Most PHP developers have heard of the CURL extension for PHP or even used it. However it is mostly used in a basic form: to retrieve content from other websites or (RESTful) webservices. Ofcourse PHP itself offers several functions (like fopen or fsockopen) for getting this content, but they are all very basic. It is easy to run into limitations, for example you might want to define the request method or set another user agent (if you're building a webspider). This is where the curl extension kicks in. It is a separate library that has to be compiled with PHP in order to use it. The Curl extension has many functions and options which offer the developer more flexibility than the standard PHP functions.

Because we encounter PHP more and more in the enterprise market, the performance demands of websites we build are becoming ever more challenging. The usefulness of caching is often underestimated by developers (myself included). When using a lightweight framework like Code Igniter it is easy to assume caching is not needed or not necessary; still there are websites where performance optimization is needed and it is important to think about the performance and caching strategy beforehand. When writing the technical specifications for a high performance website the developer needs to be able to make the best choice for optimization.

For optimizing the performance of a website there are several techniques.The choice of the framework or CMS is important and the performance demands are a factor when determining which framework or CMS will be used, but it doesn't stop there.

Last month I took the PHP 5 Zend certification along with a colleague of mine. Ofcourse we both studied really hard (and actually learned something new!) and tried 2 practice exams. The practice exams were said to be harder than the actual exam and since I passed both practice exams I told myself that I need not to worry about the exam. But ofcourse, I still was nervous on the morning of the exam. My husband has tremendous faith in me and kept telling me don't worry, you will pass the exam.

Testen is een van de belangrijkste onderdelen in het proces van software ontwikkeling, maar is tevens hetgene dat het vaakst wordt vergeten of wordt overgeslagen vanwege tijdgebrek. Dit komt voornamelijk omdat het testen van software vaak wordt gezien als een handmatig klusje dat pas wordt uitgevoerd aan het einde van het proces, als het product volledig ontwikkeld is. Vaak is het dan zo dat er vanwege tijdgebrek geen tijd meer over is om alles goed te testen of het testen wordt maar half uitgevoerd.

Een oplossing voor dit probleem wordt beschreven in de XP (Extreme Programming) methode, namelijk het 'Test First' principe. Dit houdt in dat je alvorens te beginnen met programmeren nadenkt over hoe de software moet werken en hoe je dit kan testen. Vervolgens schrijf je dan eerst een zogenaamde unittest om een functie te testen (automatisch) en vervolgens ga je de functie implementeren.

De theorie klinkt allemaal leuk en aardig, maar werkt dit in de praktijk ook zo goed?