Laravel FormRequest Validation: if non-required field fails validation, change the value to null and continue

Question

I'm using Laravel 5.5 with FormRequest Validation. My current code is below. This is being used to validate the data form the request coming in.

If a nullable field fails validation in the request, I want the request to continue and make that field's value to NULL. So ,for example, if count is sent as a string instead of an integer.. I want to make the value of count NULL and continue with the request.

Is this possible using this FormRequest and if so, how?

<?php

namespace App\Http\Requests;

use Illuminate\Foundation\Http\FormRequest;
use Illuminate\Validation\Rule;
use Response;
use Illuminate\Contracts\Validation\Validator;
use Illuminate\Http\Exceptions\HttpResponseException;

class FieldsCheck extends FormRequest
{
    /**
     * Determine if the user is authorized to make this request.
     *
     * @return bool
     */
    public function authorize()
    {
        return true;
    }

    /**
     * Get the validation rules that apply to the request.
     *
     * @return array
     */
    public function rules()
    {
        return [
            'userid' => 'required|integer',
            'custom' => 'nullable|string|max:99',
            'count' => 'nullable|integer'

        ];
    }


    protected function failedValidation(Validator $validator)
    {
        // if it fails validation, is there a way to change the failing value to null here and continue with the request?
    }

}

kennyg kennyg · Accepted Answer · 2018-11-03T22:51:43

A couple of steps to do this.

Have an array ready of the fields for which you want to change the value.
Run a for each loop on the Validator to match the fields against the array you created in step 1.
If the validation fails and matches the array, use $this->merge([$key => null]) to overwrite the request value to null.
If validation fails and DOES NOT match the array, send back a validation error using the throw new HttpResponseException.

Here's some sample code below with comments:

protected function failedValidation(Validator $validator)
{
    $fields_to_null = ['count', 'custom']; // array of fields that should be changed to null if failed validation
    foreach($validator->errors()->getMessages() as $key => $msg) {
        // if fails validation && key exists in the array, change the field's value null and continue
        if (in_array($key, $fields_to_null)) {
            $this->merge([$key => null]);
        } else {
            // https://laracasts.com/discuss/channels/laravel/how-make-a-custom-formrequest-error-response-in-laravel-55?page=1
            // if an error does not match a field in the array, return validation error
            throw new HttpResponseException(response()->json($msg[0]),422); 
        }
    }
}

The request will continue on to the controller unless it hits that throw new httpResponseException

Laravel FormRequest Validation: if non-required field fails validation, change the value to null and continue

1 Answers