if s.userService != nil {
+		user, err := s.userService.GetUserByID(ctx, userID)
+		if err == nil && user != nil {
+			user.Avatar = url
+			err = s.userService.UpdateUser(ctx, user)
+			if err != nil {
+				// 更新失败不影响上传结果，只记录日志
+				fmt.Printf("[UploadAvatar] failed to update user avatar: %v\n", err)
+			}
+		}
+	}
+
+	return url, nil
+}
+
+// UploadCover 上传头图（个人主页封面）
+func (s *UploadService) UploadCover(ctx context.Context, userID string, file *multipart.FileHeader) (string, error) {
+	processedData, contentType, ext, err := prepareImageForUpload(file)
+	if err != nil {
+		return "", err
+	}
+
+	// 压缩后再计算哈希
+	hash := sha256.Sum256(processedData)
+	hashStr := fmt.Sprintf("%x", hash)
+
+	objectName := fmt.Sprintf("covers/%s%s", hashStr, ext)
+
+	url, err := s.s3Client.UploadData(ctx, objectName, processedData, contentType)
+	if err != nil {
+		return "", fmt.Errorf("failed to upload to S3: %w", err)
+	}
+
+	// 更新用户头图
+	if s.userService != nil {
+		user, err := s.userService.GetUserByID(ctx, userID)
+		if err == nil && user != nil {
+			user.CoverURL = url
+			err = s.userService.UpdateUser(ctx, user)
+			if err != nil {
+				// 更新失败不影响上传结果，只记录日志
+				fmt.Printf("[UploadCover] failed to update user cover: %v\n", err)
+			}
+		}
+	}
+
+	return url, nil
+}
+
+// GetURL 获取文件URL
+func (s *UploadService) GetURL(ctx context.Context, objectName string) (string, error) {
+	return s.s3Client.GetURL(ctx, objectName)
+}
+
+// Delete 删除文件
+func (s *UploadService) Delete(ctx context.Context, objectName string) error {
+	return s.s3Client.Delete(ctx, objectName)
+}
+
+func prepareImageForUpload(file *multipart.FileHeader) ([]byte, string, string, error) {
+	f, err := file.Open()
+	if err != nil {
+		return nil, "", "", fmt.Errorf("failed to open file: %w", err)
+	}
+	defer f.Close()
+
+	originalData, err := io.ReadAll(f)
+	if err != nil {
+		return nil, "", "", fmt.Errorf("failed to read file: %w", err)
+	}
+
+	// 优先从文件字节探测真实类型，避免前端压缩/转码后 header 与实际格式不一致
+	detectedType := normalizeImageContentType(http.DetectContentType(originalData))
+	headerType := normalizeImageContentType(file.Header.Get("Content-Type"))
+	contentType := detectedType
+	if contentType == "" || contentType == "application/octet-stream" {
+		contentType = headerType
+	}
+
+	compressedData, compressedType, err := compressImageData(originalData, contentType)
+	if err != nil {
+		// 压缩失败时回退到原图，保证上传可用性
+		compressedData = originalData
+		compressedType = contentType
+	}
+
+	if compressedType == "" {
+		compressedType = contentType
+	}
+	if compressedType == "" {
+		compressedType = http.DetectContentType(compressedData)
+	}
+
+	ext := getExtFromContentType(compressedType)
+	if ext == "" {
+		ext = strings.ToLower(filepath.Ext(file.Filename))
+	}
+	if ext == "" {
+		// 最终兜底，避免对象名无扩展名导致 URL 语义不明确
+		ext = ".jpg"
+	}
+
+	return compressedData, compressedType, ext, nil
+}
+
+func compressImageData(data []byte, contentType string) ([]byte, string, error) {
+	contentType = normalizeImageContentType(contentType)
+
+	// GIF/WebP 等格式先保留原图，避免动画和透明通道丢失
+	if contentType == "image/gif" || contentType == "image/webp" {
+		return data, contentType, nil
+	}
+
+	if contentType != "image/jpeg" &&
+		contentType != "image/png" &&
+		contentType != "image/bmp" &&
+		contentType != "image/x-ms-bmp" &&
+		contentType != "image/tiff" {
+		return data, contentType, nil
+	}
+
+	img, _, err := image.Decode(bytes.NewReader(data))
+	if err != nil {
+		return nil, "", fmt.Errorf("failed to decode image: %w", err)
+	}
+
+	var buf bytes.Buffer
+	switch contentType {
+	case "image/png":
+		encoder := png.Encoder{CompressionLevel: png.BestCompression}
+		if err := encoder.Encode(&buf, img); err != nil {
+			return nil, "", fmt.Errorf("failed to encode png: %w", err)
+		}
+		return buf.Bytes(), "image/png", nil
+	default:
+		// BMP/TIFF 等无损大图统一压缩为 JPEG，控制体积
+		if err := jpeg.Encode(&buf, img, &jpeg.Options{Quality: 82}); err != nil {
+			return nil, "", fmt.Errorf("failed to encode jpeg: %w", err)
+		}
+		return buf.Bytes(), "image/jpeg", nil
+	}
+}
+
+func normalizeImageContentType(contentType string) string {
+	if contentType == "" {
+		return ""
+	}
+
+	baseType, _, err := mime.ParseMediaType(contentType)
+	if err == nil && baseType != "" {
+		contentType = baseType
+	}
+
+	switch strings.ToLower(contentType) {
+	case "image/jpg":
+		return "image/jpeg"
+	case "image/jpeg":
+		return "image/jpeg"
+	case "image/png":
+		return "image/png"
+	case "image/gif":
+		return "image/gif"
+	case "image/webp":
+		return "image/webp"
+	case "image/bmp", "image/x-ms-bmp":
+		return "image/bmp"
+	case "image/tiff":
+		return "image/tiff"
+	default:
+		return contentType
+	}
+}