Codeigniter 3 validation error not showing along with callback function - codeigniter

Question

I want to validate login form with ajax. I am using form valiation with a callback function that check username in database. When I am using callback with set_message, form validation errors are not working, only that callback error message is shown. If username is empty then form validation error like "Username is required" should be shown first and then if user enter wrong username then callback function error like "Username is not correct" should be shown
Following are the functions in my controller
public function validate_form()
{
$data = array('success' => false, 'messages' => array());
$this->form_validation->set_rules('username', 'Username', 'required|trim|xss_clean|callback_username_check');
$this->form_validation->set_rules('password', 'Password', 'required|trim|xss_clean|callback_password_check');
$this->form_validation->set_error_delimiters('<p class="text-danger">', '</p>');
if ($this->form_validation->run()) {
$data['success'] = true;
$this->session->set_userdata('admin_username', $this->input->post('username'));
} else {
foreach ($_POST as $key => $value) {
$data['messages'][$key] = form_error($key);
}
}
echo json_encode($data);
}
public function username_check()
{
$username = $this->input->post("username");
if ($this->admin_model->usernameDB()) {
return true;
} else {
$this->form_validation->set_message('username_check', 'The {field} is not correct');
return false;
}
}
public function password_check()
{
$password = $this->input->post("password");
if ($this->admin_model->passwordDB($password)) {
return true;
} else {
$this->form_validation->set_message('password_check', 'The {field} is not correct');
return false;
}
}
Following are the function in my model
public function usernameDB() {
$this->db->where('username', $this->input->post('username'));
$query = $this->db->get('adminuser');
if ($query->num_rows() == 1) {
return true;
} else {
return false;
}
}
public function passwordDB() {
$this->db->where('password', md5($this->input->post('password')));
$query = $this->db->get('adminuser');
if ($query->num_rows() == 1) {
return true;
} else {
return false;
}
}
Following is the ajax that i am using
$("#admin_login_form").submit(function(e) {
e.preventDefault();
var me = $(this);
// perform ajax
$.ajax ({
url: "validate_form",
type: "post",
data: me.serialize(),
dataType: "json",
success: function(response) {
if (response.success == true) {
$('.form-group').removeClass('has-error')
.removeClass('has-success');
$('.text-danger').remove();
window.location = "member";
} else {
$.each(response.messages, function(key, value) {
var element = $('#' + key);
element.closest('div.form-group')
.removeClass('has-error')
.addClass(value.length > 0 ? 'has-error' : 'has-success')
.find('.text-danger')
.remove();
element.after(value);
});
}
}
});
});
I want proper validation errors order like if username or password is empty then first their relevant errors should be shown like username or password is required and then wrong or correct username or password errors should be shown.

Answer 1

You can try below. You can use single callback function to check whether user is exists or not.
First, remove the callback functions public function username_check() and public function password_check() from your controller and replace with the updated functions below.
In addition to this created new model function login inside admin_model which will check whether user is exists or not. Also you can delete both usernameDB and passwordDB from your admin_model.
Controller function:
public function validate_form()
{
$data = array('success' => false, 'messages' => array());
$this->form_validation->set_rules('username', 'Username', 'required|trim|xss_clean');
$this->form_validation->set_rules('password', 'Password', 'required|trim|xss_clean|is_user_exists');
$this->form_validation->set_error_delimiters('<p class="text-danger">', '</p>');
if ($this->form_validation->run()) {
$data['success'] = true;
$this->session->set_userdata('admin_username', $this->input->post('username'));
} else {
foreach ($_POST as $key => $value) {
$data['messages'][$key] = form_error($key);
}
}
echo json_encode($data);
}
public function is_user_exists()
{
if ($this->admin_model->login($this->input->post('username', TRUE), $this->input->post('password', TRUE))) {
return true;
} else {
$this->form_validation->set_message('is_user_exists', 'Login failed. Username or password is incorrect');
return false;
}
}
Model function:
public function login($username, $password)
{
$this->db->where('username', $username);
$this->db->where('password', md5($password));
$query = $this->db->get('adminuser');
if ($query->num_rows() > 0) {
return true;
} else {
return false;
}
}
Note: Using md5 for encrypt password is not good. See Alex's comment for more details.