同步支持动态更新取件码长度，调整存量取件码以适配新长度并优化相关逻辑和文档。

docs/config_specification.md

@@ -17,7 +17,7 @@
 | 字段名 | 类型 | 含义 | 示例 |
 | :--- | :--- | :--- | :--- |
 | `admin_password_hash` | string | 管理员密码的 bcrypt 哈希值 | `$2a$10$...` |
-| `pickup_code_length` | int | 自动生成的取件码长度（已包含在公共配置接口中） | `6` |
+| `pickup_code_length` | int | 自动生成的取件码长度。变更后系统将自动对存量取件码进行右侧补零或截取以适配新长度。 | `6` |
 | `pickup_fail_limit` | int | 单个 IP 对单个取件码尝试失败的最大次数，超过后将被临时封禁 | `5` |
 | `jwt_secret` | string | 用于签发管理端 JWT Token 的密钥，建议设置为复杂随机字符串 | `file-relay-secret` |
 

docs/docs.go

@@ -1077,7 +1077,7 @@ const docTemplate = `{
                     "type": "string"
                 },
                 "pickup_code_length": {
-                    "description": "取件码长度",
+                    "description": "取件码长度 (变更后将自动通过右侧补零或截取调整存量数据)",
                     "type": "integer"
                 },
                 "pickup_fail_limit": {

docs/swagger.json

@@ -1070,7 +1070,7 @@
                     "type": "string"
                 },
                 "pickup_code_length": {
-                    "description": "取件码长度",
+                    "description": "取件码长度 (变更后将自动通过右侧补零或截取调整存量数据)",
                     "type": "integer"
                 },
                 "pickup_fail_limit": {

docs/swagger.yaml

@@ -113,7 +113,7 @@ definitions:
         description: JWT 签名密钥
         type: string
       pickup_code_length:
-        description: 取件码长度
+        description: 取件码长度 (变更后将自动通过右侧补零或截取调整存量数据)
         type: integer
       pickup_fail_limit:
         description: 取件失败尝试限制

internal/api/admin/config.go

@@ -4,6 +4,7 @@ import (
 	"FileRelay/internal/bootstrap"
 	"FileRelay/internal/config"
 	"FileRelay/internal/model"
+	"FileRelay/internal/service"
 	"net/http"
 
 	"github.com/gin-gonic/gin"
@@ -51,9 +52,21 @@ func (h *ConfigHandler) UpdateConfig(c *gin.Context) {
 		newConfig.Database.Path = config.GlobalConfig.Database.Path
 	}
 
+	// 检查取件码长度是否变化
+	pickupCodeLengthChanged := newConfig.Security.PickupCodeLength != config.GlobalConfig.Security.PickupCodeLength && newConfig.Security.PickupCodeLength > 0
+
 	// 更新内存配置
 	config.UpdateGlobalConfig(&newConfig)
 
+	// 如果长度变化，同步更新现有取件码
+	if pickupCodeLengthChanged {
+		batchService := service.NewBatchService()
+		if err := batchService.UpdateAllPickupCodes(newConfig.Security.PickupCodeLength); err != nil {
+			c.JSON(http.StatusInternalServerError, model.ErrorResponse(model.CodeInternalError, "Failed to update existing pickup codes: "+err.Error()))
+			return
+		}
+	}
+
 	// 重新初始化存储（热更新业务逻辑）
 	if err := bootstrap.ReloadStorage(); err != nil {
 		c.JSON(http.StatusInternalServerError, model.ErrorResponse(model.CodeInternalError, "Failed to reload storage: "+err.Error()))

internal/config/config.go

@@ -24,7 +24,7 @@ type SiteConfig struct {
 
 type SecurityConfig struct {
 	AdminPasswordHash string `yaml:"admin_password_hash" json:"admin_password_hash"` // 管理员密码哈希 (bcrypt)
-	PickupCodeLength  int    `yaml:"pickup_code_length" json:"pickup_code_length"`   // 取件码长度
+	PickupCodeLength  int    `yaml:"pickup_code_length" json:"pickup_code_length"`   // 取件码长度 (变更后将自动通过右侧补零或截取调整存量数据)
 	PickupFailLimit   int    `yaml:"pickup_fail_limit" json:"pickup_fail_limit"`     // 取件失败尝试限制
 	JWTSecret         string `yaml:"jwt_secret" json:"jwt_secret"`                   // JWT 签名密钥
 }

internal/service/batch_service.go

@@ -6,8 +6,12 @@ import (
 	"FileRelay/internal/storage"
 	"context"
 	"errors"
+	"math/big"
+	"strings"
 	"time"
 
+	"crypto/rand"
+
 	"gorm.io/gorm"
 )
 
@@ -84,3 +88,85 @@ func (s *BatchService) IncrementDownloadCount(batchID string) error {
 	return s.db.Model(&model.FileBatch{}).Where("id = ?", batchID).
 		UpdateColumn("download_count", gorm.Expr("download_count + ?", 1)).Error
 }
+
+func (s *BatchService) GeneratePickupCode(length int) (string, error) {
+	const charset = "0123456789"
+	b := make([]byte, length)
+	for i := range b {
+		num, err := rand.Int(rand.Reader, big.NewInt(int64(len(charset))))
+		if err != nil {
+			return "", err
+		}
+		b[i] = charset[num.Int64()]
+	}
+	// 检查是否冲突 (排除已删除的，但包括活跃的和已过期的)
+	var count int64
+	s.db.Model(&model.FileBatch{}).Where("pickup_code = ?", string(b)).Count(&count)
+	if count > 0 {
+		return s.GeneratePickupCode(length) // 递归生成
+	}
+	return string(b), nil
+}
+
+func (s *BatchService) UpdateAllPickupCodes(newLength int) error {
+	var batches []model.FileBatch
+	// 只更新未删除的记录，包括 active 和 expired
+	if err := s.db.Find(&batches).Error; err != nil {
+		return err
+	}
+
+	return s.db.Transaction(func(tx *gorm.DB) error {
+		for _, batch := range batches {
+			oldCode := batch.PickupCode
+			if len(oldCode) == newLength {
+				continue
+			}
+
+			var newCode string
+			if len(oldCode) < newLength {
+				// 右侧补零，方便用户输入原码后通过补 0 完成输入
+				newCode = oldCode + strings.Repeat("0", newLength-len(oldCode))
+			} else {
+				// 截取前 newLength 位，保留原码头部
+				newCode = oldCode[:newLength]
+			}
+
+			// 检查冲突 (在事务中检查)
+			var count int64
+			tx.Model(&model.FileBatch{}).Where("pickup_code = ? AND id != ?", newCode, batch.ID).Count(&count)
+			if count > 0 {
+				// 如果冲突，生成一个新的随机码
+				var err error
+				newCode, err = s.generateUniquePickupCodeInTx(tx, newLength)
+				if err != nil {
+					return err
+				}
+			}
+
+			if err := tx.Model(&batch).Update("pickup_code", newCode).Error; err != nil {
+				return err
+			}
+		}
+		return nil
+	})
+}
+
+func (s *BatchService) generateUniquePickupCodeInTx(tx *gorm.DB, length int) (string, error) {
+	const charset = "0123456789"
+	for {
+		b := make([]byte, length)
+		for i := range b {
+			num, err := rand.Int(rand.Reader, big.NewInt(int64(len(charset))))
+			if err != nil {
+				return "", err
+			}
+			b[i] = charset[num.Int64()]
+		}
+
+		var count int64
+		tx.Model(&model.FileBatch{}).Where("pickup_code = ?", string(b)).Count(&count)
+		if count == 0 {
+			return string(b), nil
+		}
+	}
+}

internal/service/upload_service.go

@@ -6,9 +6,7 @@ import (
 	"FileRelay/internal/model"
 	"FileRelay/internal/storage"
 	"context"
-	"crypto/rand"
 	"fmt"
-	"math/big"
 	"mime/multipart"
 	"path/filepath"
 	"time"
@@ -27,7 +25,8 @@ func NewUploadService() *UploadService {
 
 func (s *UploadService) CreateBatch(ctx context.Context, files []*multipart.FileHeader, remark string, expireType string, expireValue interface{}) (*model.FileBatch, error) {
 	// 1. 生成取件码
-	pickupCode, err := s.generatePickupCode(config.GlobalConfig.Security.PickupCodeLength)
+	batchService := NewBatchService()
+	pickupCode, err := batchService.GeneratePickupCode(config.GlobalConfig.Security.PickupCodeLength)
 	if err != nil {
 		return nil, err
 	}
@@ -63,7 +62,8 @@ func (s *UploadService) CreateBatch(ctx context.Context, files []*multipart.File
 
 func (s *UploadService) CreateTextBatch(ctx context.Context, content string, remark string, expireType string, expireValue interface{}) (*model.FileBatch, error) {
 	// 1. 生成取件码
-	pickupCode, err := s.generatePickupCode(config.GlobalConfig.Security.PickupCodeLength)
+	batchService := NewBatchService()
+	pickupCode, err := batchService.GeneratePickupCode(config.GlobalConfig.Security.PickupCodeLength)
 	if err != nil {
 		return nil, err
 	}
@@ -136,22 +136,3 @@ func (s *UploadService) processFile(ctx context.Context, tx *gorm.DB, batchID st
 
 	return item, nil
 }
-
-func (s *UploadService) generatePickupCode(length int) (string, error) {
-	const charset = "0123456789"
-	b := make([]byte, length)
-	for i := range b {
-		num, err := rand.Int(rand.Reader, big.NewInt(int64(len(charset))))
-		if err != nil {
-			return "", err
-		}
-		b[i] = charset[num.Int64()]
-	}
-	// 检查是否冲突
-	var count int64
-	s.db.Model(&model.FileBatch{}).Where("pickup_code = ? AND status = ?", string(b), "active").Count(&count)
-	if count > 0 {
-		return s.generatePickupCode(length) // 递归生成
-	}
-	return string(b), nil
-}