1-suggestion.md

When building highly decoupled classes I often run into the problem of how to piece it all together. I have an understanding of how each piece is supposed to interact but I'm not sure how the functionality should co-exist. I have included some sample code below.

2-code.rb

class Project
  attr_accessor :name
end

class Deploy
  def initialize options = {}
    @branch = options.fetch(:branch, 'master')
    @cli    = options.fetch(:cli, Capistrano::CLI)
  end

  def run
    @cli.parse(args).execute
  end
end

class Repo
  def initialize project, vendor_path = Rails.root.join('vendor', 'repos')
    @project     = project
    @vendor_path = vendor_path
  end

  def path
    @vendor_path.join project.name
  end

  def pull
    git.pull
  end

  private

  def git
    @git ||= Grit::Git.new path
  end
  attr_writer :git
end

class DeployPreparation
  def initialize repo
    @repo = repo
  end

  def prepare
    Dir.chdir @repo.path
    @repo.pull
  end
end

3-suggestion-cont.md

So now I have these highly decoupled classes but I am at a loss which is the best way to invoke this functionality. My immediate guess is create a helper method on Project that exposes what I'm after:

class Project
  # ...

  def deploy options
    options ||= {}

    repo = Repo.new self
    DeployPreparation.new(repo).prepare
    Deploy.new(options).run
  end
end

Or should I bundle up all this functionality into another class? It would be nice to be able to invoke 1 method and have a deployment run. A side benefit of bundling it up into another class would be that I could tie in backgrounding the entire process without effecting each individual part:

class DeployCoordinator
  def initialize project, options
    @project = project
    @options = options
  end

  def deploy
    DeployPreparation.new(repo).prepare
    Deploy.new(options).run
  end
  alias :perform :deploy

  def repo
    repo = Repo.new @project
  end
end

class Project
  # ...

  def deploy options
    options ||= {}
    DeployCoordinator.new(project, options).deploy
  end
end

I guess it really comes down to what feels best to you as a developer, but I often find myself not knowing which is the best approach.