In using Golang, we sometimes need to parse a JSON data without knowing or specifying a concrete type struct. We can do this by converting (json.Unmarshal) JSON data into an interface{}. We can then use it like a map. Accessing it like for example m["username"].(string)
func AddUserHandler(w http.ResponseWriter, r *http.Request) {
log.Println("Processing Register User")
var payload interface{} // The interface where we will save the converted JSON data.
buffer, err := ioutil.ReadAll(r.Body)
if err != nil {
log.Panic(err)
}
r.Body.Close() // Close this
json.Unmarshal(buffer, &payload) // Convert JSON data into interface{} type
m := payload.(map[string]interface{}) // To use the converted data we will need to convert it
// into a map[string]interface{}
validationErrors := make([]string, 0)
if len(strings.TrimSpace(m["username"].(string))) == 0 { // You can now access the data like this m["username"]
validationErrors = append(validationErrors, "Username is required")
}
if len(strings.TrimSpace(m["password"].(string))) == 0 {
validationErrors = append(validationErrors, "Password is required")
}
if len(strings.TrimSpace(m["name"].(string))) == 0 {
validationErrors = append(validationErrors, "Name is required")
}
if len(validationErrors) > 0 {
respondWithJSON(w, models.ResponsePayloadModel{
Total: 0,
Result: nil,
Errors: validationErrors,
})
}
// Your other codes goes here...
}