1 files changed, 65 insertions, 0 deletions
diff --git a/cloudinit/importer.py b/cloudinit/importer.py
new file mode 100644
index 00000000..71cf2726
--- /dev/null
+++ b/cloudinit/importer.py
@@ -0,0 +1,65 @@
+# vi: ts=4 expandtab
+#
+#    Copyright (C) 2012 Canonical Ltd.
+#    Copyright (C) 2012 Hewlett-Packard Development Company, L.P.
+#    Copyright (C) 2012 Yahoo! Inc.
+#
+#    Author: Scott Moser <scott.moser@canonical.com>
+#    Author: Juerg Haefliger <juerg.haefliger@hp.com>
+#    Author: Joshua Harlow <harlowja@yahoo-inc.com>
+#
+#    This program is free software: you can redistribute it and/or modify
+#    it under the terms of the GNU General Public License version 3, as
+#    published by the Free Software Foundation.
+#
+#    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, see <http://www.gnu.org/licenses/>.
+
+import sys
+
+from cloudinit import log as logging
+
+LOG = logging.getLogger(__name__)
+
+
+def import_module(module_name):
+    __import__(module_name)
+    return sys.modules[module_name]
+
+
+def find_module(base_name, search_paths, required_attrs=None):
+    found_places = []
+    if not required_attrs:
+        required_attrs = []
+    real_paths = []
+    for path in search_paths:
+        real_path = []
+        if path:
+            real_path.extend(path.split("."))
+        real_path.append(base_name)
+        full_path = '.'.join(real_path)
+        real_paths.append(full_path)
+    LOG.debug("Looking for modules %s that have attributes %s",
+              real_paths, required_attrs)
+    for full_path in real_paths:
+        mod = None
+        try:
+            mod = import_module(full_path)
+        except ImportError:
+            pass
+        if not mod:
+            continue
+        found_attrs = 0
+        for attr in required_attrs:
+            if hasattr(mod, attr):
+                found_attrs += 1
+        if found_attrs == len(required_attrs):
+            found_places.append(full_path)
+    LOG.debug("Found %s with attributes %s in %s", base_name,
+              required_attrs, found_places)
+    return found_places