Updated to be more git-friendly

This update provides the following capabilities:

* Users can now set the config boolean GIT_DESTRUCTIVE to have git
  repositories be force cleaned.
* Target git repositories are treated as git repos and not just blindly
  overwritten
* The branch name in the Puppetfile is preserved on git checkout
* The VERBOSE flag in the config file will now output the module that is
  being processed. This provides a sane verbosity between debug and
  nothing.

lib/librarian/puppet/cli.rb

@@ -48,6 +48,7 @@ def init
       option "local", :type => :boolean, :default => false
       option "use-v1-api", :type => :boolean, :default => true
       option "use-forge", :type => :boolean
+      option "git-destructive", :type => :boolean
       def install
 
         ensure!
@@ -67,6 +68,9 @@ def install
         unless options["use-forge"].nil?
           environment.config_db.local['use-forge'] = options['use-forge'].to_s
         end
+        unless options["git-destructive"].nil?
+          environment.config_db.local['git-destructive'] = options['git-destructive'].to_s
+        end
         environment.config_db.local['mode'] = options['local'] ? 'local' : nil
 
         resolve!
@@ -89,6 +93,7 @@ def update(*names)
       option "path", :type => :string
       option "destructive", :type => :boolean, :default => false
       option "use-forge", :type => :boolean
+      option "git-destructive", :type => :boolean
       def package
         environment.vendor!
         install

lib/librarian/puppet/environment.rb

@@ -61,6 +61,14 @@ def use_v1_api
       def use_forge
         config_db['use-forge'].to_s == 'false' ? false : true
       end
+
+      def git_destructive
+        config_db['git-destructive'].to_s == 'false' ? false : true
+      end
+
+      def verbose?
+        config_db['verbose'].to_s == 'false' ? false : true
+      end
     end
   end
 end

lib/librarian/puppet/source/git.rb

@@ -6,6 +6,7 @@ module Source
     class Git
       class Repository
         def hash_from(remote, reference)
+
           branch_names = remote_branch_names[remote]
           if branch_names.include?(reference)
             reference = "#{remote}/#{reference}"
@@ -14,6 +15,57 @@ def hash_from(remote, reference)
           command = %W(rev-parse #{reference}^{commit} --quiet)
           run!(command, :chdir => true).strip
         end
+
+        # Return true if the repository has local modifications, false otherwise.
+        def dirty?
+          # Ignore anything that's not a git repository
+          # This is relevant for testing scenarios
+          return false unless self.git?
+
+          status = false
+          _path = relative_path_to(path).to_s
+          begin
+            Librarian::Posix.run!(%W{git update-index -q --ignore-submodules --refresh}, :chdir => _path)
+          rescue Librarian::Posix::CommandFailure => e
+            status = "Could not update git index for '#{path}'"
+          end
+
+          unless status
+            begin
+              Librarian::Posix.run!(%W{git diff-files --quiet --ignore-submodules --}, :chdir => _path)
+            rescue Librarian::Posix::CommandFailure => e
+              status = "'#{_path}' has unstaged changes"
+            end
+          end
+
+          unless status
+            begin
+              Librarian::Posix.run!(%W{git diff-index --cached --quiet HEAD --ignore-submodules --}, :chdir => _path)
+            rescue Librarian::Posix::CommandFailure => e
+              status = "'#{_path}' has uncommitted changes"
+            end
+          end
+
+          unless status
+            begin
+              untracked_files = Librarian::Posix.run!(%W{git ls-files -o -d --exclude-standard}, :chdir => _path)
+
+              unless untracked_files.empty?
+                untracked_files.strip!
+
+                if untracked_files.lines.count > 0
+                  status = "'#{_path}' has untracked files"
+                end
+              end
+
+            rescue Librarian::Posix::CommandFailure => e
+              # We should never get here
+              raise Error, "Failure running 'git ls-files -o -d --exclude-standard' at '#{_path}'"
+            end
+          end
+
+          status
+        end
       end
     end
   end

lib/librarian/puppet/source/local.rb

@@ -9,6 +9,10 @@ module Local
         def install!(manifest)
           manifest.source == self or raise ArgumentError
 
+          if environment.verbose?
+            info { "Processing #{manifest.name}" }
+          end
+
           debug { "Installing #{manifest}" }
 
           name, version = manifest.name, manifest.version
@@ -30,12 +34,71 @@ def install!(manifest)
             install_path = environment.project_path + path.to_s
           end
 
-          if install_path.exist? && rsync? != true
-            debug { "Deleting #{relative_path_to(install_path)}" }
-            install_path.rmtree
-          end
+          install_repo = Git::Repository.new(environment,install_path)
+
+          if install_repo.git?
+            _install_path = relative_path_to(install_path)
+
+            if environment.git_destructive
+              debug { "Performing git hard reset of '#{_install_path}'" }
+
+              install_repo.reset_hard!
+              install_repo.clean!
+            end
+
+            if install_repo.dirty?
+                warn { "#{install_repo.dirty?}, skipping..." }
+            else
+              # Try to do nicer git operations when possible
+              _remote_repo = 'librarian_origin'
+
+              begin
+                Librarian::Posix.run!(%W{git remote add #{_remote_repo} #{repository_cache_path}}, :chdir => _install_path)
+              rescue Librarian::Posix::CommandFailure => e
+                unless e.to_s =~ /already exists/
+                  raise Error, "Could not update git repository at #{_install_path}"
+                end
+              end
+
+              install_repo.fetch!(_remote_repo)
+
+              if environment.verbose?
+                warn "Checking out #{ref} in #{_install_path}"
+              end
+              install_repo.checkout!(ref)
 
-          install_perform_step_copy!(found_path, install_path)
+              begin
+                _target_ref = ref
+
+                # Handle branches vs absolute refs
+                if repository.remote_branch_names[repository.default_remote].include?(_target_ref)
+                  _target_ref = "#{repository.default_remote}/#{_target_ref}"
+                end
+
+                ff_output = Librarian::Posix.run!(%W{git pull --ff-only #{_remote_repo} #{_target_ref}}, :chdir => _install_path)
+
+                if ff_output =~ /Updating\s+.*\.\.(.*)\s*$/
+                  warn { "Updated '#{_install_path}' to #{$1}" }
+                end
+              rescue Librarian::Posix::CommandFailure => e
+                warn { "Fast forward of git repo at '#{_install_path}' failed...skipping" }
+              end
+
+              begin
+                Librarian::Posix.run!(%W{git remote rm #{_remote_repo}}, :chdir => _install_path)
+              rescue Librarian::Posix::CommandFailure => e
+                # We don't really care if this fails.
+                debug { "Removal of the '#{_remote_repo}' git remote failed" }
+              end
+            end
+          else
+            if install_path.exist? && rsync? != true
+              debug { "Deleting #{relative_path_to(install_path)}" }
+              install_path.rmtree
+            end
+
+            install_perform_step_copy!(found_path, install_path)
+          end
         end
 
         def fetch_version(name, extra)

lib/librarian/puppet/version.rb

@@ -1,5 +1,5 @@
 module Librarian
   module Puppet
-    VERSION = "2.2.1"
+    VERSION = "2.2.3"
   end
 end