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Mayur Pande
Mayur Pande
Courses Plus Student 11,711 Points

Undefined index error

I am using slim-3 to build an authentication system. However at the moment I am struggling to get the errors to display on the sign-up page;

It keeps giving me the error

Undefined index: errors in /var/www/html/tobylindsell.com/app/Middleware/ValidationErrorsMiddleware.php on line 23, referer: http://tobylindsell.com/admin

However when I run a var_dump($_SESSION['errors'] on my Validator file it shows all the errors. Only when passed to my ValidationErrorsMiddleware.php file it doesn't show up.

Originally I was getting the error;

Undefined: _SESSION variable

But then I put a session_start at the top of my ValidationErrorsMiddleware.php this got rid of this error but not the

Undefined index: errors

Here is my ValidationErrorsMiddlesware.php


namespace App\Middleware;

use App\Validation\Validator;
//inherits base middleware
class ValidationErrorsMiddleware extends Middleware{

    public function __invoke($request,$response,$next){

        //we unset the session as we no longer need it

        //after state has changed
        $response = $next($request,$response);

        return $response;


Here is my Validator.php


namespace App\Validation;

use Respect\Validation\Validator as Respect;

//used for error checking see try catch block below
use Respect\Validation\Exceptions\NestedValidationException;


class Validator{

    protected $errors;

    //create validate method
    public function validate($request, array $rules){

        foreach($rules as $field => $rule){


                //helps pulling back error messages

            }catch(NestedValidationException $e){

                //append to error list see property. we pass in field var here to keep track
                //getMessages because there could be more than one assertion fail
                $this->errors[$field] = $e->getMessages();



        $_SESSION['errors'] = $this->errors;

        return $this;

    public function failed(){
        //return/check if the errors are not empty
        return !empty($this->errors);