修复CopyObject实现，添加RealObjectKey实现真正零拷贝

internal/api/bucket_handler.go

@@ -237,7 +237,7 @@ func (h *S3Handler) handleCreateBucket(w http.ResponseWriter, r *http.Request, b
 		targetBucket := realBuckets[0]
 
 		// 创建虚拟存储桶到真实存储桶的映射
-		if err := h.storage.CreateVirtualBucketMapping(bucketName, "", targetBucket.Config.Name); err != nil {
+		if err := h.storage.CreateVirtualBucketMapping(bucketName, "", targetBucket.Config.Name, ""); err != nil {
 			h.sendS3Error(w, "InternalError", "Failed to create virtual bucket mapping", bucketName)
 			return
 		}

internal/api/multipart_handler.go

@@ -57,8 +57,8 @@ func (h *S3Handler) handleUploadPart(w http.ResponseWriter, r *http.Request) {
 				return
 			}
 
-			// 创建虚拟存储桶文件级映射
-			if err := h.storage.CreateVirtualBucketMapping(bucketName, key, targetBucket.Config.Name); err != nil {
+			// 创建虚拟存储桶文件级映射（对于Multipart，虚拟key和真实key相同）
+			if err := h.storage.CreateVirtualBucketMapping(bucketName, key, targetBucket.Config.Name, key); err != nil {
 				h.sendS3Error(w, "InternalError", "Failed to create virtual bucket file mapping", key)
 				return
 			}
@@ -204,8 +204,8 @@ func (h *S3Handler) handleMultipartUpload(w http.ResponseWriter, r *http.Request
 			return
 		}
 
-		// 创建虚拟存储桶文件级映射
-		if err := h.storage.CreateVirtualBucketMapping(bucketName, key, targetBucket.Config.Name); err != nil {
+		// 创建虚拟存储桶文件级映射（对于Multipart，虚拟key和真实key相同）
+		if err := h.storage.CreateVirtualBucketMapping(bucketName, key, targetBucket.Config.Name, key); err != nil {
 			h.sendS3Error(w, "InternalError", "Failed to create virtual bucket file mapping", key)
 			return
 		}

internal/api/object_handler.go

@@ -6,7 +6,9 @@ import (
 	"io"
 	"log"
 	"net/http"
+	"net/url"
 	"strconv"
+	"strings"
 	"time"
 
 	"github.com/DullJZ/s3-balance/internal/bucket"
@@ -56,6 +58,7 @@ func (h *S3Handler) handleGetObject(w http.ResponseWriter, r *http.Request, buck
 	var err error
 	var bucket1 *bucket.BucketInfo
 
+	var realKey string
 	if requestedBucket.IsVirtual() {
 		// 获取虚拟存储桶映射
 		mapping, err := h.storage.GetVirtualBucketMapping(bucketName, key)
@@ -64,21 +67,24 @@ func (h *S3Handler) handleGetObject(w http.ResponseWriter, r *http.Request, buck
 			return
 		}
 
-		// 获取映射到的真实存储桶
+		// 获取映射到的真实存储桶和真实key
 		bucket1, ok = h.bucketManager.GetBucket(mapping.RealBucketName)
 		if !ok {
 			h.sendS3Error(w, "InternalError", "Mapped real bucket not found", key)
 			return
 		}
 
+		realKey = mapping.RealObjectKey
 		h.recordBackendOperation(bucket1, bucket.OperationTypeB)
+	} else {
+		realKey = key
 	}
 
-	// 生成预签名下载URL
+	// 生成预签名下载URL（使用真实key）
 	downloadInfo, err := h.presigner.GenerateDownloadURL(
 		context.Background(),
 		bucket1,
-		key,
+		realKey,
 	)
 	if err != nil {
 		h.sendS3Error(w, "InternalError", "Failed to generate download URL", key)
@@ -182,6 +188,13 @@ func (h *S3Handler) handleHeadObject(w http.ResponseWriter, r *http.Request, buc
 
 // handlePutObject 上传对象
 func (h *S3Handler) handlePutObject(w http.ResponseWriter, r *http.Request, bucketName string, key string) {
+	// 检查是否是复制操作（CopyObject）
+	copySource := r.Header.Get("x-amz-copy-source")
+	if copySource != "" {
+		h.handleCopyObject(w, r, bucketName, key, copySource)
+		return
+	}
+
 	// 检查请求的存储桶是否为虚拟存储桶
 	requestedBucket, ok := h.bucketManager.GetBucket(bucketName)
 	if !ok {
@@ -211,8 +224,8 @@ func (h *S3Handler) handlePutObject(w http.ResponseWriter, r *http.Request, buck
 				return
 			}
 
-			// 创建虚拟存储桶文件级映射
-			if err := h.storage.CreateVirtualBucketMapping(bucketName, key, targetBucket.Config.Name); err != nil {
+			// 创建虚拟存储桶文件级映射（对于普通PUT，虚拟key和真实key相同）
+			if err := h.storage.CreateVirtualBucketMapping(bucketName, key, targetBucket.Config.Name, key); err != nil {
 				h.sendS3Error(w, "InternalError", "Failed to create virtual bucket file mapping", key)
 				return
 			}
@@ -290,6 +303,108 @@ func (h *S3Handler) handlePutObject(w http.ResponseWriter, r *http.Request, buck
 	}
 }
 
+// handleCopyObject 复制对象（只在数据库中创建新映射）
+func (h *S3Handler) handleCopyObject(w http.ResponseWriter, r *http.Request, destBucket, destKey, copySource string) {
+	// 解析复制源 (格式: /source-bucket/source-key 或 source-bucket/source-key)
+	copySource = strings.TrimPrefix(copySource, "/")
+	parts := strings.SplitN(copySource, "/", 2)
+	if len(parts) != 2 {
+		h.sendS3Error(w, "InvalidArgument", "Invalid copy source format", copySource)
+		return
+	}
+
+	sourceBucket := parts[0]
+	sourceKey := parts[1]
+
+	// URL 解码源对象键
+	sourceKey, err := url.QueryUnescape(sourceKey)
+	if err != nil {
+		h.sendS3Error(w, "InvalidArgument", "Invalid source key encoding", sourceKey)
+		return
+	}
+
+	// 检查目标存储桶是否存在
+	_, ok := h.bucketManager.GetBucket(destBucket)
+	if !ok {
+		h.sendS3Error(w, "NoSuchBucket", "The specified bucket does not exist", destBucket)
+		return
+	}
+
+	// 检查源存储桶是否存在
+	_, ok = h.bucketManager.GetBucket(sourceBucket)
+	if !ok {
+		h.sendS3Error(w, "NoSuchBucket", "The source bucket does not exist", sourceBucket)
+		return
+	}
+
+	// 获取元数据指令
+	metadataDirective := r.Header.Get("x-amz-metadata-directive")
+	var metadata map[string]string
+
+	if metadataDirective == "REPLACE" {
+		// 使用请求中的新元数据
+		metadata = make(map[string]string)
+		for k, v := range r.Header {
+			if strings.HasPrefix(strings.ToLower(k), "x-amz-meta-") {
+				metaKey := strings.TrimPrefix(strings.ToLower(k), "x-amz-meta-")
+				metadata[metaKey] = v[0]
+			}
+		}
+	}
+	// 如果是 COPY 或未指定，则复制源对象的元数据（在 storage.CopyObject 中处理）
+
+	// 获取源对象的映射信息
+	sourceMapping, err := h.storage.GetVirtualBucketMapping(sourceBucket, sourceKey)
+	if err != nil {
+		log.Printf("Failed to get source object mapping %s: %v", sourceKey, err)
+		h.sendS3Error(w, "NoSuchKey", "The specified key does not exist", sourceKey)
+		return
+	}
+
+	// 复制操作只创建新的虚拟映射，指向相同的真实对象（零拷贝）
+	destBucketInfo, destOk := h.bucketManager.GetBucket(destBucket)
+	if !destOk || !destBucketInfo.IsVirtual() {
+		h.sendS3Error(w, "NoSuchBucket", "The destination bucket does not exist", destBucket)
+		return
+	}
+
+	// 创建新的虚拟存储桶映射，指向相同的真实bucket和真实key
+	if err := h.storage.CreateVirtualBucketMapping(destBucket, destKey, sourceMapping.RealBucketName, sourceMapping.RealObjectKey); err != nil {
+		log.Printf("Failed to create virtual bucket mapping for copied object %s: %v", destKey, err)
+		h.sendS3Error(w, "InternalError", "Failed to create virtual bucket file mapping", destKey)
+		return
+	}
+
+	// 获取源对象信息用于响应
+	sourceObj, err := h.storage.GetObjectInfo(sourceMapping.RealObjectKey)
+	if err != nil {
+		log.Printf("Failed to get source object info: %v", err)
+	}
+
+	// 返回成功响应
+	w.Header().Set("Content-Type", "application/xml")
+
+	// 生成 ETag
+	etag := fmt.Sprintf("\"%x\"", time.Now().UnixNano())
+
+	// 构造 CopyObjectResult XML 响应
+	lastModified := time.Now().UTC().Format(time.RFC3339)
+	if sourceObj != nil {
+		lastModified = sourceObj.UpdatedAt.UTC().Format(time.RFC3339)
+	}
+
+	response := fmt.Sprintf(`<?xml version="1.0" encoding="UTF-8"?>
+<CopyObjectResult>
+	<LastModified>%s</LastModified>
+	<ETag>%s</ETag>
+</CopyObjectResult>`, lastModified, etag)
+
+	w.WriteHeader(http.StatusOK)
+	w.Write([]byte(response))
+
+	log.Printf("Object copied successfully: %s -> %s", sourceKey, destKey)
+}
+
 // handleDeleteObject 删除对象
 func (h *S3Handler) handleDeleteObject(w http.ResponseWriter, r *http.Request, bucketName string, key string) {
 	// 检查请求的存储桶是否为虚拟存储桶
@@ -301,6 +416,7 @@ func (h *S3Handler) handleDeleteObject(w http.ResponseWriter, r *http.Request, b
 
 	var targetBucket *bucket.BucketInfo
 	var err error
+	var realKey string
 
 	if requestedBucket.IsVirtual() {
 		// 获取虚拟存储桶文件映射
@@ -311,47 +427,59 @@ func (h *S3Handler) handleDeleteObject(w http.ResponseWriter, r *http.Request, b
 			return
 		}
 
-		// 获取映射到的真实存储桶
+		// 获取映射到的真实存储桶和真实key
 		targetBucket, ok = h.bucketManager.GetBucket(mapping.RealBucketName)
 		if !ok {
 			h.sendS3Error(w, "InternalError", "Mapped real bucket not found", key)
 			return
 		}
+
+		realKey = mapping.RealObjectKey
 	} else {
 		// 如果不是虚拟存储桶，拒绝客户端对真实存储桶的直接DELETE操作
 		w.WriteHeader(http.StatusNoContent)
 		return
 	}
 
-	h.recordBackendOperation(targetBucket, bucket.OperationTypeA)
-
-	// 生成预签名删除URL
-	deleteInfo, err := h.presigner.GenerateDeleteURL(
-		context.Background(),
-		targetBucket,
-		key,
-	)
-	if err != nil {
-		h.sendS3Error(w, "InternalError", "Failed to generate delete URL", key)
-		return
+	// 先删除虚拟存储桶映射
+	if err := h.storage.DeleteVirtualBucketObjectMapping(bucketName, key); err != nil {
+		log.Printf("Failed to delete virtual bucket mapping for %s/%s: %v", bucketName, key, err)
 	}
 
-	// 执行删除
-	req, _ := http.NewRequest("DELETE", deleteInfo.URL, nil)
-	client := &http.Client{Timeout: 30 * time.Second}
-	resp, err := client.Do(req)
+	// 检查是否还有其他映射指向同一个真实对象
+	count, err := h.storage.CountMappingsToRealObject(targetBucket.Config.Name, realKey)
 	if err != nil {
-		h.sendS3Error(w, "InternalError", "Failed to delete object", key)
-		return
+		log.Printf("Failed to count mappings for real object %s: %v", realKey, err)
 	}
-	defer resp.Body.Close()
 
-	// 从数据库中删除对象记录
-	h.storage.DeleteObject(key)
+	// 只有当没有其他映射引用时，才删除真实S3对象
+	if count == 0 {
+		h.recordBackendOperation(targetBucket, bucket.OperationTypeA)
 
-	// 如果是虚拟存储桶，还需要删除文件级别映射
-	if requestedBucket.IsVirtual() {
-		h.storage.DeleteVirtualBucketFileMapping(bucketName, key)
+		// 生成预签名删除URL（使用真实key）
+		deleteInfo, err := h.presigner.GenerateDeleteURL(
+			context.Background(),
+			targetBucket,
+			realKey,
+		)
+		if err != nil {
+			log.Printf("Failed to generate delete URL for %s: %v", realKey, err)
+		} else {
+			// 执行删除真实S3对象
+			req, _ := http.NewRequest("DELETE", deleteInfo.URL, nil)
+			client := &http.Client{Timeout: 30 * time.Second}
+			resp, err := client.Do(req)
+			if err != nil {
+				log.Printf("Failed to delete real S3 object %s: %v", realKey, err)
+			} else {
+				defer resp.Body.Close()
+			}
+		}
+
+		// 从数据库中删除对象记录
+		if err := h.storage.DeleteObject(realKey); err != nil {
+			log.Printf("Failed to delete object record for %s: %v", realKey, err)
+		}
 	}
 
 	// S3规范要求删除操作总是返回204

internal/storage/models.go

@@ -66,8 +66,9 @@ func (BucketMonthlyStats) TableName() string {
 type VirtualBucketMapping struct {
 	ID                uint      `gorm:"primaryKey" json:"id"`
 	VirtualBucketName string    `gorm:"index;size:255;not null" json:"virtual_bucket_name"`
-	ObjectKey         string    `gorm:"index;size:512;not null" json:"object_key"`
+	ObjectKey         string    `gorm:"index;size:512;not null" json:"object_key"`        // 虚拟对象key
 	RealBucketName    string    `gorm:"index;size:255;not null" json:"real_bucket_name"`
+	RealObjectKey     string    `gorm:"size:512;not null" json:"real_object_key"`          // 真实对象key
 	CreatedAt         time.Time `gorm:"not null" json:"created_at"`
 	UpdatedAt         time.Time `gorm:"not null" json:"updated_at"`
 }

internal/storage/service.go

@@ -101,6 +101,63 @@ func (s *Service) GetObjectInfo(key string) (*Object, error) {
 	return &obj, nil
 }
 
+// CopyObject 复制对象（只创建新的数据库映射记录，不复制实际数据）
+func (s *Service) CopyObject(sourceKey, destKey string, metadata map[string]string) error {
+	// 获取源对象信息
+	sourceObj, err := s.GetObjectInfo(sourceKey)
+	if err != nil {
+		return fmt.Errorf("source object not found: %w", err)
+	}
+
+	// 检查目标对象是否已存在
+	var existingObj Object
+	if err := s.db.Where("`key` = ?", destKey).Where("`deleted_at` IS NULL").First(&existingObj).Error; err == nil {
+		// 目标对象已存在，删除旧的
+		if err := s.DeleteObject(destKey); err != nil {
+			return fmt.Errorf("failed to delete existing destination object: %w", err)
+		}
+	}
+
+	// 清理已软删除的同名对象
+	var deletedObj Object
+	if err := s.db.Unscoped().Where("`key` = ?", destKey).Where("`deleted_at` IS NOT NULL").First(&deletedObj).Error; err == nil {
+		if err := s.db.Unscoped().Delete(&deletedObj).Error; err != nil {
+			return fmt.Errorf("failed to permanently delete soft-deleted object: %w", err)
+		}
+	}
+
+	// 创建新的对象记录，指向相同的真实存储桶
+	newObj := &Object{
+		Key:        destKey,
+		BucketName: sourceObj.BucketName, // 指向相同的真实桶
+		Size:       sourceObj.Size,
+	}
+
+	// 使用提供的元数据，如果没有则复制源对象的元数据
+	if len(metadata) > 0 {
+		newObj.Metadata = make(JSON)
+		for k, v := range metadata {
+			newObj.Metadata[k] = v
+		}
+	} else {
+		// 复制源对象的元数据
+		newObj.Metadata = make(JSON)
+		for k, v := range sourceObj.Metadata {
+			newObj.Metadata[k] = v
+		}
+	}
+
+	// 插入新记录
+	if err := s.db.Create(newObj).Error; err != nil {
+		return fmt.Errorf("failed to create copy object record: %w", err)
+	}
+
+	// 更新存储桶统计
+	s.updateBucketStats(sourceObj.BucketName)
+
+	return nil
+}
+
 // DeleteObject 删除对象记录（软删除）
 func (s *Service) DeleteObject(key string) error {
 	var obj Object
@@ -527,11 +584,12 @@ func (s *Service) GetAccessLogs(filter *AccessLogFilter) ([]*AccessLog, error) {
 }
 
 // CreateVirtualBucketMapping 创建虚拟存储桶文件级映射
-func (s *Service) CreateVirtualBucketMapping(virtualBucketName, objectKey, realBucketName string) error {
+func (s *Service) CreateVirtualBucketMapping(virtualBucketName, objectKey, realBucketName, realObjectKey string) error {
 	mapping := &VirtualBucketMapping{
 		VirtualBucketName: virtualBucketName,
 		ObjectKey:         objectKey,
 		RealBucketName:    realBucketName,
+		RealObjectKey:     realObjectKey,
 	}
 
 	if err := s.db.Create(mapping).Error; err != nil {
@@ -553,6 +611,17 @@ func (s *Service) GetVirtualBucketMapping(virtualBucketName, objectKey string) (
 	return &mapping, nil
 }
 
+// CountMappingsToRealObject 统计指向同一真实对象的映射数量
+func (s *Service) CountMappingsToRealObject(realBucketName, realObjectKey string) (int64, error) {
+	var count int64
+	if err := s.db.Model(&VirtualBucketMapping{}).
+		Where("real_bucket_name = ? AND real_object_key = ?", realBucketName, realObjectKey).
+		Count(&count).Error; err != nil {
+		return 0, fmt.Errorf("failed to count mappings: %w", err)
+	}
+	return count, nil
+}
+
 // GetVirtualBucketMappings 获取所有虚拟存储桶映射
 func (s *Service) GetVirtualBucketMappings() ([]*VirtualBucketMapping, error) {
 	var mappings []*VirtualBucketMapping
@@ -618,19 +687,45 @@ func (s *Service) GetVirtualBucketObjects(virtualBucketName string) ([]*Object,
 		return []*Object{}, nil
 	}
 
-	// 收集所有对象键
-	objectKeys := make([]string, 0, len(mappings))
+	// 收集所有真实对象键
+	realObjectKeys := make([]string, 0, len(mappings))
 	for _, mapping := range mappings {
-		objectKeys = append(objectKeys, mapping.ObjectKey)
+		realObjectKeys = append(realObjectKeys, mapping.RealObjectKey)
 	}
 
-	// 从对象表中查询这些对象
-	var objects []*Object
-	if err := s.db.Where("`key` IN ?", objectKeys).Find(&objects).Error; err != nil {
+	// 从对象表中查询这些真实对象
+	var realObjects []*Object
+	if err := s.db.Where("`key` IN ?", realObjectKeys).Find(&realObjects).Error; err != nil {
 		return nil, fmt.Errorf("failed to get objects for virtual bucket: %w", err)
 	}
 
-	return objects, nil
+	// 创建真实key到对象的映射
+	realObjectMap := make(map[string]*Object)
+	for _, obj := range realObjects {
+		realObjectMap[obj.Key] = obj
+	}
+
+	// 构建虚拟对象列表（使用虚拟key，但其他信息来自真实对象）
+	virtualObjects := make([]*Object, 0, len(mappings))
+	for _, mapping := range mappings {
+		if realObj, exists := realObjectMap[mapping.RealObjectKey]; exists {
+			// 创建虚拟对象副本，使用虚拟key
+			virtualObj := &Object{
+				ID:          realObj.ID,
+				Key:         mapping.ObjectKey, // 使用虚拟key
+				BucketName:  realObj.BucketName,
+				Size:        realObj.Size,
+				Metadata:    realObj.Metadata,
+				ContentType: realObj.ContentType,
+				ETag:        realObj.ETag,
+				CreatedAt:   realObj.CreatedAt,
+				UpdatedAt:   realObj.UpdatedAt,
+			}
+			virtualObjects = append(virtualObjects, virtualObj)
+		}
+	}
+
+	return virtualObjects, nil
 }
 
 // DeleteVirtualBucketFileMapping 删除虚拟存储桶文件映射