Unmarshalling a JSON that may or may not return an array?

Question

I\'m retrieving JSON from a third party website (home electricity usage), and depending on what I\'ve requested from the site, the JSON returned may or may not be an array.

Answer 1

You can try to make custom json unmarshal method, like

func (a *GwrcmCustom) UnmarshalJSON(b []byte) (err error) {
    g, ga := Gwrcmd{}, []Gwrcmd{}
    if err = json.Unmarshal(b, &g); err == nil {
        *a = make([]Gwrcmd, 1)
        []Gwrcmd(*a)[0] = Gwrcmd(g)
        return
    }
    if err = json.Unmarshal(b, &ga); err == nil {
        *a = GwrcmCustom(ga)
        return
    }
    return
}

GwrcmCustom is a custom type, slice of Gwrcm

type GwrcmCustom []Gwrcmd

So we will get slice always

Try this on Go playground

I hope this will help