go-json-rest: JSON payload is empty - json

Question

I'm trying to use go-json-rest to create RESTful APIs
I have this model struct:
type Todo struct {
id int
name string
}
And I am trying to do a POST request to create an object of Todo type:
func CreateTodo(w rest.ResponseWriter, r *rest.Request) {
body, _ := ioutil.ReadAll(r.Body)
log.Println("body content is: ", string(body)) // here I can see {"name": "test1"}
var todo Todo = Todo{}
err := r.DecodeJsonPayload(&todo) // here the error shows JSON payload is empty
defer r.Body.Close()
if err != nil {
log.Println("error in parsing json")
rest.Error(w, err.Error(), http.StatusInternalServerError)
return
}
if todo.name == "" {
rest.Error(w, "todo name is required", 400)
return
}
lock.Lock()
var nextId int = len(todos)
// todos[nextId] = todo
todo.id = nextId // set its id
todos = append(todos, todo)
log.Println("num of todos: ", len(todos))
lock.Unlock()
w.WriteJson(&todo)
}
However, in the console of the POSTMAN client, the error shows:
{
"Error": "JSON payload is empty"
}
I was wondering where might go wrong. Thanks
Edit:
This should not be considered a duplicate question, because I am not even trying to use the json package to do marshalling/unmarshalling of JSON object. Instead I am using the rest.Request object (built in go-json-rest) to decode the json parameters as posted from client.
After much digging and search on this problem I found this answer below resolved my issue:
body, _ := ioutil.ReadAll(r.Body) will consume everything from the
request body. So after removing this line, the json parsing works!

Answer 1

I was just being silly doing body, _ := ioutil.ReadAll(r.Body) before decoding the JSON parameters without really understanding what ioutil.ReadAll() does to the request body.
As I quoted above in the edited post, ioutil.ReadAll() consumes everything in the request body, leaving nothing for the json decoder to parse. After removing the line body, _ := ioutil.ReadAll(r.Body), the json parsing works as expected.