My micro-talk to the Grand Rapids Ruby Group on separating code and configuration.

gistfile1.txt

            /$$$$$$   /$$$$$$  /$$   /$$ /$$$$$$$$ /$$$$$$  /$$$$$$
           /$$__  $$ /$$__  $$| $$$ | $$| $$_____/|_  $$_/ /$$__  $$
          | $$  \__/| $$  \ $$| $$$$| $$| $$        | $$  | $$  \__/
          | $$      | $$  | $$| $$ $$ $$| $$$$$     | $$  | $$ /$$$$
          | $$      | $$  | $$| $$  $$$$| $$__/     | $$  | $$|_  $$
          | $$    $$| $$  | $$| $$\  $$$| $$        | $$  | $$  \ $$
          |  $$$$$$/|  $$$$$$/| $$ \  $$| $$       /$$$$$$|  $$$$$$/
           \______/  \______/ |__/  \__/|__/      |______/ \______/

                 /$$                                       /$$
                |__/                                      | $$
                 /$$  /$$$$$$$       /$$$$$$$   /$$$$$$  /$$$$$$
                | $$ /$$_____/      | $$__  $$ /$$__  $$|_  $$_/
                | $$|  $$$$$$       | $$  \ $$| $$  \ $$  | $$
                | $$ \____  $$      | $$  | $$| $$  | $$  | $$ /$$
                | $$ /$$$$$$$/      | $$  | $$|  $$$$$$/  |  $$$$/
                |__/|_______/       |__/  |__/ \______/    \___/

                  /$$$$$$   /$$$$$$  /$$$$$$$  /$$$$$$$$
                 /$$__  $$ /$$__  $$| $$__  $$| $$_____/
                | $$  \__/| $$  \ $$| $$  \ $$| $$
                | $$      | $$  | $$| $$  | $$| $$$$$
                | $$      | $$  | $$| $$  | $$| $$__/
                | $$    $$| $$  | $$| $$  | $$| $$
                |  $$$$$$/|  $$$$$$/| $$$$$$$/| $$$$$$$$
                 \______/  \______/ |_______/ |________/


                    Presented with ♥ by @bkeepers


###############################################################################
# Config should be separate from code
###############################################################################






    Environments don't scale cleanly:


      development, staging, production,
      qa, labs, joes-laptop, joes-staging, joes-ec2-dev







    Config varies substantially across deploys, code does not.








    The Twelve-Factor App
    http://12factor.net/config
    The twelve-factor app stores config in environment variables







    ⚛ ⚛ ⚛ ⚛ ⚛ ⚛ ⚛ ⚛ ⚛ ⚛ ⚛ ⚛ ⚛ ⚛ ⚛ ⚛ Litmus Test ⚛ ⚛ ⚛ ⚛ ⚛ ⚛ ⚛ ⚛ ⚛ ⚛ ⚛ ⚛ ⚛ ⚛ ⚛ ⚛

                Can the codebase be made open source at any moment,
                without compromising any credentials?

    ⚛ ⚛ ⚛ ⚛ ⚛ ⚛ ⚛ ⚛ ⚛ ⚛ ⚛ ⚛ ⚛ ⚛ ⚛ ⚛ ⚛ ⚛ ⚛ ⚛ ⚛ ⚛ ⚛ ⚛ ⚛ ⚛ ⚛ ⚛ ⚛ ⚛ ⚛ ⚛ ⚛ ⚛ ⚛ ⚛ ⚛ ⚛









☼☼☼☼☼☼☼☼☼☼☼☼☼☼☼☼☼☼☼☼☼☼☼☼☼☼☼☼☼☼☼☼☼☼☼☼☼☼☼☼☼☼☼☼☼☼☼☼☼☼☼☼
☼
☼    What is NOT configuration?
☼
☼☼☼☼☼☼☼☼☼☼☼☼☼☼☼☼☼☼☼☼☼☼☼☼☼☼☼☼☼☼☼☼☼☼☼☼☼☼☼☼☼☼☼☼☼☼☼☼☼☼☼☼

* internal application config (conig/routes.rb)


Things that don't change between deployments.









☂☁☂☁☂☁☂☁☂☁☂☁☂☁☂☁☂☁☂☁☂☁☂☁☂☁☂☁☂☁☂☁☂☁☂☁☂☁☂☁☂☁☂☁☂☁☂
☁
☂    What is configuration?
☁
☂☁☂☁☂☁☂☁☂☁☂☁☂☁☂☁☂☁☂☁☂☁☂☁☂☁☂☁☂☁☂☁☂☁☂☁☂☁☂☁☂☁☂☁☂☁☂


1. Resource handles to data stores (database, memcached)

2. Credentials to external services (Amazon S3 or Twitter)

3. Per-deploy values such as the canonical hostname for the deploy



Anything that needs changed to deploy a new instance of the application








     _             _ _
    | |           ( ) |    _
  __| | ___  _ __ |/| |_  (_)
 / _` |/ _ \| '_ \  | __|
| (_| | (_) | | | | | |_   _
 \__,_|\___/|_| |_|  \__| (_)


    <% if Rails.env.production? %>
      Google Analytics code with hard-coded ID
    <% end %>



     _
    | |        _
  __| | ___   (_)
 / _` |/ _ \
| (_| | (_) |  _
 \__,_|\___/  (_)


    <% if ENV['GOOGLE_ANALYTICS_ID'] %>
      Google Analytics code with dynamic <%= ENV['GOOGLE_ANALYTICS_ID'] %>
    <% end %>







    # config/initializers/secret_token.rb

    Rails.application.config.secret_key_base = ENV['SECRET_KEY_BASE']





    # config/initializers/carrierwave.rb

    CarrierWave.configure do |config|
      config.fog_credentials = {
        :provider               => 'AWS',
        :aws_access_key_id      => ENV['S3_ACCESS_KEY'],
        :aws_secret_access_key  => ENV['S3_SECRET_ACCESS_KEY']
      }

      config.fog_directory  = ENV['S3_BUCKET']
    end









                                   ,.--.
                                  //    \
                                  \\    /
                                   `'--'

                                   ,.--.
                                  //    \
                                  \\    /
                                   `'--'

                                   ,.--.
                                  //    \
                                  \\    /
                                   `'--'

                                   ,.--.
                                  //    \
                                  \\    /
                                   `'--'

                                   ,.--.
                                  //    \
                                  \\    /
                                   `'--'

                                   ,.--.
                                  //    \
                                  \\    /
                                   `'--'


                  888            d8
             e88~\888  e88~-_  _d88__  e88~~8e  888-~88e Y88b    /
            d888  888 d888   i  888   d888  88b 888  888  Y88b  /
            8888  888 8888   |  888   8888__888 888  888   Y88b/
            Y888  888 Y888   '  888   Y888    , 888  888    Y8/
             "88_/888  "88_-~   "88_/  "88___/  888  888     Y


                    https://github.com/bkeepers/dotenv




    gem 'dotenv-rails'













###############################################################################
# Example .env file from the project I work on every day
###############################################################################

APP_HOST=talks.dev
APP_PROTOCOL=http
FAILBOT_BACKEND=memory
GITHUB_APP_KEY=[redacted]
GITHUB_APP_SECRET=[redacted]
INSTRUMENTAL_API_KEY=[redacted]
MAILGUN_DOMAIN=localhost
S3_ACCESS_KEY=[redacted]
S3_SECRET_ACCESS_KEY=[redacted]
S3_BUCKET=github-talks-dev
ZENCODER_API_KEY=[redacted]
# Tell Resque to properly handle unix signals
TERM_CHILD=1
QUEUE=users,mailer,talks,search,*

# Use local file uploads instead of S3
# S3_UPLOADS=false

# Use github.dev instead of github.com
# LOCAL_GITHUB=true

# These variables should also be defined in production
# IMAGE_PROXY_URL
# GAUGES_ID
# GOOGLE_ANALYTICS_ID

###############################################################################










     _            _                                  _  ___
    | |          | |                                | ||__ \
  __| | ___ _ __ | | ___  _   _ _ __ ___   ___ _ __ | |_  ) |
 / _` |/ _ \ '_ \| |/ _ \| | | | '_ ` _ \ / _ \ '_ \| __|/ /
| (_| |  __/ |_) | | (_) | |_| | | | | | |  __/ | | | |_|_|
 \__,_|\___| .__/|_|\___/ \__, |_| |_| |_|\___|_| |_|\__(_)
           | |             __/ |
           |_|            |___/