Rob Golding

The country has just undergone a mass-exodus of university students from their parents’ houses back into halls. I played by own small part in blocking up the roads moving back into university accommodation this weekend, and it’s all gearing up for the new school year.

I’ve been working with Django more and more lately, and I’ve written my first “commercial” application using my new favourite framework – a booking system for taught causes at the City Council. I’m really enjoying writing web applications with Django, and I’m sure this blog will start to resemble a web-developer’s in the near future.

Also, I’m really looking forward to this year at university. As I understand it, there’s a lot more work to be done, but the software engineering group project should be fun – as long as my “randomly chosen” team are happy with us using Python!

I just finished my last exam today – Web Programming and Scripting – which explains the distinct lack of activity around here in recent times. Thankfully I could end my exam season on a high, as web programming is, well, what I do – so it wasn’t too much of a challenge!

Something strange happens to me every time exams come around. I seem to pick up new projects, and just run with them. This time, I’ve become involved with a small group of people at university, writing a portal-style information system for universities. I suppose most people call this behavior procrastination, but I’m quite deeply in denial about that.

Ever since my post about the Backtrac Backup System, I’ve been really enjoying using Django. Something about it just makes developing for the web, well, exciting. That can only be good, right? I am the designated server administrator for this latest project, mostly due to the fact that I am the only one with a server to administer, and some of the things I’ve learned so far seem worthy of a mention here.  Firstly, we as developers were – how can I put it – stepping on each other toes somewhat. The project at this point had no version control, so we were just editing a bunch of files over SFTP. Obviously, some sort of Source Control Management was in order. I did some research, and decided that Git was a nice, modern alternative to the ever-popular SVN. It also meant that my server was constantly backed up by everyone on the team – but that’s just a bonus!

So, I installed Git, and started a repository. A lot of effort went into learning how the system works, and more importantly, how to make it work for us. Directed Acyclic Graphs thankfully made some sense to me, so I could just about understance the documentation. I wrote some custom hooks, and a C Program to syncronise the web-server. I was happy, and absolutely certain that this was the solution to all our woes. I was mistaken. Git just didn’t work the way I had hoped. The custom hooks were throwing permission errors all over the place, and my development team (read: my friend Rob Miles) was locked out of the repository. We made the decision yesterday to scrap Git, and go back to the previous system of editing the files over SFTP. We are always in constant communication when developing for the project, so it’s not too big a deal, but I feel that I failed as an adminisrator. You see, as an admin your job isn’t just to play with cool toys and loud servers – your primary purpose is to give the users what they need to work, and that is most certainly not what I achieved.

I’m glad I took the time to learn Git – and I’m sure it will help me later in life, in some way or another. It’s just unfortunate that it didn’t work out the way I had hoped for our project.

My life has been pretty busy as of late, mostly with a new project I am working on called BackTrac. I am developing a network backup solution, written entirely in Python – using the Django framework as a front-end web interface.This came at quite a good time, as I’ve been asked to give a presentation on any highly technical topic, on which I know my stuff. The plan is to use BackTrac as a base, and to explain the technical concepts behind the system that make it work. The things I am going on concentrate on are:

• Pyhon in general
• XML-RPC
• Filesystem hardlinks
• The MVC concept, and Django

This should be enough content to fill a 15-minute slot, I hope.

Now I’ll explain a little bit about how BackTrac works, for the benefit of those not coming to the presentation.

What I wanted to achieve with BackTrac was a smart backup system, that doesn’t necessarily have to be the fastest. I wanted a very detailed web interface, with scheduling capabilities and log view. I decided on Django for this, seeing as I had already decided on Python for the system itself.

The nodes in the system use XML-RPC to communicate, and SMB for the actual file-copying. The real bonus of this system is that it takes advantage of a little-understood feature, present in most modern filesystems, called hardlinks. Hardlinks enable the user to essentially point to the same piece of data on a disk from more than one position. Essentially the concept is that if a file has been backed up before, why back it up again? Just create a link or “shortcut” (a hardlink) to the previously backed-up file. This is the basis for BackTrac.

Also, Django is turning out to be a real treat. This is the first time I have used an MVC like Django, and I’m really enjoying it. Web development is exciting again! I do agree with one point however, that Django makes the easy things easy, and the hard things impossible. Not quite impossible in my case, but I’ve had to do some pretty strange things to get Django to do what I want.

Finally, I’ve had the BackTrac project approved on Sourceforge.net, so watch out – I’ll be doing the initial import soon and getting some web content online. First though, I have to decide on the best way to distribute the application. This is a bit more complicated than it might otherwise be, because there are three different aspects of the system – the client application, the server application, and the Django project. On this topic or any other, as usual, opinions are most welcome.

For the first time in 7 months, I’ve finished writing a new article for my resource site – maxms.net. The article is entitled Folder Redirection with Group Policy in Server 2003 – it’s purpose should be explained fully in the title!

If this helps just one person out there, I will be happy. I’d be even happier if they contacted me to let me know it helped . I hope this will signal a revival for the site, and I shall continue writing more articles as time allows. Any suggestions for future articles are welcome, just shoot me an email with the contact button up top.

For a direct link to the article, and some shameless self-promotion: Folder Redirection with Group Policy in Server 2003

I don’t know whether this is a popular or well-heard-of problem or not, but I have come across this twice now. The phpBB forums over at maxms.net have suffered the second “White Screen of Death” incident since I installed them. Firstly, I disabled Gzip compression to fix the issue. This time though, it wasn’t so easy.

I ended up being forced to reinstall the same version of phpBB to another directory on the server, into a new database. Then I renamed the new DB to something different, and changed the old one to the new one’s name. Phew! So in the end, I had a new install of phpBB, but with the same data as before – and it worked perfectly.

So if anyone else comes across this issue, firstly try disabling HTTP compression on any device in front of the web-server (which for me was MS ISA Server 2006). If that doesn’t work, it looks like it has to be a reinstall – the longest process will be renaming the DB’s, however, so be careful.

Anyhow, the forums are now back up and running – at forums.maxms.net. Hopefully this seemingly endless list of problems to fix is over now.