Myujth

I have a struct which contains an other struct as value object.

type User struct 
 Name string `json:"name"``
 Email valueobject.Email `json:"email"`

The valueobject.Email looks like this:

type Email struct 
 value string

func (e *Email) Value() string 
 return e.Value

I want the value object as an immutable object, there is also a "factory" method in this is not necessary for my problem.

Now I want to return the User struct as json and therefor I use

response := map[string]interface"user": User
json.NewEncoder(w).Encode(response)

The result is:

 "user": 
 "name": "John Doe",
 "email": 
 "Email: "johndoe@example.com"
 
 

But I want something link this:

 "user": 
 "name": "John Doe",
 "email": "johndoe@example.com"
 

It sounds like you need valueobject.Email to implement the json.Marshaler interface:

func (e *Email) MarshalJSON() (byte, error) 
 return json.Marshal(e.Value())

That is the bare-minimum to implement what you are asking for. By implementing the json.Marshaler interface, it allows you to customize how json.Marshal renders your value.

Another option is to simplify Email into just a wrapper for string, instead of a struct:

type Email string

func (e Email) Value() string 
 return e

Since strings are already handled by json.Marshal, it should just work.

To make your Email type marshal the way you'd like, you'll need to make it implement the json.marshaler interface. GopherAcademy uses the following example:

func (d Dog) MarshalJSON() (byte, error) 
return json.Marshal(NewJSONDog(d))