Return single object instead array for exactly one relation between node

Users Dgraph
2

I’m ended using custom json unmarshal function like this (in golang)

package main

import (
	"encoding/json"
	"fmt"
)

type School struct {
	Name   string `json:"name"`
	Adress string `json:"address"`
}

type Student struct {
	Name   string `json:"name"`
	School School `json:"school"`
}

func (s *Student) UnmarshalJSON(data []byte) error {
	type TempStudent Student
	temp := &struct {
		*TempStudent
		Schools []School `json:"study_at"`
	}{TempStudent: (*TempStudent)(s)}
	if err := json.Unmarshal(data, &temp); err != nil {
		return err
	}
	if len(temp.Schools) == 1 {
		s.School = temp.Schools[0]
	}
	return nil
}

func main() {
	data := `{"name": "Crazy Student", "study_at": [{"name": "XYZ highschool", "address": "a school adresss"}]}`
	var s Student
	err := json.Unmarshal([]byte(data), &s)
	if err != nil {
		fmt.Println(err.Error())
	}
	fmt.Println(s.School.Name)  //no more s.School[0].Name
}

but I still wishing built-in tag/filter in dgraph to return single object instead array for special case, maybe something like this:

{
   query(func: eq(studentID, "001")) {
     name
     study_at @singleObject {    # tag/filter to tell dgraph to return single object, instead array of object
        name
        address  
   }
}