Bundle Git deployer

lib/nanoc/deploying/deployers.rb

@@ -2,9 +2,11 @@ module Nanoc::Deploying
   # @api private
   module Deployers
     autoload 'Fog',   'nanoc/deploying/deployers/fog'
+    autoload 'Git',   'nanoc/deploying/deployers/git'
     autoload 'Rsync', 'nanoc/deploying/deployers/rsync'
 
     Nanoc::Deploying::Deployer.register '::Nanoc::Deploying::Deployers::Fog',   :fog
+    Nanoc::Deploying::Deployer.register '::Nanoc::Deploying::Deployers::Git',   :git
     Nanoc::Deploying::Deployer.register '::Nanoc::Deploying::Deployers::Rsync', :rsync
   end
 end

lib/nanoc/deploying/deployers/git.rb

@@ -0,0 +1,119 @@
+module Nanoc::Deploying::Deployers
+  # A deployer that deploys a site using [Git](http://git-scm.com).
+  #
+  # @example A deployment configuration for GitHub Pages:
+  #
+  #   deploy:
+  #     default:
+  #       kind:       git
+  #       remote:     git@github.com:myself/myproject.git
+  #       branch:     gh-pages
+  #       forced:     true
+  #
+  class Git < ::Nanoc::Extra::Deployer
+    identifier :git
+
+    module Errors
+      class Generic < ::Nanoc::Error
+      end
+
+      class OutputDirDoesNotExist < Generic
+        def initialize(path)
+          super("The directory to deploy, #{path}, does not exist.")
+        end
+      end
+
+      class OutputDirIsNotAGitRepo < Generic
+        def initialize(path)
+          super("The directory to deploy, #{path}, is not a Git repository.")
+        end
+      end
+
+      class RemoteDoesNotExist < Generic
+        def initialize(remote)
+          super("The remote to deploy to, #{remote}, does not exist.")
+        end
+      end
+
+      class BranchDoesNotExist < Generic
+        def initialize(branch)
+          super("The branch to deploy, #{branch}, does not exist.")
+        end
+      end
+    end
+
+    # @see Nanoc::Extra::Deployer#run
+    def run
+      unless File.exist?(source_path)
+        raise Errors::OutputDirDoesNotExist.new(source_path)
+      end
+
+      remote = config.fetch(:remote, 'origin')
+      branch = config.fetch(:branch, 'master')
+      forced = config.fetch(:forced, false)
+
+      puts "Deploying via git to remote='#{remote}' and branch='#{branch}'"
+
+      Dir.chdir(source_path) do
+        unless File.exist?('.git')
+          raise Errors::OutputDirIsNotAGitRepo.new(source_path)
+        end
+
+        # Verify existence of remote, if remote is not a URL
+        if remote_is_name?(remote)
+          begin
+            run_cmd(%W(git config --get remote.#{remote}.url))
+          rescue Nanoc::Extra::Piper::Error
+            raise Errors::RemoteDoesNotExist.new(remote)
+          end
+        end
+
+        # If the branch exists then switch to it, otherwise prompt the user to create one.
+        begin
+          run_cmd_unless_dry(%W(git checkout #{branch}))
+        rescue Nanoc::Extra::Piper::Error
+          raise Errors::BranchDoesNotExist.new(branch)
+        end
+
+        return if clean_repo?
+
+        msg = "Automated commit at #{Time.now.utc} by Nanoc #{Nanoc::VERSION}"
+        author = 'Nanoc <>'
+        run_cmd_unless_dry(%w(git add -A))
+        run_cmd_unless_dry(%W(git commit -a --author #{author} -m #{msg}))
+
+        if forced
+          run_cmd_unless_dry(%W(git push -f #{remote} #{branch}))
+        else
+          run_cmd_unless_dry(%W(git push #{remote} #{branch}))
+        end
+      end
+    end
+
+    private
+
+    def remote_is_name?(remote)
+      remote !~ /:\/\/|@.+:/
+    end
+
+    def run_cmd(cmd)
+      piper = Nanoc::Extra::Piper.new(stdout: $stdout, stderr: $stderr)
+      piper.run(cmd, nil)
+    end
+
+    def run_cmd_unless_dry(cmd)
+      if dry_run
+        puts cmd.join(' ')
+      else
+        run_cmd(cmd)
+      end
+    end
+
+    def clean_repo?
+      stdout = StringIO.new
+      piper = Nanoc::Extra::Piper.new(stdout: stdout, stderr: $stderr)
+      piper.run(%w(git status --porcelain), nil)
+      stdout.string.empty?
+    end
+  end
+end

spec/nanoc/cli/commands/deploy_spec.rb

@@ -75,7 +75,7 @@
         let(:run) { Nanoc::CLI.run(command) }
 
         it 'lists all deployers' do
-          expect { run }.to output(/Available deployers:\n  fog\n  rsync/).to_stdout
+          expect { run }.to output(/Available deployers:\n  fog\n  git\n  rsync/).to_stdout
         end
 
         include_examples 'no effective deploy'