akrish

I’ve already briefly highlighted akrish.net’s structure in my previous post, but in this one I’d like to talk about some of the design strategies that I’ve used. Since I’ve already talked about how I read files, I’ll spend some time to briefly talk about how I’m writing into my xml files.

The first good design tactic I used was object oriented programming. So it’s really easy to use OOP in Java and some other languages, but in PHP it’s not the first thing that most people think about (at least I don’t). Yet it’s still really useful, because it allows you to compartmentalize all of your code into neat little objects that you can pass around and use really easily. So I have two classes: a Parser class and a Writer class. Both of them are for handling interactions between the web site and the xml documents that I’m using for feeds. The Parser object is pretty much what I explained in the previous post, except that it’s now an object. The Writer object has a function that writes a blog post into a specified xml feed, and that’s pretty much all it does right now. OOP is a lot better than functional programming in this case for a couple of reasons. First off, in the Parser object, all of the functions deal with an xml_parser object and so require an initialized xml_parser. This is easily solved by just iniitalizing one in the Parser constructor so that i’m only initializing the xml_parser once regardless of how many times I need to use it. Similarly parser functions need to know what feed to parse, but with OOP I can specify the feed in the constructor, rather than individually in each function. It prevents a lot of repetitive code. Another reason is that I can serialize objects and maintain all of their data as the user moves from page to page. I haven’t taken advantage of this yet, but I’ll need to it to allow a blogger to preview his/her new blog post. Anyway using objects makes the code a lot easier to read/change.

I also made the site highly modularized and functional. In addition to the objects, I also have a lot of functions that spit out content onto the pages. For example I have helper functions that spit out the html for the header, footer, and the navigation bars for all of the pages. These are really helpful, because I only have to make changes in one place, and the changes are propagated to the entire site. Furthermore, there’s a lot less code and a lot of my files end up having very little code, making everything easier for me to read later on.

I’ve also made change to how I show each feed, after realizing that I’d made a huge mistake. I used to have a separate file to show each feed (not the parser object, but each of these files calls the parser object and shows the content of the feed). This turned out to be a huge mistake because each of these files were the same except for which file name they passed to the parser. Anyway making changes got to be really tedious, because I’d have to make the same change on each of the files. I fixed this by making my index.php display all of the feeds. It selects a feed based on a parameter sent by HTTP GET. This is a lot better design wise for reasons that I’ve already mentioned.

Finally, the writer object is pretty straightforward. I set up an HTML form that’s password protected, with fields for feed, title, and body of the post. When I submit the form, I pass all of these parameters into the Writer. The Writer uses some simple regex’s to split up the text and add the proper xml tags. It then reads the old feed, and inserts the new xml into the old feed in the right place. Finally it re-writes the entire feed. I don’t think this is ultimately the best way to do it, because a lot of stuff stays the same in the file, and if the feeds get really long (which they may), this process may end up taking a while. For now it’s ok but I’m going to think about a better way to write xml files.

So that’s pretty much how this site is written. I do plan to add support for more tags, for example Image tags and Code tags so that I can style code differently will probably be added eventually. I don’t expect the rest of the back-end to change much so this’ll probably the last big post about akrish in here. Most of the other posts will probably be about wenote or any other ideas that I decide to execute. If you have any feedback about my design or if you’d like to see some features added, please let my know by commenting or by Thanks.