Reflections on installing TWiki

Yesterday, I spend some time installing TWiki wiki. Now in itself this is not special. However when reflecting on it, I (re)-learned an important lesson for developers. Let me explain.

Installing TWiki is fairly easy. Just follow the installation instructions. However, the no-extention files didn't seem to execute. The installation manual said that on some web servers the files need to be renamed to .pl or .cgi. So, I look in bin and see about 20 files without extension. I rename the first one, test it and it works.

I rename the second one and wonder. Renaming 18 files is a lot of work :) Should be able to be done faster. So renaming the first 2 back to the original name; I write some bash for loop to rename them all. Done!

I continue following the installation and done. The manual says> Just go to the login page. So I go there and... "internal server error". Not a very useful error message.

So reflecting on this, at this moment I have at least 2 choices.

• Figure out what is wrong
• Figure out what mistake I made

I guess I'm a typical programmer and I chose the first option, without thinking. So I spend an hour reading the web configuration, browsing the web forum, reading the perl code and nothing seems to be wrong. Thus I start editing the perl code and adding debugging messages to figure out on what line it generates the error. So after an hour... I find it! It cannot find a file called web.cfg (something like that). It's located in the bin directory....uhm... wait a second... in the bin directory? Yup. So... might it now have the name web.cfg.pl? Yup! Thats it! Just my mistake, I renamed the file by accident.

So, reflecting on this, I could have saved a lot of time. (On the other hand, I learned a lot of OTHER things during my debugging). What could be different?

• When being lazy and automating things, pay attention :) Might seem obvious but I've been making this mistake over and over again the last years.
• When something is not right, first think about what you could have done to break it. Not assume that the error is out there and not caused by your own actions. It's most probably because of my own mistake. So, I could have just traced back my steps and thought about where I could have made a mistake. The renaming of files would be one obvious place.

I'm not sure if I will ever learn these two simple guidelines. Still, I'll try :)