A Code TV screencast on getting started with Heroku

heroku.md

Description

Heroku is a simple way to publish your Rails app, and a powerful platform that will allow it to scale. In this episode, Jay McGavren gets you started with your first Heroku app.

Set up your Rails app

Isolate your gem environment

• You WANT Rails to fail locally if a gem isn't in your Gemfile

• Otherwise you're in for a surprise when it's missing on Heroku

  $ alias be='bundle exec'

Install Postgresql

http://www.postgresql.org

Create Rails app

$ rails new chatty --database=postgresql

Set up db

$ be rake db:create

$ be rails generate scaffold Room topic:string

$ be rake db:migrate
==  CreateRooms: migrating ====================================================
-- create_table(:rooms)
NOTICE:  CREATE TABLE will create implicit sequence "rooms_id_seq" for serial column "rooms.id"
NOTICE:  CREATE TABLE / PRIMARY KEY will create implicit index "rooms_pkey" for table "rooms"
   -> 0.1256s
==  CreateRooms: migrated (0.1258s) ===========================================

Set up Git

$ git init
Initialized empty Git repository in /Users/jay/Projects/codeschool/heroku/chatty/.git/
$ git commit -am "Initial commit."

Set up Heroku

Create an account

https://api.heroku.com/signup

Download Heroku Toolbelt

https://toolbelt.herokuapp.com/

Set up Toolbelt credentials

$ heroku login
Enter your Heroku credentials.
Email: me@example.com
Password: 
Authentication successful.

Create Heroku App

$ heroku create --stack cedar
Creating gentle-river-1475... done, stack is cedar
http://gentle-river-1475.herokuapp.com/ | git@heroku.com:gentle-river-1475.git
Git remote heroku added

$ cat .git/config 
[core]
  ...
[remote "heroku"]
  url = git@heroku.com:gentle-river-1475.git
  fetch = +refs/heads/*:refs/remotes/heroku/*

$ git push heroku master

$ open http://gentle-river-1475.herokuapp.com/

Troubleshooting

Processes

$ heroku ps

Logs

$ heroku logs

Run tasks on server

$ heroku run rake db:migrate

Console

$ heroku run console

Config

Add S3 gem

gem 'aws-s3'

Embed video

<video controls width="512" height="288">
  <source 
    src="<%= AWS::S3::S3Object.url_for('demo.mp4', 'codetv-heroku1') %>"
    type="video/mp4"
  />
</video>

Don't do this!

config/initializers/s3.rb

require 'aws/s3'

AWS::S3::Base.establish_connection!(
  :access_key_id     => 'THISISSUPPOSEDTOBESECRET',
  :secret_access_key => 'DONTCOMMITTHISTOGITNOMATTERWHAT'
)

Do this!

config/initializers/s3.rb

require 'aws/s3'

AWS::S3::Base.establish_connection!(
  :access_key_id     => ENV['S3_KEY'],
  :secret_access_key => ENV['S3_SECRET']
)

Then use the toolbelt

$ heroku config:add S3_KEY=THISISSUPPOSEDTOBESECRET
$ heroku config:add S3_SECRET=DONTCOMMITTHISTOGITNOMATTERWHAT

Maintenance

Listing your apps

$ heroku apps
gentle-river-1475

Destroying an app server

$ heroku destroy gentle-river-1475

 !    WARNING: Potentially Destructive Action
 !    This command will affect the app: gentle-river-1475
 !    To proceed, type "gentle-river-1475" or re-run this command with --confirm gentle-river-1475

> gentle-river-1475

References

Heroku's Rails tutorial: https://devcenter.heroku.com/articles/rails3

Installing Postgresql: https://devcenter.heroku.com/articles/local-postgresql