task restart passenger

#simple rake task to restart passenger
# paste into lib/tasks/server.rb
namespace :server do

  desc 'Deplying to server'
  task deploy: :environment do

    asset_precompilation_triggers = %w(app/assets vendor/assets Gemfile.lock config)

    if (deployed_file_exists?("db/schema.rb") || deployed_file_exists?("db/structure.sql")) && trigger_update?("db/")
      puts "post_deploy: migrating..."
      system "bundle exec rake db:migrate 2>&1"
    end

    if asset_precompilation_triggers.detect {|path| trigger_update?(path)}
      puts "post_deploy: assets:precompile..."
      system "bundle exec rake assets:precompile 2>&1"
    end

    system "bundle exec rake server:restart 2>&1"

    save_commit_count
  end

  desc 'Restarting server'
  task restart: :environment do
    puts 'Restarting...'
    unless File.directory?('tmp')
      system 'mkdir tmp'
    end
    system "touch tmp/restart.txt 2>&1"
  end


  def deploy_to
    "."
  end


  # Capture the result of a git command run within the `deploy_to` directory
  def capture_git(command)
    `cd #{deploy_to} && git #{command}`
  end

  def trigger_update?(path)
    # puts "updated? #{path} in #{changed_files.inspect}"
    changed_files.detect {|p| p[0, path.length] == path}
  end

  def changed_files
    # puts "latest tag: #{latest_tag}"
    cnt = latest_merge_count
    # puts "commit since last push: #{cnt}"
    @changed_files = capture_git('diff --name-only HEAD~'+cnt.to_s+' | cat').split
    # @changed_files ||= if latest_tag
    #   capture_git("diff --name-only #{latest_tag} origin/#{branch} | cat").split
    # else
    #   capture_git("ls-files | cat").split
    # end
  end

  def deployed_file_exists?(path)
    exit_code("cd #{deploy_to} && [ -f #{path} ]") == "0"
  end

  # Does the given directory exist within the deployment directory?
  def deployed_dir_exists?(path)
    exit_code("cd #{deploy_to} && [ -d #{path} ]") == "0"
  end

  # Has the given path been created or changed since the previous deployment?  During the first
  # successful deployment this will always return true if the file exists.
  def deployed_file_changed?(path)
    return deployed_file_exists?(path) unless latest_tag
    exit_code("cd #{deploy_to} && git diff --exit-code #{latest_tag} origin/#{branch} #{path}") == "1"
  end

  def exit_code(command)
    # puts "cmd: #{command} > /dev/null 2>&1; echo $?".strip
    # Ammeter.OutputCapturer.capture("#{command} > /dev/null 2>&1; echo $?").strip
    `#{command} > /dev/null 2>&1; echo $?`.strip
  end

  def latest_merge_count
    if File.exists?("../shared/git_count")
      res = `cat ../shared/git_count`.strip.to_i
      new_count = capture_git('rev-list --all --count').to_i
      return new_count - res
    else
      return 1
    end
  end

  def save_commit_count
    new_count = capture_git('rev-list --all --count').to_i
    File.open('../shared/git_count', 'w') { |file| file.write(new_count.to_s) }
  end

  def latest_tag
    latest_tag_from_repository
  end

  def release_matcher
    /\A[0-9]{14}\Z/
  end

  def latest_tag_from_repository
    tags = capture_git("tag").strip.split
    tags.grep(release_matcher).last
  end

end