At the moment I've got a light static HTML page that loads about 240Kb of Javascript and CSS (jQuery UI is big) and a couple of bytes of JSON data pulled from Node. As a little anal perfectionism I put an Nginx server in front so that Node doesn't have to serve any of the static files. To get that you have to have a Nginx site enabled that looks like this:

 server {
    root /home/peterbe/task-calendar/static;
    location / {
      if (-f $request_filename) {
          add_header X-Static hit;
          access_log   off;
      }
      if (!-f $request_filename) {
          proxy_pass http://127.0.0.1:8000; # where Node is running
          add_header X-Static miss;
      }
    }
 }

I think much of the fun of working with this app is that it's a delight to see it load in the browser without any sluggishness or delay. Lovely!

By NOT doing that, and leaving it as it is, you automatically manage to Keep It Simple Stupid and your application code makes sense to the next developer who joins your project.

I'm not a smart programmer but I'm a smart developer in that I'm good at keeping things pure and simple. It means I can't show off any fancy generators, monads or metaclasses but it does mean that fellow coders who follow my steps can more quickly hit the ground running.

My colleagues and I now have more than ten Django projects that rely on, without overriding, the django.contrib.auth.models.User class and there has been many times where I've been tempted to use it as a base class or something instead but in retrospect I'm wholeheartedly happy I didn't. The benefit isn't technical; it's a matter of teamwork and holistic productivity.

First of all a quick recap. django-static is a Django plugin that you use from your templates to reference static media. django-static takes care of giving the file the optimum name for static serving and if applicable compresses the file by trimming all whitespace and what not. For more info, see The awesomest way possible to serve your static stuff in Django with Nginx

The new, popular, kid on the block for CDN (Content Delivery Network) is Amazon Cloudfront. It's a service sitting on top of the already proven Amazon S3 service which is a cloud file storage solution. What a CDN does is that it registers a domain for your resources such that with some DNS tricks, users of this resource URL download it from the geographically nearest server. So if you live in Sweden you might download myholiday.jpg from a server in Frankfurk and if you live in North Carolina, USA you might download the very same picture from Virgina, USA. That assures the that the distance to the resource is minimized. If you're not convinced or sure about how CDNs work check out THE best practice guide for faster webpages by Steve Sounders (it's number two)

A disadvantage with Amazon Cloudfront is that it's unable to negotiate with the client to compress downlodable resources with GZIP. GZIPping a resource is considered a bigger optimization win than using CDN. So, I continue to serve my static CSS and Javascript files from my Nginx but put all the images on Amazon Cloudfront. How to do this with django-static? Easy: add this to your settings:

Then you need to write that function that get's a chance to do something with every static resource that django-static prepares. Here's a naive first version:

"Interesting article. It is saddening, however, to ponder just how much of this crowd's wealth was made through unfair business practices, worker exploitation, price fixing, etc. I suppose philanthropy on the back end is a nice afterthought, though, and certainly earns more praise from the public than would lessening their profit margins at the get-go."

"Pay their taxes first, then contribute with after tax money."

"If I may be cynical. Perhaps these super rich people should have done more for the people that worked for them so that they made more money and the leaders made a little less. Buffet owns companies that make goods in second and third world countries at some of the lowest possible wages."

"$1000 in the hands of ONE could be investment money. $1000 distributed $1 to ONE THOUSAND could get each a Coke (no fries)."

But also, there are some more "positive" comments:

"There is sooo much negativity in this country! I don't care what anyone of you says...Bill and Melinda came from Blue Collar....and now they are giving back and I think it's awesome!"

"I think what they are doing is very admirable. The Gates Foundation is the reason I was able to pay for college. People need to not criticize what they do with their money, at least they are trying to make a difference."

In conclusion from skimming the comments it's pretty obvious that people in the USA are angry and bitter. What is there to complain about? Really? Poor Obama, he's doing a great job but with all this resentment sizzling around it's going to be very hard if even "extreme philanthropy" gets butchered like this.

In lack of better imagination I decided to attack the Live Traffic Cameras data and whipped up this little app: tflcameras.peterbe.com

It basically shows a map of London and then shows all the spots where traffic cameras are installed so that you can click on them. The data is updated every 3 hours I think but I haven't checked that claim yet. Use this if you're a London commuter and want to check the traffic before you hit the road.

Oh, and this app uses the geo location stuff so that I know where to zoom in first. But if you're not based in London it zooms in over Trafalgar square by default.

I did mention to some people that one of the drawbacks of using MongoDB which doesn't have transactions is that you have to create and destroy the collections (like SQL tables) each time for every single test runs. I thought this was slow. It's not

Today I've been doing some more profiling and testing and debugging and I can conclude that it's not a problem. Creating the database has a slight delay but it's something you only have to do once and actually it's very fast. Here's how I tear down the collections in between each test:

For example, running test of one of my apps looks like this:

So, don't fear writing lots of individual unit tests. MongoDB will not slow you down.

From their help text:

"you've no doubt been subjected to the 'thread that just won't die!' If you're part of a long message conversation that isn't relevant, you can mute the conversation to keep all future additions out of your inbox."

That is such a smart feature. Interestingly I didn't even think there was a solution to that problem. I sure I have many times needed something like this. Now, let's hope I can remember to actually use this feature.

First of all, remember this? where I showed how django-mongokit sped past the SQL ORM like a lightning bullet. Well appears MongoEngine is even faster.

That's an average of 23% faster for all three operations!