How to version my rails application

Step 1

Create your app/.version file.

app/.version

1.0.1

Step 2

Create a rake task that reads that version and generates some ruby code that blends into your rails app.

app/lib/tasks/create_version.rake

task :create_version do
  desc "Create version"
  version = File.read("#{Rails.root}/.version").split('.')
  version_file = "#{Rails.root}/config/initializers/version.rb"

  major = version[0]
  minor = version[1]
  patch = version[2]
  build = `git describe --always --tags`

  version_string = "module App
  class Application < Rails::Application
    VERSION = \"#{major.to_s}.#{minor.to_s}.#{patch.to_s}.#{build.strip}\"
  end
end"

  File.open(version_file, "w") {|f| f.print(version_string)}
end

Step 3

Run the rake task accordingly to your deploy pipeline or manually but make sure you always commit it.

Step 4

Check the generated file.

app/config/initializers/version.rb

module App
  class Application < Rails::Application
    VERSION = "1.0.1.887f65e"
  end
end

Step 5

Inlcude your generated version initializer into the main application.rb config file.

app/config/application.rb

...
require_relative "initializers/version"
...

Step 6

Print it wherever you need it, in the views or maybe in a controller.

My version: <%= App::Application::VERSION %>