If you’re a Twitter user, you’re probably familiar with this image:

It is/was the default profile image for users that have not uploaded a custom avatar. You may also have noticed last week that Twitter has introduced a new version. Actually they they made seven of them in different colours:

At least I think they made seven; I can’t find any more, but I can’t find any official document stating how many are out there either.

So what?

So … TwitBlock crawls Twitter for duplicate profile pics to help identify spam accounts. The app needs to know what images are the default ones, because otherwise it will penalize people heavily for having what appears to be the same image as thousands of other people.

This relies rather delicately on factors that are liable to change and that aren’t strictly a part of the developer API, so I have to keep a close eye on things. I concede this is not a very robust solution, and I certainly wouldn’t base a commercial product around such weak “technology”. In fact I’m not sure I’d base a commercial product around Twitter at all.

I get a lot of emails and DMs from people telling me that they’ve received errors using TwitBlock. Almost always this is due to the Twitter API failing to respond – either timing out or sending back some HTTP error. It’s quite embarrassing, and I can only imagine how much worse this would be if people were paying for a Twitter-based service.

A Twitter app doesn’t just rely on the API, it relies on everything that makes up the Twitter service. This includes its full feature set and its hardware infrastructure. I am of the opinion that the above-described profile image change was significant enough that Twitter should have documented the change in advance. Facebook do a good job of addressing the community far in advance of changes, and I think this is yet another indicator that Twitter is out of its depth.

1. 1&1 suck like it’s going out of fashion
   
2. The only backup is a full disk image backup
3. I am not a Linux sysadmin

And finally a lesson for 1&1 .. good customer service is about exceeding expectations not covering your arse*.

1. I had a budget root server with 1&1 internet for about 5 years. Apparently about a month ago 1&1 emailed me stating that they were going to physically move my server, and that they would not be responsible for any data loss during that time. I say apparently because I don’t remember it. It’s quite likely I thought it was a marketing email and trashed it without a second look, or maybe it got junked… who knows.

Anyway,  they switched my server off, moved it, and switched it back on. The hard disk which was running for 5 years basically had a heart attack and died. I was told by a 1&1 call centre chap that “this is expected”, and of course they don’t back it up for you.

2.  Fortunately I was backing up my databases using a home-made combination of mysqldump and [the fabulous] rsync, but it was only my personal server for tinkerings such as this blog, so I wasn’t paying for a full mirror. ( Error ). Not only was there an absolute tonne of software, and highly custom configurations, but I had totally forgotten to backup the file uploads on this blog. ( s%&t! ). So I’m really sorry for the 404s, especially on my most popular post, where the demo files are currently AWOL; I shall work on reinstating these, because half my traffic goes to this article.

This blog is now running on a small VPS at Slicehost. and for $5 per month I keep a daily, weekly and adhoc mirror of the complete image. Marvelous :)

 3. I am a web developer, not a Linux sysadmin, but the lines blur … a lot. If you’re a back end developer working for a fairly small company, you will have to do a lot of this stuff. It actually makes you a much better developer, but installing a complete operating system is not just a massive pain in the arse*, but there are lots of issues you’re probably not qualified to tackle. (Security, performance, maintenance, etc.. ). The magic of yum got me a working LAMP server within about 10 minutes from a base Fedora 10 install, but I spent my weekend configuring Postfix, and Dovecot and generally ensuring the system was in reasonable shape. As usual, it took lots of Googling, forum browsing, and chatting to the excellent Slicehost support people – This is not what I do for a living and I’m not particularly good at it either. I build web apps, and I need to remember that.

* UK Glossary: arse = ass

• I will arrive early at your office. Nobody is there to let me in, but I’m still “on site”, so I’m still leaving at 4:30;
• If you ask me to come in a bit later the following day, I will arrive an additional hour late just to be sure, or possibly to teach you a lesson;
• When we discuss the project, I will use words you don’t understand. When you ask me to clarify, I’ll just repeat the same words again, until you get embarrassed enough to stop asking;
• The less you understand about my job, the less respect I will give you, and the less helpful I will be;
• If you aren’t running the right software, God help you! I did say – briefly over the phone a few weeks ago, possibly;
• If you had recently hired another developer, I will be sure to slag off their work and give you totally different information than you got from them;
• If the previous developer was from another country I will make racist slurs assuming that you are probably as comfortable with that as I am;
• I’ll decide when the job is finished. You can disagree, but I’ll do my best to intimidate you into saying everything is fine so I can get to the pub;
• You will pay me in cash as I am walking out the door on my last day. No 30 day nonsense. And I may not have an invoice “on me”, but I’ll promise to drop one in sometime;
• If the project takes longer, or is more difficult than expected, I will not work late – you’ll just have to wait!

I am now late for work. Sans builder. But I’m sure it will be fine when I get home at 8pm.