lib/ey-deploy/deploy_hook.rb in ey-deploy-0.3.1 vs lib/ey-deploy/deploy_hook.rb in ey-deploy-0.3.2

@@ -22,10 +22,11 @@
     end
 
     class CallbackContext
       def initialize(hook_runner, config)
         @hook_runner, @configuration = hook_runner, config
+        @node = node
       end
 
       def method_missing(meth, *args, &blk)
         if @configuration.respond_to?(meth)
           @configuration.send(meth, *args, &blk)
@@ -42,9 +43,37 @@
         system(@hook_runner.prepare_run(cmd))
       end
 
       def sudo(cmd)
         system(@hook_runner.prepare_sudo(cmd))
+      end
+
+      # convenience functions for running on certain instance types
+      def on_app_master(&blk)                 on_roles(%w[solo app_master],          &blk) end
+      def on_app_servers(&blk)                on_roles(%w[solo app_master app],      &blk) end
+      def on_db_master(&blk)                  on_roles(%w[solo db_master],           &blk) end
+      def on_db_slaves(&blk)                  on_roles(%w[db_slave],                 &blk) end
+      def on_db_servers(&blk)                 on_roles(%w[solo db_master db_slave],  &blk) end
+      def on_app_servers_and_utilities(&blk)  on_roles(%w[solo app_master app util], &blk) end
+
+      def on_utilities(*names, &blk)
+        names.flatten!
+        on_roles(%w[util]) do
+          blk.call if names.empty? || names.include?(current_name)
+        end
+      end
+
+      private
+      def on_roles(desired_roles)
+        yield if desired_roles.include?(current_role.to_s)
+      end
+
+      def current_role
+        node[:instance_role]
+      end
+
+      def current_name
+        node[:name]
       end
     end
 
   end
 end