shipping-portal/app/Http/Resources/ContainerResource.php

<?php

namespace App\Http\Resources;

use Illuminate\Http\Resources\Json\JsonResource;

class ContainerResource extends JsonResource
{
    /**
     * Transform the resource into an array.
     *
     * @param  \Illuminate\Http\Request  $request
     * @return array
     */
    public function toArray($request)
    {
        return [
            'id' => $this->id,
            'container_reference' => $this->reference,
            'container_type' => $this->container_type,
            'container_number' => $this->container_number,
            'seal_reference' => $this->seal_reference,
            'transport' => TransportResource::collection($this->transports),
        ];
    }
}