Miro's Blog

Over the past few months, we've been working extensively with the PHP CodeIgniter framework. One thing that consistently slowed me down during debugging was the repetitive process of logging variables. Every time I needed to log a variable, I found myself typing out log_message('error', $your_variable) —a lengthy 18 characters every single time! And that’s just for basic variables. If I wanted to log a boolean, object, or array, the process became even more time-consuming, often requiring additional if statements or extra formatting. To simplify this process, I decided to write a small custom log helper. This helper makes logging easier by automatically handling different variable types, allowing for faster and more efficient debugging. If you’re working with CodeIgniter and find logging as tedious as I did, you might find this helper useful too. <? if ( !function_exists('l') && !function_exists('l2') && !function_exists('ge...

The Problem Recently, at work, we encountered a puzzling issue with our web application, which was built using the CodeIgniter PHP framework. Users were being logged out unexpectedly, and the logout behavior was irregular and hard to predict. Although we noticed this problem early on, it was difficult to reproduce consistently, making debugging a challenge. The issue seemed random, but we eventually observed that it occurred more frequently when the screen displaying a map of POI (Points of Interest) positions was refreshed at short intervals, such as every few seconds. What Was the Cause? Initially, we suspected the session was expiring prematurely. However, upon closer inspection, we discovered that the session cookie was being truncated—losing about 10 to 20 characters. This led us to investigate the CodeIgniter Security class, specifically the xss_clean function, which is designed to prevent cross-site scripting (XSS) attacks. The root cause was a regular expression within xss_cle...