Add bazaar-ng SCM module [Damien Merenne]

git-svn-id: http://svn.rubyonrails.org/rails/tools/switchtower@3489 5ecf4fe2-1ee6-0310-87b1-e25e094e27de

CHANGELOG

@@ -1,5 +1,7 @@
 *0.11.0* *SVN*
 
+* Add bazaar-ng SCM module [Damien Merenne]
+
 * Add optional :svn_username and :svn_password variables
 
 * Allow Proc-valued variables to be set more conveniently (set(:foo) { "bar" })

THANKS

@@ -1,2 +1,3 @@
 * Bazaar (v1) SCM Module: Edd Dumbill <edd@usefulinc.com>
-* Perforce SCM Module: Richard McMahon <richie.mcmahon@gmail.com>
+* Perforce SCM Module: Richard McMahon <richie.mcmahon@gmail.com>
+* Bazaar-NG SCM Module: Damien Merenne <dam@capsule.org>

lib/switchtower/scm/bzr.rb

@@ -0,0 +1,70 @@
+require 'switchtower/scm/base'
+
+module SwitchTower
+  module SCM
+
+    # An SCM module for using Bazaar-NG (bzr) as your source control tool.
+    # You can use it by placing the following line in your configuration:
+    #
+    #   set :scm, :bzr
+    #
+    # Also, this module accepts a <tt>:bzr</tt> configuration variable,
+    # which (if specified) will be used as the full path to the bzr
+    # executable on the remote machine:
+    #
+    #   set :bzr, "/opt/local/bin/bzr"
+    class Bzr < Base
+      # Return an integer identifying the last known revision in the bzr
+      # repository. (This integer is currently the revision number.) 
+      def latest_revision
+        `#{bzr} revno #{configuration.repository}`.to_i
+      end
+
+      # Return the number of the revision currently deployed.
+      def current_revision(actor)
+        command = "#{bzr} revno #{actor.release_path} &&"        
+        run_update(actor, command, &bzr_stream_handler(actor)) 
+      end
+
+      # Return a string containing the diff between the two revisions. +from+
+      # and +to+ may be in any format that bzr recognizes as a valid revision
+      # identifier. If +from+ is +nil+, it defaults to the last deployed
+      # revision. If +to+ is +nil+, it defaults to the last developed revision.
+      # Pay attention to the fact that as of now bzr does NOT support
+      # diff on remote locations.
+      def diff(actor, from=nil, to=nil)
+        from ||= current_revision(actor)
+        to ||= ""
+        `#{bzr} diff -r #{from}..#{to} #{configuration.repository}`
+      end
+
+      # Check out (on all servers associated with the current task) the latest
+      # revision. Uses the given actor instance to execute the command. If
+      # bzr asks for a password this will automatically provide it (assuming
+      # the requested password is the same as the password for logging into the
+      # remote server.)
+      def checkout(actor)
+        op = configuration[:checkout] || "branch"
+        command = "#{bzr} #{op} -r#{configuration.revision} #{configuration.repository} #{actor.release_path} &&"
+        run_checkout(actor, command, &bzr_stream_handler(actor)) 
+      end
+
+      def update(actor)
+        command = "cd #{actor.current_path} && #{bzr} pull -q &&"
+        run_update(actor, command, &bzr_stream_handler(actor)) 
+      end
+      
+      private
+        def bzr
+          configuration[:bzr] || "bzr"
+        end
+
+        def bzr_stream_handler(actor)
+          Proc.new do |ch, stream, out|
+            prefix = "#{stream} :: #{ch[:host]}"
+            actor.logger.info out, prefix
+          end
+        end
+    end
+  end
+end