Laravel 查询附近的数据

<?php

namespace App\Models;

use Illuminate\Database\Eloquent\Model;

class School extends Model
{
    protected $table = 'school';

    public function getDistanceAttribute($value)
    {
        $value = sprintf('%.2f', $value);
        return $value > 1 ? $value . 'km' : ($value * 1000) . 'm';
    }
}

<?php

namespace App\Http\Controllers;

use App\Models\School;
use Illuminate\Support\Facades\Validator;
use Illuminate\Http\Request;

class SearchController extends Controller
{
    public function index(Request $request)
    {
        $input = $request->only(['lat', 'lng']);

        $validator = Validator::make($input, [
            'lat' => [
                'required',
                'regex:/^[\-\+]?(0?\d{1,2}\.\d{1,6}|1[0-7]?\d{1}\.\d{1,6}|180\.0{1,6})$/'
            ],
            'lng' => [
                'required',
                'regex:/^[\-\+]?([0-8]?\d{1}\.\d{1,6}|90\.0{1,6})$/'
            ],
        ]);

        // $validator->setAttributeNames([
        //     'lat'   => '经度',
        //     'lng'   => '纬度',
        // ]);

        if($validator->fails()) {
            return $validator->errors()->first();
        }

        // 附近 n 公里
        $distance = $request->query('distance', 5);

        $data = School::select('*')
                    ->selectRaw('( 6371 * acos( cos( radians(' . $input['lat'] . ') ) * cos( radians( lat ) ) * cos( radians( lng ) - radians(' . $input['lng'] . ') ) + sin( radians(' . $input['lat'] .') ) * sin( radians(lat) ) ) ) AS distance')
                    ->havingRaw('distance < ' . $distance)
                    ->orderBy('distance')
                    ->get();

        return  response()->json([
                    'data' => $data,
                ]);
    }
}

Route::get('/', 'SearchController@index');