修改要编组为JSON的数据

Question

I have code where I am pulling out data from mongo & would like to give it out as an API response. My main challenge is not being able to transform data before pushing it out.

var result interface{}

respBody, err := json.Marshal(result)

Is it possible to edit marshalled result before it goes out? eg. Take out some fields?

Answer 1

A common way to accomplish what you described you're trying would be something like this:

type Data struct {
    Name    string
    Age     int
    Address *Address
    // more fields of your data object
}

type Response struct {
    Name string `json:"name"`
    Age  int    `json:"age"`
}

func GetResponse(d Data) ([]byte, error) {
    r := Response{
        Name: d.Name,
        Age:  d.Age,
        // anything else
    }

    return json.Marshal(r)
}