标准库的errors包不能完全满足我们的业务需求，通常我们需要自己创建一个错误包

1. 自定义error类型

Go中自定义error是非常简单的，实现Error() string接口即可

  1. package errcode
  3. type Error struct {
  4.     Code int `json:"code"`
  5.     Msg string `json:"msg"`
  6.     Details []string `json:"details"`
  7. }
  9. func (e *Error) Error() string {
  10.     return fmt.Sprintf("错误码：%d 错误信息：%s \n", e.Code, e.Msg)
  11. }

2. 新增创建Error的方法

  1. var codes = make(map[int]string)
  3. func NewError(code int, msg string) *Error {
  4.     if _, ok := codes[code]; !ok {
  5.         panic(fmt.Sprintf("错误码%d已存在，请更换一个", code))
  6.     }
  7.     codes[code] = msg
  8.     return &Error{
  9.         Code: code,
  10.         Msg: msg,
  11.     }
  12. }
  14. // 在原错误上创建一个带有更过细节信息的错误
  15. func (e *Error) WithDetails(details ...string) *Error {
  16.     newError := *e
  17.     newError.Details = make([]string, 0)
  18.     for _, d := range details {
  19.         newError.Details = append(newError.Details, d)
  20.     }
  21.     reutrn &newError
  22. }

3. 自定义常用错误

  1. var (
  2.     Success                   = NewError(0, "成功")
  3.     ServerError               = NewError(10000000, "服务内部错误")
  4.     InvalidParams             = NewError(10000001, "入参错误")
  5.     NotFound                  = NewError(10000002, "找不到")
  6.     UnauthorizedAuthNotExist  = NewError(10000003, "鉴权失败，找不到对应的用户")
  7.     UnauthorizedTokenError    = NewError(10000004, "鉴权失败，token错误")
  8.     UnauthorizedTokenTimeout  = NewError(10000005, "鉴权失败，token超时")
  9.     UnauthorizedTokenGenerate = NewError(10000006, "鉴权失败，token生成失败")
  10.     TooManyRequests           = NewError(10000007, "请求过多")
  11.     IdempotenceTokenError     = NewError(10000008, "幂等性token错误")
  12. )

4. 新增错误码转响应码方法

  1. func (e *Error) StatusCode() int {
  2.     switch e.Code {
  3.         case Success.Code:
  4.             return http.StatusOK
  5.         case ServerError.Code:
  6.             return http.StatusInternalServerError
  7.         case InvalidParams.Code:
  8.             return http.StatusBadRequest
  9.         case NotFound.Code:
  10.             return http.StatusNotFound
  11.         case UnauthorizedAuthNotExist.Code:
  12.             fallthrough
  13.         case UnauthorizedTokenError.Code:
  14.             fallthrough
  15.         case UnauthorizedTokenTimeout.Code:
  16.             fallthrough
  17.         case UnauthorizedTokenGenerate.Code:
  18.             return http.StatusUnauthorized
  19.         case TooManyRequests.Code:
  20.             return http.StatusTooManyRequest
  21.     }
  23.     return http.StatusInternalServerError
  24. }

5. 总结

  • 自定义错误类型直接实现error接口即可
  • 自定义常用错误方便使用
  • 自定义创建错误方便携带更过细节信息