1 files changed, 68 insertions, 0 deletions
diff --git a/charms/trusty/keepalived/hooks/charmhelpers/core/templating.py b/charms/trusty/keepalived/hooks/charmhelpers/core/templating.py
new file mode 100644
index 0000000..4531999
--- /dev/null
+++ b/charms/trusty/keepalived/hooks/charmhelpers/core/templating.py
@@ -0,0 +1,68 @@
+# Copyright 2014-2015 Canonical Limited.
+#
+# This file is part of charm-helpers.
+#
+# charm-helpers is free software: you can redistribute it and/or modify
+# it under the terms of the GNU Lesser General Public License version 3 as
+# published by the Free Software Foundation.
+#
+# charm-helpers 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 Lesser General Public License for more details.
+#
+# You should have received a copy of the GNU Lesser General Public License
+# along with charm-helpers.  If not, see <http://www.gnu.org/licenses/>.
+
+import os
+
+from charmhelpers.core import host
+from charmhelpers.core import hookenv
+
+
+def render(source, target, context, owner='root', group='root',
+           perms=0o444, templates_dir=None, encoding='UTF-8'):
+    """
+    Render a template.
+
+    The `source` path, if not absolute, is relative to the `templates_dir`.
+
+    The `target` path should be absolute.
+
+    The context should be a dict containing the values to be replaced in the
+    template.
+
+    The `owner`, `group`, and `perms` options will be passed to `write_file`.
+
+    If omitted, `templates_dir` defaults to the `templates` folder in the charm.
+
+    Note: Using this requires python-jinja2; if it is not installed, calling
+    this will attempt to use charmhelpers.fetch.apt_install to install it.
+    """
+    try:
+        from jinja2 import FileSystemLoader, Environment, exceptions
+    except ImportError:
+        try:
+            from charmhelpers.fetch import apt_install
+        except ImportError:
+            hookenv.log('Could not import jinja2, and could not import '
+                        'charmhelpers.fetch to install it',
+                        level=hookenv.ERROR)
+            raise
+        apt_install('python-jinja2', fatal=True)
+        from jinja2 import FileSystemLoader, Environment, exceptions
+
+    if templates_dir is None:
+        templates_dir = os.path.join(hookenv.charm_dir(), 'templates')
+    loader = Environment(loader=FileSystemLoader(templates_dir))
+    try:
+        source = source
+        template = loader.get_template(source)
+    except exceptions.TemplateNotFound as e:
+        hookenv.log('Could not load template %s from %s.' %
+                    (source, templates_dir),
+                    level=hookenv.ERROR)
+        raise e
+    content = template.render(context)
+    host.mkdir(os.path.dirname(target), owner, group, perms=0o755)
+    host.write_file(target, content.encode(encoding), owner, group, perms)