Asmir Mustafic has continued his series looking at building modular applications with part five looking specifically at some of the considerations and ideas to keep in mind when developing your modular applications.

This is the fifth post from a series of posts that will describe strategies to build modular and extensible applications. In this post we will take a general overview on how some popular design patterns and things to keep in mind when creating plugin based applications.

[...] Anthony Ferrara (alias ircmaxell), in this post blogged about the use of software patterns to implement plugin-based architectures. It is a great article and I suggest everybody to read it. As it is clear from the article, each of this software patterns has a specific use case and the choice of which one to use depends on which the of integration we want allow for the future plugins.

The article starts with a brief recap of some of the more common design patterns including the Observer, Strategy, Decorator and Chain of Responsibility. It then covers some quick uses of these patterns and shares two tips when developing a plugin system for the application and links to good examples for reference.

Robert Basic has a post to his site covering interfaces and their use in PHP, including what to consider when creating effective interfaces.

Creating and implementing interfaces in our code is important. It helps with swapping out components, eases testing, separates the what from the how.

But, it’s not enough just to slap an interface on a class and be done with it. We also need to consider on what are we putting that interface on.

He starts with an example of a feed (RSS) reader where an interface defines a queue handler with an add method. Eventually he makes some decisions and implements the queue in a concrete class but points out that there's something "fishy" about the example. He covers the three issues he sees including the class doing two things and how it locks the functionality into the queue. He refactors the example, abstracting things out to more correctly adhere to the Single Responsibility Principle and split out the database handling from the queue functionality.

In a new post to his blog today Gonzalo Ayuso offers some tips for those out there wanting to cluster their PHP applications effectively.

Sometimes a web server and a database is fair enough to meet our project requirements. But if the project scales we probably need to think in a clustered solution. This post is an attempt at being an unsorted list of ideas working with clustered PHP applications. Maybe more than a list of ideas is a list of problems that you will face when swapping from a standalone server to a clustered server.

He touches on a few different topics you might need to consider:

• consistency in source code
• writing to the file systems
• deployment problems
• authentication/authorization issues
• handling sessions/logs/cache files

On the Ibuildings techPortal site Stefan Koopmanschap has written up some thoughts on one of the eternal struggles development shops face - whether to buy or build the software they need (either for themselves or their clients).

One of the biggest struggles in any software development company is "Buy vs. Build". How do you strike a balance between writing custom software and purchasing off-the-shelf solutions. This is something that is very hard and everyone gets it wrong every once in a while. In this article we will explore the way that Ibuildings approaches this issue, in the hopes that it helps others in getting it right more often.

He talks about considerations made on both sides - how flexible is the application, what is on-hand that could be adapted - and how the base product they might have purchased can act as a based to work from (like a content management system). There's no overall recommendation, though - too much of the decision depends on what's needed at the time and the capabilities of the technical staff employed.

On the NETTUTS.com website, there's a great article with some "essential security considerations" that you can use to see just how hackable your site could be.

This article walks through the brainstorming stage of planning for what is in this instance, a hypothetical user-centric web application. Although you won’t be left with a complete project – nor a market ready framework, my hope is that each of you, when faced with future workloads, may muse on the better practices described. So, without further ado...Are you sitting comfortably?

The tutorial is broken up into a few sections based around an example with a few points of failure (about book information). They work through the thought process behind the code, using the $_REQUEST variables correctly, preventing SQL injections, filtering the HTML output and a sample code download for you to see how it's all tied together.

The International PHP Magazine has conducted a poll over on their website, asking visitors what their top considerations were for choosing and working with a CMS. They've posted the results of that poll today.

The options provided for the poll were:

• How is it licensed?
• What is the language/environment?
• How long has it been around?
• Is it actively developed?
• Who is using it?
• Is there support?

The results show an overpowering victory for the "actively developed" category, with the licensing and language requirements tying for second place. The option the least number of people cared about? Who was using it...

The International PHP Magazine has conducted a poll over on their website, asking visitors what their top considerations were for choosing and working with a CMS. They've posted the results of that poll today.

The options provided for the poll were:

• How is it licensed?
• What is the language/environment?
• How long has it been around?
• Is it actively developed?
• Who is using it?
• Is there support?

The results show an overpowering victory for the "actively developed" category, with the licensing and language requirements tying for second place. The option the least number of people cared about? Who was using it...