签名

sdk/sign.go

@@ -9,57 +9,68 @@ import (
 	"sync"
 )
 
-// Order represents an order object used for signing parameters
+// Order 表示订单对象，用于签名参数
 type Order struct {
-	Uid         string
-	BsTradeNo   string
-	Role        string
-	RoleId      string
-	ServerId    string
-	GoodsName   string
-	OutTradeNo  string
-	Body        string
-	CpExtraInfo string
-	TradeState  string
-	TotalFee    string
-	PayFee      string
-	PayTime     string
+	Uid         string // 用户ID
+	BsTradeNo   string // 交易编号
+	Role        string // 用户角色
+	RoleId      string // 角色ID
+	ServerId    string // 服务器ID
+	GoodsName   string // 商品名称
+	OutTradeNo  string // 外部交易编号
+	Body        string // 商品描述
+	CpExtraInfo string // 扩展信息
+	TradeState  string // 交易状态
+	TotalFee    string // 总费用
+	PayFee      string // 支付费用
+	PayTime     string // 支付时间
 }
 
-// Config holds the configuration for SDK, such as appId and secret keys
+// Config 用于保存SDK的配置信息，例如appId和secretKey
 type Config struct {
-	SecretKey string
+	SecretKey string // 秘钥
 }
 
-// SDK struct encapsulates SDK configuration and utility functions
+// SDK结构体封装了SDK的配置和工具函数
 type SDK struct {
-	SecretKey string
+	SecretKey string // 秘钥
 }
 
-// Singleton instance and mutex for thread safety
+// 单例实例和互斥锁，确保线程安全
 var instance *SDK
-var once2 sync.Once
+var onces sync.Once
 
-// New initializes a new SDK with the given configuration, but ensures that only one instance exists.
+// New 返回一个SDK单例实例，初始化时传入秘钥
 func New(secretKey string) *SDK {
-	once2.Do(func() {
+	onces.Do(func() {
 		instance = &SDK{
 			SecretKey: secretKey,
 		}
 	})
-	return instance
+	return instance // 返回单例实例
 }
 
-// Md5String generates MD5 hash of a given string
+// Md5String 生成给定字符串的MD5哈希值并返回十六进制字符串
 func (s *SDK) Md5String(str string) string {
-	hash := md5.Sum([]byte(str)) // Use md5.Sum for fixed size output
-	return hex.EncodeToString(hash[:])
+	hash := md5.Sum([]byte(str))       // 计算MD5哈希
+	return hex.EncodeToString(hash[:]) // 转为十六进制字符串并返回
 }
 
-// SignParam generates a signed URL-encoded string for the provided Order object
+// SignParam 为提供的Order对象生成签名
 func (s *SDK) SignParam(order *Order) (string, error) {
-	// Create a map of the parameters to be signed
-	paramMap := map[string]string{
+	// 创建待签名参数映射
+	paramMap := s.createParamMap(order)
+
+	// 按照字典顺序排序并生成待签名字符串
+	signStr := s.buildSignString(paramMap)
+
+	// 计算最终签名并返回
+	return s.Md5String(signStr), nil
+}
+
+// createParamMap 构建参数映射，跳过 "sign" 和 "-" 键
+func (s *SDK) createParamMap(order *Order) map[string]string {
+	return map[string]string{
 		"uid":          order.Uid,
 		"bs_trade_no":  order.BsTradeNo,
 		"role":         order.Role,
@@ -73,43 +84,46 @@ func (s *SDK) SignParam(order *Order) (string, error) {
 		"total_fee":    order.TotalFee,
 		"pay_fee":      order.PayFee,
 		"pay_time":     order.PayTime,
-		"sign":         "",
+		"sign":         "", // 初始化签名为空
 	}
-
-	// Generate the signed value
-	signStr := s.SortMapString(paramMap) + s.SecretKey
-
-	// Return the MD5 hash
-	return s.Md5String(signStr), nil
 }
 
-// SortMapString sorts the keys of a map and returns a concatenated string
-func (s *SDK) SortMapString(params map[string]string) string {
+// buildSignString 按照字典顺序排序参数并拼接成签名字符串
+func (s *SDK) buildSignString(params map[string]string) string {
 	var builder strings.Builder
-	keys := make([]string, 0, len(params))
+	keys := s.getSortedKeys(params) // 获取排序后的键
+
+	// 拼接所有键对应的值
+	for _, k := range keys {
+		builder.WriteString(params[k])
+	}
+
+	// 将秘钥追加到签名字符串后
+	builder.WriteString(s.SecretKey)
+
+	return builder.String()
+}
 
-	// Avoid sorting the "sign" and "-" keys
+// getSortedKeys 返回排除 "sign" 和 "-" 键后的排序键列表
+func (s *SDK) getSortedKeys(params map[string]string) []string {
+	var keys []string
 	for k := range params {
+		// 跳过 "sign" 和 "-" 键
 		if k == "sign" || k == "-" {
 			continue
 		}
 		keys = append(keys, k)
 	}
-	sort.Strings(keys) // Sort the keys
-
-	// Efficiently concatenate the values
-	for _, k := range keys {
-		builder.WriteString(params[k])
-	}
-
-	return builder.String()
+	sort.Strings(keys) // 排序键
+	return keys
 }
 
-// ToJson converts an interface{} to JSON string
+// ToJson 将一个接口类型转换为JSON字符串
 func (s *SDK) ToJson(item interface{}) (string, error) {
+	// 使用json.Marshal将对象转换为JSON
 	res, err := json.Marshal(item)
 	if err != nil {
-		return "", err // Simplified error handling
+		return "", err // 返回错误
 	}
-	return string(res), nil
+	return string(res), nil // 返回JSON字符串
 }