Add UID generating recipe

setup.py

@@ -119,6 +119,7 @@ setup(name=name,
           'stunnel = slapos.recipe.stunnel:Recipe',
           'testnode = slapos.recipe.testnode:Recipe',
           'urlparse = slapos.recipe._urlparse:Recipe',
+          'uuid = slapos.recipe._uuid:Recipe',
           'vifib = slapos.recipe.vifib:Recipe',
           'waitfor = slapos.recipe.waitfor:Recipe',
           'xvfb = slapos.recipe.xvfb:Recipe',

slapos/recipe/_uuid.py

+##############################################################################
+#
+# Copyright (c) 2010 Vifib SARL and Contributors. All Rights Reserved.
+#
+# WARNING: This program as such is intended to be used by professional
+# programmers who take the whole responsibility of assessing all potential
+# consequences resulting from its eventual inadequacies and bugs
+# End users who are looking for a ready-to-use solution with commercial
+# guarantees and support are strongly adviced to contract a Free Software
+# Service Company
+#
+# This program 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.
+#
+# This program 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 this program; if not, write to the Free Software
+# Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
+#
+##############################################################################
+
+import uuid
+
+import os
+
+from slapos.recipe.librecipe import GenericBaseRecipe
+
+class Recipe(GenericBaseRecipe):
+
+    def _options(self, options):
+        write = True
+        if os.path.exists(options['cache-file']):
+            with open(options['cache-file'], 'r') as cache_file:
+                try:
+                    generated_uuid = uuid.UUID(hex=cache_file.read())
+                    write = False
+                except ValueError:
+                    generated_uuid = uuid.uuid4()
+        else:
+            generated_uuid = uuid.uuid4()
+
+        if write:
+            with open(options['cache-file'], 'w') as cache_file:
+                cache_file.write(generated_uuid.hex)
+
+        options['uuid'] = generated_uuid.hex
+
+    def install(self):
+        return [self.options['cache-file']]