In OpenCart (OC), extending your site's features usually results in modifying the program core codes. There are many reasons why this practise in not favorable - a major one is that it is not easily reversible. Say when you modified some codes and wanted to reinstate the original for some reason, it can be quite tedious.

This is due to the nature how OC handles extensions. Its normally done by overwriting existing codes instead of using plugin or module concepts employed in WordPress or Drupal. Honestly, this has been one of my top gripes about OC. I quit using OsCommerce for this very same reason years ago. Well, I love most of what OC has to offer so I have to live with it for the time being .

But all is not lost - there is a rescue!

Recently I notice a lot of people were talking about vQmod and OC ver 1.5 supports it. Interestingly, vQmod was originally developed for OC! But due to "openess" of the design, it has been used by other systems too.

So What Is vQmod?

Nobody can offer a better answer to this question other than the people at vQmod and this is what they have to say:

"vQmod™" (aka Virtual Quick Mod) is an override system designed to avoid having to change core files. The concept is quite simple... Instead of making changes to the core files directly, the changes are created as xml search/replace script files. These script files are parsed during page load as each "source" core file is loaded with the "include" or "require" php functions. The source is then patched with the script file changes, and saved to a temp file. That temp file is then substituted for the original during execution. The original source file is never altered. This results in a "virtual" change to the core during execution without any actual modification to the core files.

In a nutshell, you don't mess up with the core files while doing modifications but the same result is achieved at the end. According to the developers, the impact to the overall site performance is negligible. You can read more details at vQmod.

Installing vQmod on Opencart 1.5

1. Download the latest version that has "OpenCart" in the title from vQmod Installation
2. Unzip using 7zip or your favorite zipper
3. Using FTP, upload the "vqmod" folder to the root of your Opencart store
4. Be sure the vQmod folder and the vqmod/vqcache folders are writable (755)
5. Enter http://www.yoursite.com/vqmod/install into your internet browser
6. You should get a success message. If not, check permissions above and try again
7. Load your store homepage and verify if it works
8. Using FTP, verify that there are new "vq" files in the "vqmod/vqcache" folder. This folder is empty before installation

Using vQmod

Typically this step is easier than the installation above. Please note that NOT all OC Extensions are meant for vQmod so those that are compatible are marked as such. While you're at OC Extension page try exploring the "vQmod" category and you'd see a list of extensions with vQmod version.

1. Upload file you want to install, upgrade or update, the file shall be under c://vqmod/xml/ (should be unzipped).
2. Look for /xml directory and move entire /xml directory to root directory (/www/) or select the files and move to /www/xml/ directory.
3. In most cases, you need to assign "permission". Do this in "systems/users/user groups".
4. Look in the dashboard for your new feature.

While Vqmod is somewhat helpful, OC still doesn't support full "auto-install & auto-upgrade" of extensions as seen in WordPress, Joomla, Drupal and many others. There are still "manual" file handling tasks to be carried out using FTP etc. My hope is that OC will be more at par comparing to other platform in this respect so that we all can be more productive.

Finally, while the are benefits in using vQmod, it might not be suitable to all your needs so use it with care .

Anything you'd like to point out? Just leave us a comment below.