Opencart cart across multiple stores with different subdomains - session

Question

Hi have a single opencart install setup with several stores with different subdomains (all under the same domain). I want customers to be able to put items in the cart on one site, then move onto the next and put in more or even subtract, till eventually a customer checkouts out on any store. Note products might appear in one store but not another.
I notice opencart does this somewhat. ie it will bring products already in the cart to the next store but only if the products appear in both stores. Further if a customer then deletes one of the items and moves back to the same store, they product reappears.
First Problem seems to firstly be products in the cart are being displayed through what i guess is a query that selects products by store_id. I have had a hard look to see if i can find anything but am at a loss.
Second problem seems to be with the contents of the session. I am still learning php and am a bit confused of how to even attempt to modify how the session works.
Can anyone please provide some guidance on how i can go about fixing/changing this.

Answer 1

OpenCart stores all these information in you PHP session. Since your stores are located under different subdomains, the PHP session changes when you switch from one store to another.
So the first thing you need to do is to share the session between all subdomains. By default, PHP uses the 'PHPSESSID' cookie to propagate session data across multiple pages, and by default it uses the current top-level domain and subdomain in the cookie declaration.
Example: www.domain.com
The downside to this is that the session data can't travel with you to other subdomains. So if you started a session on www.domain.com, the session data would become unavailable on forums.domain.com. The solution is to change the domain PHP uses when it sets the 'PHPSESSID' cookie.
Assuming you have an init file that you include at the top of every PHP page, you can use the ini_set() function. Just add this to the top of your init page:
ini_set('session.cookie_domain',
substr($_SERVER['SERVER_NAME'],strpos($_SERVER['SERVER_NAME'],"."),100));
This line of code takes the domain and lops off the subdomain.
Example: forums.domain.com -> .domain.com
Now, every time PHP sets the 'PHPSESSID' cookie, the cookie will be available to all subdomains!
You might also need to make some little modifications to the OpenCart's core in order to make it work.
Have fun :)

Answer 2

After Tohids help I have the following solution, hopefully it helps others. I added the cookie_domain code line to the session.php file and also added or changed the cookie name wherever the setcookie function was used to cover the currency and language cookies.
open \system\session.php
find;
ini_set('session.use_cookies', 'On');
ini_set('session.use_trans_sid', 'Off');
insert after;
ini_set('session.cookie_domain', substr($_SERVER['SERVER_NAME'],strpos($_SERVER['SERVER_NAME'],"."),100));
open \index.php
find;
if (!isset($request->cookie['language']) || $request->cookie['language'] != $code) {
setcookie('language', $code, time() + 60 * 60 * 24 * 30, '/', $request->server['HTTP_HOST']);
}
replace with;
if (!isset($request->cookie['language']) || $request->cookie['language'] != $code) {
setcookie('language', $code, time() + 60 * 60 * 24 * 30, '/', substr($_SERVER['SERVER_NAME'],strpos($_SERVER['SERVER_NAME'],"."),100));
}
find;
if (isset($request->get['tracking']) && !isset($request->cookie['tracking'])) {
setcookie('tracking', $request->get['tracking'], time() + 3600 * 24 * 1000, '/');
}
replace with;
if (isset($request->get['tracking']) && !isset($request->cookie['tracking'])) {
setcookie('tracking', $request->get['tracking'], time() + 3600 * 24 * 1000, '/', substr($_SERVER['SERVER_NAME'],strpos($_SERVER['SERVER_NAME'],"."),100));
}
open system\currency.php
find;
if (!isset($this->request->cookie['currency']) || ($this->request->cookie['currency'] != $currency)) {
setcookie('currency', $currency, time() + 60 * 60 * 24 * 30, '/', $this->request->server['HTTP_HOST']);
}
replace with;
if (!isset($this->request->cookie['currency']) || ($this->request->cookie['currency'] != $currency)) {
setcookie('currency', $currency, time() + 60 * 60 * 24 * 30, '/', substr($_SERVER['SERVER_NAME'],strpos($_SERVER['SERVER_NAME'],"."),100));
}

Answer 3

Very Easy Solution! Share the login session across the subdomains
OPEN FILE: system/library/session.php
FIND LINE: session_set_cookie_params(0, '/');
APPEND : session_set_cookie_params(0, '/','.DOMAIN.COM);
Make sure to include the period "." before DOMAIN.COM
That's it... Now login sessions started on www.domain.com is shared with www.sub.domain.com