Archive for the ‘software’ Category
Recently I’ve created the subj. It’s a memory game, written in pure PHP/HTML, called “PHP Memory”.
What was important for me to demonstrate is the next principles:
- Even if you don’t use a framework, you should write modular code with appropriate architecture.
- Despite that, the application design and code should match its required functionality with no overhead of unneeded patterns and abstraction or preparations for future enhancements, unless they’re planned.
- Nevertheless, the code should be readable and maintainable.
- The bottom line is – developing a framework versus developing an application are completely different tasks. The strategy and tactics should vary very much. Of course, developers should learn from the frameworks source code, since they accumulate collective experience of great coders, but the ideas implemented in frameworks sometimes not required or even harmful while developing an application.
Today we spent almost 2 hours on a weird discrepancy between our development and staging environments. It’s pretty rare, that I experience such low level issue, thus in my opinion it’s worth mentioning here.
Last weeks we were busy developing integration to a new data vendor. Everything went well until we deployed the application to stage.
Suddenly we started receiving HTTP status 411 on one of the calls. Since we work with cURL library, which we believed is stable enough, we thought the problem is somewhere between the source code and environment configuration.
Later we found that the same request gets accepted if sent from a client other than cURL (e.g. chrome-poster). The unique about this request is that it’s sent with POST method (the vendor’s strict requirement) but the content body is empty.
So, the immediate solution was to send empty content body (zero-length string) to cURL, which aligned the behavior in all the environments.
On the way we discovered a useful option CURLINFO_HEADER_OUT, which enables a possibility to further retrieve the headers sent by cURL to the remote host. From now we use it in our error handling mechanism to trace the sent headers as well.
What can we conclude from this story?
- Try to synchronize the software of all of your environments. If possible, use exactly the same version OS version, libraries, tools, etc. It’s very easy if you host your applications on VPS and use VMs for development and staging servers. The least convenient case is when you have OSs of different architecture and (e.g. Windows for development and Linux for production).
- Don’t underestimate importance of error handling. Find the optimal level of handling for your application, which will be easily extended and configured.
I love Ant integration into Eclipse JDT – it provides smart editor, handy auto-completion, and the most important – fully functional debugger.
Recently I have been laboring on porting a deployment system from shell scripts to Phing, a loose PHP port of Ant. And naturally, I miss the above. I still get a little aid from Eclipse – since Phing’s syntax is very close to Ant’s, I can at use Ant editor for Phing files to enjoy property navigation and target integrity validation.
I would be more than happy to announce that I’m going to fill the gap and implement Phing plugin for Eclipse PDT, but unfortunately – I’m too busy and too lazy. On the other hand, if you, my dear friend, will suddenly decide to accept this challenge, I can gladly invest my time in architecture, design, review & testing free of charge. Or should I anyway try to start it myself?
…When I was going to school we were always taught, “In the olden days of computing, computers were expensive and programmers were cheap. Now it’s the reverse. Therefore…” We are back to the future. At internet scale, programmers are (sometimes) cheap compared to the cost of electricity.