Login_Model.php

<?php if (!defined('BASEPATH'))
{
    exit('No direct script access allowed');
}
class Login_model extends MY_Model
{
    public $table = 'user';

    public function getValidationRules()
    {
        $validationRules = [
            [
                'field' => 'username',
                'label' => 'Username',
                'rules' => 'trim|required'
            ],
            [
                'field' => 'password',
                'label' => 'Password',
                'rules' => 'trim|required'
            ]
        ];

        return $validationRules;
    }

    public function getDefaultValues()
    {
        return [
            'username' => '',
            'password' => ''
        ];
    }

    public function login($input)
    {
        $input->password = md5($input->password);

        $user = $this->db->where('username', $input->username)
                         ->where('password', $input->password)
                         ->where('is_blokir', 'n')
                         ->limit(1)
                         ->get($this->table)
                         ->row();
        if (count($user))
        {
            $data = [
                'username'  => $user->username,
                'level'     => $user->level,
                'is_login'  => true
            ];

            $this->session->set_userdata($data);
            return true;
        }

        return false;
    }
    public function logout()
    {
        $data = [
            'username'  => null,
            'level'     => null,
            'is_login'  => null
        ];
        $this->session->unset_userdata($data);
        $this->session->sess_destroy();
    }
}