为什么golang go-gin错误总是返回空object

Question

im trying to parse error validation in gin golang, but produce an empty object "{}"

Here is my 1st attempt:

resp, err := userService.UserRegistrationService(c)

if err != nil {
    c.JSON(http.StatusBadRequest, gin.H{"error": err})
    return
}

returning:

{
    "error": [
        {},
        {}
    ]
}

Here is my 2nd attempt:

resp, err := userService.UserRegistrationService(c)

if err != nil {
    dada := fmt.Errorf("%v", err)
    c.JSON(http.StatusBadRequest, dada)
    return
}

returning

{}

Take a look if I debug the err parameter:

resp, err := userService.UserRegistrationService(c)
    fmt.Println(err)
    if err != nil {
        dada := fmt.Errorf("%v", err)
        fmt.Println(dada)
        c.JSON(http.StatusBadRequest, dada)
        return
    }

Its return:

2020/11/10 12:41:46 stdout: Key: 'User.Email' Error:Field validation for 'Email' failed on the 'required' tag
2020/11/10 12:41:46 stdout: Key: 'User.Password' Error:Field validation for 'Password' failed on the 'required' tag

Can you guys help me, trying to search anywhere still no luck, I want return like this:

{
    "MyRequestStruct.PropertyOne": {
        "FieldNamespace": "MyRequestStruct.PropertyOne",
        "NameNamespace": "PropertyOne",
        "Field": "PropertyOne",
        "Name": "PropertyOne",
        "Tag": "required",
        "ActualTag": "required",
        "Kind": 24,
        "Type": {},
        "Param": "",
        "Value": ""
    },
    "MyRequestStruct.PropertyTwo": {
        "FieldNamespace": "MyRequestStruct.PropertyTwo",
        "NameNamespace": "PropertyTwo",
        "Field": "PropertyTwo",
        "Name": "PropertyTwo",
        "Tag": "required",
        "ActualTag": "required",
        "Kind": 24,
        "Type": {},
        "Param": "",
        "Value": ""
    }
}

Answer 1

You should try err.Error() instead of err while publishing as json response.

Try this :

resp, err := userService.UserRegistrationService(c)

if err != nil {
    c.JSON(http.StatusBadRequest, gin.H{"error": err.Error()})
    return
}

Answer 2

how to use it without an empty return?

resp, err := userService.UserRegistrationService(c)

if err != nil {
  c.JSON(http.StatusBadRequest, gin.H{
    "error": err.Error()
  })

  return

}