Capistrano Custom SCM

README.md

Capistrano Custom SCM

Overview

Capistrano 3.7.0 and newer has three SCM plugins (Git/Subversion/Mercurial).

• http://capistranorb.com/documentation/advanced-features/custom-scm/

As the link above shows, it is also possible to provide a custom SCM plugin. The implementations of the default plugins would help you know the nuts and bolts.

Capistrano::SCM::Tgz

# .tgz file to be extracted into releases (required)
set :tgz_archive, "path/to/archive.tar.gz"
#set :tgz_archive, ask("Enter the path to *.tar.gz")

# tar --strip-components option (default: 0)
set :tgz_strip_components, 0

capistrano-scm-tgz.rb

require "capistrano/scm/plugin"
require "digest/sha1"

class Capistrano::SCM::Tgz < Capistrano::SCM::Plugin

  def set_defaults
  end

  def register_hooks
    after "deploy:new_release_path", "tgz:create_release"
    before "deploy:set_current_revision", "tgz:set_current_revision"
  end

  def define_tasks
    this_plugin = self

    namespace :tgz do

      desc "Extract .tgz archive to releases"
      task :create_release do

        tgz_archive = this_plugin.as_tgz_archive(fetch(:tgz_archive))
        n = fetch(:tgz_strip_components, 0)

        on release_roles :all do
          execute :mkdir, "-p", release_path
          tmp_file = capture("mktemp")
          upload!(tgz_archive, tmp_file)
          execute :tar, "--strip-components=#{n}", "-xzf", tmp_file, "-C", release_path
          execute :rm, tmp_file
        end
      end

      task :set_current_revision do
        tgz_archive = this_plugin.as_tgz_archive(fetch(:tgz_archive))
        set :current_revision, Digest::SHA1.file(tgz_archive).hexdigest 
      end
    end
  end

  def as_tgz_archive(path)
    raise ":tgz_archive is not a regular file." unless File.exists? path
    path
  end
end