Codeigniter and AJAX error - php

Question

I am making an application for a bar.
The application populates #beer_output with "beer form buttons" by executing get_beers_from_customer(); when the document is ready.
Then the bartender serves drinks by clicking on a "beer form button".
Each time the bartender clicks on the "beer form button" an ajax call is made and send to the codeigniter controller where the beer is deleted and echos a response to ajax with the beers left to be served until there are no orders left to be serve.
Once there are no beers left the order gets processed through another function of my controller : process_order_when_all_drinks_served($user_id).
I am using authorize.net as the payment gateway.
The problem is when I order only 1 beer to be serve, but if I have an order of 2 beers everything works fine. process_order_when_all_drinks_served($user_id) outputs the error Trying to get property of non-object.
Here is specifically where the error is happening if($response->response_code=="1") apparently it is not giving a response back. The ajax is posting and it is not giving back any errors. I do not know what is happening. I can give you the link and order 1 drink if that helps.
Here are the ajax functions
$(document).ready(function(){
get_beers_from_customer();
function get_beers_from_customer()
{
//form variables
var user_id = "<?php echo $this->session->userdata('user_id'); ?>" ;
var formData = {user_id:user_id};
ajax_update_content_when_page_is_loaded_beers(formData);
}
function ajax_update_content_when_page_is_loaded_beers(formData)
{
$.ajax({
url : '<?php echo base_url()."index.php/bartender/bartender_serve_beers"; ?>',
async : false,
type : "POST",
cache : false,
data : formData,
dataType: "html",
success : function(data)
{
alert($.trim(data));
$('#beer_output').html($.trim(data));
$('#beer_output').trigger('create'); },
error: function (jqXHR, textStatus, errorThrown)
{
$('#server_message_error_jqXHR').html("here is the jqXHR"+jqXHR);
$('#server_message_error_textStatus').html("here is the textStatus "+textStatus);
$('#server_message_error_errorThrown').html("here is the errorThrown"+errorThrown);
}
});
}
});
once the form is submitted
$(".beer").on("submit",function(event)
{
//variables
var delete_beer = $(this).find(".delete_beer").val();
var beer_id = $(this).find(".beer_id").val();
var user_id ="<?php echo $this->session->userdata('user_id');?>";
// alert( "delete_beer="+delete_beer+"beer_name=" +beer_name +"beer_id="+beer_id );
//form variables
var formData = {delete_beer:delete_beer,beer_id:beer_id,user_id:user_id}; //Array
submit_ajax_form_beers(formData);
//get_beers_from_customer();
});
function submit_ajax_form_beers(formData)
{
$.ajax({
url : '<?php echo base_url()."index.php?/bartender/bartender_serve_beers"; ?>',
async : false,
type : "POST",
cache : false,
data : formData,
dataType: "html",
success : function(data){
$('#beer_output').trigger('create');
console.log($(this).data(formData));
},
error: function (jqXHR, textStatus, errorThrown){
$('#server_message_error_jqXHR').html("here is the jqXHR"+jqXHR);
$('#server_message_error_textStatus').html("here is the textStatus "+textStatus);
$('#server_message_error_errorThrown').html("here is the errorThrown"+errorThrown);
}
});
}
Codeigniter controller
public function process_order_when_all_drinks_served($user_id)
{
$bartender_id = $this->session->userdata('bartender_id');
//load model
$this->load->model('authorizenet_model');
//finalize order with authorizenet prior authorize and capture
$response = $this->authorizenet_model->priorauthcapture($user_id);
print_r($response);
if($response->response_code=="1")
{
//stores the order_line before it is deleted
$this->bartender_model->store_past_order_line($user_id);
//deletes customer from order line if all beers and mixed drinks have been served
$this->bartender_model->delete_customer_from_order_line($user_id);
//order was successful
$response_message= '<center><strong>'.$response->response_reason_text.'</strong></center>';
}
else
{
//store userdata in unprocess orders
$this->bartender_model->store_unprocessed_order($user_id,$bartender_id);
//then erases it from order_line
$this->bartender_model->delete_customer_from_order_line($user_id);
$response_message= '<center><strong style="color:red;">'."There was a problem with the order.<br/>"
.$response->response_reason_text.$response->error_message.'</strong></center>';
}
return $response_message;
}
public function bartender_serve_beers(){
//checks if there are any drinks left to process order
if(isset($_POST['delete_beer']) && isset($_POST['user_id'])
{
$user_id = $_POST['user_id'];
$beer_id = $_POST['beer_id'];
//then it is deleted from the paid beers
$this->bartender_model->delete_beers($user_id,$beer_id);
//checks if there are any drinks left to be processed
$checks_any_drinks_left= $this->bartender_model->checks_if_mixed_drinks_beers_left_to_process_order($user_id);
if($checks_any_drinks_left=="1")
{
$user_id = $this->session->userdata('user_id');
$proccess_drinks_message= $this->process_order_when_all_drinks_served($user_id);
//outputs the response message to bartender
echo $proccess_drinks_message;
}
else
{
$user_id = $this->session->userdata('user_id');
//continues outputting beers
echo $beers_served_button = $this->bartender_model->output_beers_served_button($user_id);
}
}
else
{
$user_id = $this->session->userdata('user_id');
echo $beers_served_button = $this->bartender_model->output_beers_served_button($user_id);
}
}

Answer 1

I don't see nesessity to have output of session variable to frontend.
You will have it in next controller too. Better would be to check in next controller if it still exists.
Add one check in inside else like:
//...
else if ($this->session->userdata('user_id') != false && !empty($this->session->userdata('user_id')) ) {
$user_id = $this->session->userdata('user_id');
//continues outputting beers
echo $beers_served_button = $this->bartender_model->output_beers_served_button($user_id);
}//...rest of the code
Also, you check for $_POST['delete_beer'] and than assign $_POST['beer_id'] to $beer_id variable. Although I can't see you passed any beer variable through AJAX. As far as I can see, you pass only session output.