问Laravel Api资源

EN

    { 
"data":[ 
    { 
        "first_name":"Rusty",
        "last_name":"Ferry",
        "specializations":{ 
            "specialization_id":11,
            "specialization_name":"Endocrinology"
        },
        "sub_specializations":null
    },
    { 
        "first_name":"Nadia",
        "last_name":"Ondricka",
        "specializations":{ 
            "specialization_id":22,
            "specialization_name":"ENT"
        },
        "sub_specializations":null
    },
    { 
        "first_name":"Erich",
        "last_name":"Torphy",
        "specializations":{ 
            "specialization_id":2,
            "specialization_name":"Cardiologist"
        },
        "sub_specializations":null
    }
    ]
}

    public function toArray($request)
{
    return [
        'first_name' => $this->first_name,
        'last_name'  => $this->last_name,
        'specializations' => new SpecializationsResource($this->specializations),
        'sub_specializations' => new SubSpecializationsResource($this->sub_specializations),
    ];
}

    public function toArray($request)
{
    return [
        'specialization_id' => $this->specialization_id,
        'specialization_name' => $this->specialization_name,
    ];

}

    public function toArray($request)
{
    return [
        'sub_specialization_id' => $this->sub_specialization_id,
        'sub_specialization_name' => $this->sub_specialization_name,
        'doctors' => new DoctorsResource($this->doctors),
    ];
}

    protected $user;

public function __construct(Doctors $doctors){
    $this->doctors = $doctors;
}

public function index()
{
    $doctors = $this->doctors->with('specializations', 'subSpecializations')->get();
    return DoctorsResource::collection($doctors);
}

{ 
"data":[ 
    { 
        "first_name":"Rusty",
        "last_name":"Ferry",
        "specializations":{ 
            "specialization_id":11,
            "specialization_name":"Endocrinology"
        },
        "sub_specializations": {
            "sub_specialization_name":"value"
       }
    }
  ]
}