Implementing Scope inside Laravel

Merchant.php

<?php

namespace App\Model;

class Merchant extends Model
{
    //...
    
    /**
    * scope "productAvailable()" that can be use for Merchant instance
    * filter merchant has product available
    * @return Builder query
    */
    public function scopeProductAvailable($query)
    {
        return $query
        ->leftJoin('products', 'merchants.id', '=', 'products.merchant_id')
        ->where('products.availability', '1');
    }
  
    //...
}

MerchantController.php

<?php

namespace App\Http\Controllers\API\Customer;


class MerchantController extends Controller
{
     /*
     * Methods before implementing scopes
     */
      // public function index(MerchantRequest $request)
      // {
      //    $merchantList = Merchant::leftJoin('products', 'merchants.id', '=', 'products.merchant_id')
      //      ->where('products.availability', '1') 
      //      ->where(....
      //  }

      // public function searchActiveMerchant(MerchantRequest $request)
      // {
      //    $merchantList = Merchant::leftJoin('products', 'merchants.id', '=', 'products.merchant_id')
      //      ->where('products.availability', '1') 
      //      ->where(....
      //  }
  
  
     /*
     * Methods after implementing scopes
     */
    public function index(MerchantRequest $request)
    {
       $merchantList = Merchant::productAvailable()
       ->where(....
    }

    public function searchActiveMerchant(MerchantRequest $request)
    {
       $merchantList = Merchant::productAvailable()
       ->where(....
    }
  
}

scope is use to compiled repetitive query inside Model class, scope will return Query Builder instance.