Validate Parameters as a JSON String in Laravel

Question

Front End Part

The parameters are being sent like this:

Laravel Request

class CarCreateRequest extends FormRequest
{
    /**
     * Determine if the user is authorized to make this request.
     *
     * @return bool
     */
    public function authorize()
    {
        //TODO: Define authorization logic, possibly a middleware
        return true;
    }  

    /**
     * Get the validation rules that apply to the request.
     *
     * @return array
     */
    public function rules()
    {
        return [
            'car.name' => 'present|required'
        ];
    }
}

Real Problem

The request class always validates to false. I checked the Validating Array section, but it looks like this works sending parameters like this:

car[name]=Spidey Mobile

However, I need to send this data stringified using JSON.stringify().

Is there a workaround for this? It looks like dot notation isn't working since this is a JSON string rather than an array. I've tried modifying the request data before being evaluated, but I haven't found anything that works for Laravel 5.7.

Answer 1

Here's the solution, I used both the sanitize and validator method within the request in order to change the request data before being evaluated.

class CarCreateRequest extends FormRequest
{
    /**
    * Determine if the user is authorized to make this request.
    *
    * @return bool
    */
    public function authorize()
    {
        //TODO: Define authorization logic, possibly a middleware
        return true;
    }  

    public function validator($factory)
    {
    return $factory->make(
        $this->sanitize(), $this->container->call([$this, 'rules']), $this->messages()
    );
    }

    public function sanitize()
    {
        $this->merge([
            'car' => json_decode($this->input('car'), true)
        ]);
        return $this->all();
    }

    /**
    * Get the validation rules that apply to the request.
    *
    * @return array
    */
    public function rules()
    {
        return [
            'car.name' => 'present|required'
        ];
    }
}

The json_decode will transform the JSON string into an array that can be validated by Laravel.