How to manage Codeigniter session with Ionic 3 application?

Code:

//main login function

function user_login(){



    //Allow Cross origin

    header('Access-Control-Allow-Origin:*');



    $username = $this->input->post('username');

    $password = MD5($this->input->post('password'));



    $data = array('status'=>false,'message'=>'','data'=>'');



    //check a session exists,if not create new

    if(!$this->session->userdata('username')){

        $user_data = array(

                'username' => $username,

                'attempts' => 0,

                'logged_in' => false

        );

        $this->session->set_userdata($user_data);

    }



    $attempts = $this->session->userdata('attempts'); //get number of tried attempts



    $this->session->set_userdata('attempts',($attempts + 1));//increse number of attempts from one







    {

        $lognError = $this->login_model->get_data_from_login_error_table($username);

        $b = true;



        if(sizeof($lognError) > 0){



            $trialsCount = $lognError['trials_count']; //get number of attempts that tried



            if($trialsCount >= 25){



                $b = false;

            }

        }



        if($b == true){



            $is_login = $this->login_model->login($username,$password);



            if($is_login != null) {



                $this->session->set_userdata('loged_in', true);

                $this->session->set_userdata($is_login);

                $this->session->set_userdata('user_details', $user_details);

            } else {

                $data['status'] = false;

                $data['message'] = 'Incorrect username or password';

            }

        }



    }

    // }

    echo json_encode($data);

}

Code:

public function is_login(){



    $details = $this->session->userdata('username');

    $is_loged_in = $this->session->userdata('loged_in');



    if(!$details || !$is_loged_in) {

        redirect('login');

    }

}