CfScript

CfScript is a DSL for scripting the Cloud Foundry CLI, with a focus on application deployment and management. See Supported Commands

# example.rb
require 'cf_script'

cf space: :development do
  workers = apps ending_with: 'worker'

  workers.each do |worker|
    app worker do
      show :state, :memory, :instances

      stop if started?

      progress 'Setting ENV variable...'
      set_env 'SOME_NAME', 'SOME_VALUE'

      progress "Restaging #{name} in #{current_space}..."
      restage
    end
  end
end

To see the cf commands that get executed, run with TRACE=1.

TRACE=1 ruby example.rb

• ruby >= 2.2
• cf >= 6.0

Install the gem with:

gem install cf_script

Or, add it to your project's Gemfile:

gem 'cf_script'

There are three execution scopes/blocks; cf, space, and app:

The cf scope is the top-level scope, it includes evertything between the do/end following a call to cf. The scope saves the current target on entry and restores it on exit.

# cf target => staging

cf space: :development do
	# cf target => development
end

# cf target => staging

The cf block accepts the following options:

• api: Sets the API endpoint (optional)
• org: Sets the target organization (optional)
• username/password: Credentials to use for logging in. (optional)
• space: Sets the target space (optional)

Note: To save the current target the cf block will execute cf target on entry, and if it changed within the block, it wil execute cf target SPACE on exit to restore it.

The space scope is a sub-scope and can only appear within a cf block. It also saves the current target on entry and restores, if changed, it on exit.

# before cf block, target => staging

cf space: :development do
  # inside cf block, target => development

  space :production do
    # inside space block, target => production
  end

  # still inside cf block, target => development
end

# after cf block, target => staging

The app scope can appear within a cf or space blocks. Within the block the selected app is the target of commands, this means that commands that take an application name as their first argument can be called without it.

cf do
  app :api do
    env.each do |name, value|
      unset_env name
    end

    started? ? restart : start
  end
end

The app method accepts a string or an AppInfo object as a name argument.

The apps method mirrors the cf apps command. When called without a block, it returns an AppList object that acts as an array of AppInfo objects, each of which contains the information in each row output by cf apps.

cf do
  # Get the list of AppInfo objects
  space_apps = apps

  # Iterate over the AppInfo objects
  apps.each do |app_info|
    # ...
  end
end

When the apps method is called with a block, it excutes the block within the context of each app.

cf do
  apps do
    started? ? restart : start
  end
end

This is equivalent to:

cf do
  apps.each do |app_info|
    app app_info do
      started? ? restart : start
    end
  end
end

The project uses the standard rubygems package tasks, so:

To build your cloned copy of the gem, run:

rake build

To install the gem from the cloned project, run:

rake install

• Obviously everything depends on the output of cf, so if that changes things will break. This is not unique to cf_script, but it is something worth noting. The centralized parsing of cf's output should reduce the impact of change on scripts, but there is no guarantee.

• The fixtures were collected manually and they might become a pain to manage. Will investigate creating a tool/script that automates their collection from cf.

• I18N, n'existe pas, mais, it's not impossible. If implemented, it should be based on the latest translation files from the cf repository, and the process of pulling the files automated. In the meantime, might explicity add LANG to the ENV variables passed to cf.

• Windows? No clues. Probably not without some changes.