Technical Blog

Keeping the Drupal core and contributed modules up-to-date (at least on the security updates) is one of the essential steps for keeping a Drupal site safe and secure. Running updates of Drupal modules is usually a straightforward mechanism on a Drupal site that is done right. However what will you do if you do not know how things have been built? What will you do if some of the custom modules used are tied down to specific versions of some contributed module? What if there were custom changes on the site. Here is how you can run updates on a Drupal site almost completely safely.

We were testing our newly implemented modal popup for a login functionality. It was working pretty good in Firefox, Opera, and Chrome but not in IE8. When attempts to login by clicking on a login link the login modal was not appearing in IE8. Firebug said nothing, but jquery-1.7.2.min.js in IE showed the following error:

If you run a reasonably popular site there is a very good chance that you will get crawled by unscrupulous crawlers once in a while. The regular search crawlers from the popular search engines like the Google bot, Yahoo bot, Bing bot themselves are pretty intensive when they crawl sites but they do have limits on the number of pages crawled per visit and the number of simultaneous connections opened to your server. However there are lots of unscrupulous crawlers like spam bots, email harvesting bots and even some search engines who do not set any reasonable limits on the number of simultaneous connections to your server. There are hardware solutions that are available to prevent this but they may not be affordable for everybody. There is however a simple netstat based solution to prevent DDOS.

One of our clients sent us images they want to put in the website as pdf files. There were 100 files each containing a single image. Opening each of these in gimp and then saving it as pngs was a nightmare. For all such situations, ImageMagick is there for your rescue. With mogrify - a command utility available in the ImageMagick package, bulk converting all these pdf files to png was child's play.

On one of the maintenance projects we got we came across a page that used to take around 11 seconds to load. The page was a views listing for users. We were able to speed up the page load times from around 11 seconds to under 3 seconds by taking out just the distinct option used in the view. The following was the select query that was originally generated from the view with the time logged by views in the preview panel.

In every operating system, there are a lot of tasks that need to be scheduled to run at a particular time - some, very often (as in, every 5 minutes), and some, less (like, once every month). For a quick example, you might want to run a temporary files deletion operation at midnight each day - this is where you need to write a cron job.Crontab and Cron jobs are Linux’s version of a complete job scheduling system.Let us see these in detail.

Boost is a module in Drupal that enables file based static page caching in Drupal. When an anonymous user visits a page for the first time in a Boost-enabled Drupal site, the page will get stored as a static html file in a cache folder. When the next anonymous user visits the same page the htaccess rules created by Boost will serve the static file cached in the cache folder instead of bootstrapping drupal for generating the page. This saves a lot of processor usage and would help even entry level hosting servers serve reasonably good volume of traffic. Here is how you can install and configure Boost in a Drupal 6 site.

We recently saw this error on a Drupal 6 site that had not been updated for quite a while."warning: call_user_func_array() expects parameter 2 to be array, string given in sites/all/modules/contrib/views/views.module" means what it says. call_user_func_array expects the second parameter to be an array whereas a string was given instead. You can troubleshoot problems like this by writing a bit of debug code before the line where the error is reported.

Drupal’s Nice Menus Module provides a highly customizable and nice-looking dropdown menu for Drupal websites. To allow maximum customizability, it includes a CSS file and a javascript file where you can try out your own recipes. The following steps should help you make nice looking drop down menus for your Drupal website using the Nice Menus module:

Have you ever wondered how that cool site you saw last day had those cool interfaces and you wished your Drupal site could have the same coolness? jQueryUI is your saviour here. jQueryUI is one of the most popular JavaScript libraries out there in the world of web development. jQueryUI allows you to add very cool user interface elements to your website without much effort.

Solution for CKEditor not working in a Drupal 6 site. One day, all of a sudden we found out that the CKEditor was not working on our Drupal 6 site. It had literally disappeared from our website taking the whole text area on the edit page with it. This meant that we could not create any articles as long as the CKEditor was not working. On seeing this, the first thoughts that flashed through our head was to either update the module or apply a patch believing that the CKEditor module had crashed. However our fears were unfounded and the solution turned out to be more simple than we expected.

Developing a Drupal website is a complicated and long process. You have to check whether all the design and functionalities meet with the client specifications. And before the site going to be live you have to check certain criteria.These checklists describes the criteria that should be tested before a site going to be live.

Password-protecting drupal development site with .htaccess file There might be few scenarios when we need to protect our site from the general public and make it accessible to a selected group of users. One of the most common scenarios in the development workflow of a Drupal site is when you want to avoid your half-complete drupal site showing up in Google search results.For such needs, it is advisable to go for password-protecting the site using HTTP authentication. If you have cPanel installed on your hosting server, you can use the ‘Password Protect Directories’ option from the ‘Security’ section on the cPanel home page. Click here to read on How to enable HTTP Authentication using cPanel (link to an article for the same on our site) For those without cPanel, here’s how to get Apache work your way:

A VPS lies somewhere in between shared hosting and dedicated servers in terms of the features it provides. VPS divides the server’s primary resources and gives you certain amount of diskspace, memory, processing speed and bandwidth, with freedom on the OS configuration. In the case of shared hosting its like a common pool from which you consume bandwidth, diskspace, and processing power until it is exhausted. You dont get much control over the OS config.