#492—

Sinatra, Heroku and You

By Nat Welch

So there I was, done with finals, a fresh Mocha, a large piece of coffee cake and a quiet café with a fast wireless internet connection. What should I do? Ah ha! Code!

I have, for a while, been looking for a good place to store my thoughts. I didn't need a to-do list, because most of the stuff I write down is more of a "wouldn't this be cool" instead of a "you need to do this in the next two days".

A long time ago I had started a little PHP app called theStack to do just this. I sadly though abandoned it due to time constraints. On this day with nothing but free time, I decided to code it up. I took a quick look at the PHP, and said, "the hell with this, I'm going to be trendy and code this in ruby."

The first thing I needed was to figure out how to code ruby for the web. I had heard rails was awesome, but I also heard that it had a ton of overhead. Then I remembered Sinatra. Sinatra is a nice, small, and easy web framework that is really easy to learn. I read through the readme and started coding.

The readme is misleading. One thing it does not mention is that all of its code is for Sinatra >= 1.0, which, until recently, the ruby gem did not install by default. Also, since I had planned on deploying this to Heroku, I needed to figure out how to get Heroku using the correct version of Sinatra (Heroku, by default, uses 0.9.4).

To install the correct version of Sinatra on your local machine is quite easy now that 1.0 has been released, but if for some reason you are trying to get the delopment build instead of the stable build, you can add --pre to the gem install:

gem install --pre sinatra

The main two things that 1.0 support adds, is support for less and erubis.

Less

My friend Reed introduced me to less a little while ago. It's very similar to CSS, but allows for you to nest things, and save information into variables, which is pretty awesome, and generally makes CSS files easier to read and code.

Erubis

Since I started writing this article, I've actually given up on erubis. It's meant to be a fast version of ERB, but it has a decent amount of bugs in it, so I switched to plain ERB, and have been loving every minute of it.

Gems on Heroku

To get gems (such as Sinatra and less) on Heroku, you need a .gems file in your git repository. I have provided an example, but it is pretty straight forward.

less erubis sinatra --version 1.0 rdiscount sequel sqlite3-ruby

Coding...

I think I'll save this for a sperate article, but you can see the code I am writing on GitHub.

Deploying.

Deploying to Heroku is pretty easy. You can use two methods, either a Rakefile, or just from the straight command line.

First you need to create an account on Heroku and then follow their quickstart guide. But the general overview is pretty simple. First gem install heroku then run heroku create in your directory. Finally run git push heroku master. Now your app is running on heroku! Also before you start, you need to have a git repository for your project, which I assume you know how to do.

You can also add the following to your Rakefile, so you would type rake deploy instead of git push heroku master.

desc "Deploy to Heroku."
task :deploy do
   require 'heroku'
   require 'heroku/command'
   user, pass = File.read(File.expand_path("~/.heroku/credentials")).split("\n")
   heroku = Heroku::Client.new(user, pass)

   cmd = Heroku::Command::BaseWithApp.new([])
   remotes = cmd.git_remotes(File.dirname(__FILE__) + "/../..")

   remote, app = remotes.detect {|key, value| value == (ENV['APP'] || cmd.app)}

   if remote.nil?
   raise "Could not find a git remote for the '#{ENV['APP']}' app"
   end

   `git push #{remote} master`

   heroku.restart(app)
end

Anyway, I kind of rushed this, because I wrote most of the post about a month ago and then forgot about it. Once I am happy with theStack, I'll write another post here about coding with Sinatra, ERB, less, Sequel, and Heroku.

Hasta,
/Nat

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#493