vagrant/plugins/providers/docker/action/build.rb

require "log4r"

require "vagrant/util/ansi_escape_code_remover"

module VagrantPlugins
  module DockerProvider
    module Action
      class Build
        include Vagrant::Util::ANSIEscapeCodeRemover

        def initialize(app, env)
          @app = app
          @logger = Log4r::Logger.new("vagrant::docker::build")
        end

        def call(env)
          machine   = env[:machine]
          build_dir = env[:build_dir]
          build_dir ||= machine.provider_config.build_dir
          git_repo  = env[:git_repo]
          git_repo  ||= machine.provider_config.git_repo
          
          # If we're not building a container, then just skip this step
          return @app.call(env) if (!build_dir && !git_repo)

          # Try to read the image ID from the cache file if we've
          # already built it.
          image_file = machine.data_dir.join("docker_build_image")
          image      = nil
          if image_file.file?
            image = image_file.read.chomp
          end

          # Verify the image exists if we have one
          if image && !machine.provider.driver.image?(image)
            machine.ui.output(I18n.t("docker_provider.build_image_invalid"))
            image = nil
          end

          # If we have no image or we're rebuilding, we rebuild
          if !image || env[:build_rebuild]
            # Build it
            args = machine.provider_config.build_args.clone
            if machine.provider_config.dockerfile
              dockerfile      = machine.provider_config.dockerfile
              dockerfile_path = File.join(build_dir, dockerfile)

              args.push("--file").push(dockerfile_path)
              machine.ui.output(
                I18n.t("docker_provider.building_named_dockerfile",
                file: machine.provider_config.dockerfile))
            else
              machine.ui.output(I18n.t("docker_provider.building"))
            end

            image = machine.provider.driver.build(
              build_dir || git_repo,
              extra_args: args) do |type, data|
              data = remove_ansi_escape_codes(data.chomp).chomp
              env[:ui].detail(data) if data != ""
            end

            # Output the final image
            machine.ui.detail("\nImage: #{image}")

            # Store the image ID
            image_file.open("w") do |f|
              f.binmode
              f.write("#{image}\n")
            end
          else
            machine.ui.output(I18n.t("docker_provider.already_built"))
          end

          # Set the image for creation
          env[:create_image] = image

          @app.call(env)
        end
      end
    end
  end
end