What Is This?
Unicorn is a fast HTTP web server written in Ruby, able to run Rack and Rails apps.
To run this code on DotCloud, you need to get a DotCloud account. DotCloud has a free tier, so you won't even need to draw your wallet!
Then clone this repository:
$ git clone git://github.com/caleywoods/quadricorn.git
And push it to DotCloud:
$ cd quadricorn $ dotcloud push unicorn
Happy hacking! Remember: each time you modify something, you need to
git add + git commit your changes before doing
How Does It Work?
Since DotCloud cannot run arbitrary web servers (yet!), we use a ruby service (which uses the nginx web server to handle HTTP requests). Inside this service, we setup Unicorn to run on port 8080 (default). Then, we add an nginx configuration snippet to proxy all incoming HTTP requests to port 8080, effectively routing them to Unicorn, instead of Passenger.
To streamline scaling and deployment, we use a Gemfile (to install the unicorn gem automatically), as well as the god process manager (to start unicorn automatically).
If you want to see how this sample app was built, we invite you to:
- see the big picture with GitHub's awesome compare view -- click on each individual commit to see detailed explanations for each step
- if you prefer text mode (or offline inspection), fallback on
git log --patch --reverse
- dive into DotCloud documentation, especially the one for the Ruby service which is used by this app.
Is This A Hack?
Yes, in the positive acceptance of this word :-)
Is This Supported?
Not officially. However, since it uses only documented parts of DotCloud (ruby service, postinstall script, nginx snippet...), there's a high likelihood it will still work with future versions of DotCloud.
As a matter of fact, when DotCloud releases better support for Unicorn and other evented web servers, the modifications required to update your code will be very, very minor.