Capistrano "push strategy", revisited

file.rb

## Capistrano "push strategy", take 2
# 
# It's based on "remote_cache", but doesn't rely on a central git repository.
# It assumes that the code is already pushed to its "cached-copy".
# 
# Usage:
# 
#   git remote add origin example.com:/path/to/my-app/shared/cached-copy/.git
#   cap deploy
# 
# (If you want to call the remote something other than "origin", remember to
# tweak the "remote" setting in the recipe below.)


# set up these:
set :application, "my-app"
set :use_sudo,    false

# tweak the following if you wish:
set :remote, 'origin'
set :branch, 'master'
set :git_enable_submodules, true

# deduces the deploy host and directory from your push target
remote_host, remote_path = `git config remote.#{remote}.url`.chomp.split(':', 2)

set :deploy_to, remote_path.split('/shared/cached-copy/').first
server remote_host, :app, :web, :db, :primary => true

# DON'T change these:
set :repository,  ".git"
set :scm,         :git
set :deploy_via,  :remote_cache
set(:source)      { GitLocal.new(self) }

# hook to automatically push code before every deploy
before 'deploy:update_code' do
  puts "Pushing #{branch} code to git repository ..."
  system "git push #{remote} #{branch}"
  abort unless $?.success?
end

#===============================#
# Rest of your recipe goes here #
#===============================#


# at the end, a little magic to make it all happen
require 'capistrano/recipes/deploy/scm/git'

class GitLocal < ::Capistrano::Deploy::SCM::Git
  default_command "git"
  
  def checkout(revision, destination)
    %(echo 'ABORTED: you must first initialize the git repository in "#{destination}"' && exit 1)
  end
  
  def sync(revision, destination)
    git     = command
    execute = ["cd #{destination}"]

    # since we're in a local branch already, just reset to specified revision rather than merge
    execute << "#{git} reset --hard #{revision}"

    if configuration[:git_enable_submodules]
      execute << "#{git} submodule #{verbose} init"
      execute << "#{git} submodule #{verbose} update"
    end

    execute.join(" && ")
  end
end