add new message object

Signed-off-by: Nico Schottelius <nico@bento.schottelius.org>

cdist/core/message.py

@@ -0,0 +1,66 @@
+# -*- coding: utf-8 -*-
+#
+# 2013 Nico Schottelius (nico-cdist at schottelius.org)
+#
+# This file is part of cdist.
+#
+# cdist is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation, either version 3 of the License, or
+# (at your option) any later version.
+#
+# cdist is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with cdist. If not, see <http://www.gnu.org/licenses/>.
+#
+#
+
+import logging
+import shutil
+import tempfile
+
+import cdist
+
+log = logging.getLogger(__name__)
+
+
+class Message(object):
+    """Support messaging between types
+
+    """
+    def __init__(self, prefix, global_messages):
+        self.prefix = prefix
+        self.global_messages = global_messages
+
+        self.messages_in  = tempfile.mkstemp(suffix='.cdist_message_in')
+        self.messages_out = tempfile.mkstemp(suffix='.cdist_message_out')
+
+        shutil.copyfile(self.global_messages, self.messages_in)
+
+    @property
+    def env(self, env):
+        env = {}
+        env['__messages_in']  = self.messages_in
+        env['__messages_out'] = self.messages_out
+
+        return env
+
+    def _cleanup(self):
+        os.remove(self.messages_in)
+        os.remove(self.messages_out)
+
+    def _merge_messages(self):
+        with open(self.messages_in) as fd:
+            content = fd.readlines()
+
+        with open(self.global_messages, 'a') as fd:
+            for line in content:
+                fd.write("%s:%s" % (self.prefix, line))
+
+    def merge_messages(self):
+        self._merge_messages()
+        self._cleanup()