Building Small Web Services with a Heroku and Unicorn Sinatra Template Project

Blog.creole

Using Sinatra Unicorn and Heroku (CEDAR stack) Together!

I have been asked

• "How do I get started with Unicorn and Heroku?"
• "How can I made a remote HTTP webhook?"
• "How can I make a simple web service?" ,
• "How can I get started with a free ruby hosting evironment?"

I want to take a moment to answer a few of these questions in a small package I have extracted from one of our small services. This package is avalible on https://github.com/blazingcloud/sinatra-with-unicorn with a MIT License

This blog posts assumes basic familiarity with the 'git' command : http://gitimmersion.com/

• '$' will prefix every command example:

$ echo "<3"

Follow these steps to get started :

1. Login or create a github.com account
2. Visit https://github.com/blazingcloud/sinatra-with-unicorn in your web browser and 'FORK' the repository.
3. Rename your fork by clicking the 'ADMIN' button

• I gave mine a name off the top of my head : monkey-flyer-radio-protocol-death-claw-alpha

Follow these steps to set-up development:

I will follow each of the steps with the command that I used - replace 'monkey-flyer-radio-protocol-death-claw-alpha' with your project fork name

• clone your repository

$ git clone git@github.com:robotarmy/monkey-flyer-radio-protocol-death-claw-alpha.git

• The repository has been setup to use bundler with a Gemfile - you will need to install bundler

$ gem install bundler

• With bundler installed you can use the Gemfile to manage installation of gems :

$ bundle

Follow these steps to change the default GET uri '/' and see the results

• open ./modules/site/main.erb in your editor
  • you can put html in here or text
• run the server

$ foreman start 

• open the browser up to http://localhost:5000
  • see it works!

• Use 'CTRL-C' to stop the server

Follow these steps to add a post uri '/deathclaw' and see the results

• open ./modules/site.rb in your editor
  • this is a Sinatra Module - it has a get '/' defined already.
• add a line of code in the body of the class after the 'get' part

  post "/deathclaw" do
      """
      Name
      Deathclaw alpha male

      ID
      00167ec1

      Level
      25

      Experience points
      50

      Perception
      8

      Hit points
      750

      Damage Threshold
      15

      Damage Resistance
      0%


      Aggression
      Confidence
      Assistance

      Melee (300 Damage)
          dead 15% Deathclaw egg
          dead 35% Deathclaw hand

   """
  end

• run your service again

$ foreman start

• run a post with curl on the command line in a new console window

$ curl -d var=1 http://localhost:5000/deathclaw

Check in your changes

$ git add .

$ git commit -m 'I made a post /deathclaw'

Release to Heroku (ON CEDAR STACK)

• create a new heroku app ( i named mine )

 $ heroku create radio-protocol-death-claw --stack cedar 

• release your code to heroku ( heroku creates a git remote 'heroku' )
  • you should see messages about heroku recieving your push and installing your gems via bundler

 $ git push heroku master

• check your get

curl http://radio-protocol-death-claw.herokuapp.com/

• check your post

curl -d var=1 http://radio-protocol-death-claw.herokuapp.com/deathclaw

DEBUGGING HELP

• foreman start
  • this command will not reload your code changes - you will need to use 'rerun' if you want that.
  • rails does this for free - at the cost of increased learning curve

• curl ARGS URL
  • no args
    • does a get
  • -d var=1
    • this tells curl to do a post with a post variable (unused, but simulates a post)