1 files changed, 71 insertions, 0 deletions
diff --git a/charms/trusty/ceilometer/charmhelpers/contrib/hardening/templating.py b/charms/trusty/ceilometer/charmhelpers/contrib/hardening/templating.py
new file mode 100644
index 0000000..d2ab7dc
--- /dev/null
+++ b/charms/trusty/ceilometer/charmhelpers/contrib/hardening/templating.py
@@ -0,0 +1,71 @@
+# Copyright 2016 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.hookenv import (
+    log,
+    DEBUG,
+    WARNING,
+)
+
+try:
+    from jinja2 import FileSystemLoader, Environment
+except ImportError:
+    from charmhelpers.fetch import apt_install
+    from charmhelpers.fetch import apt_update
+    apt_update(fatal=True)
+    apt_install('python-jinja2', fatal=True)
+    from jinja2 import FileSystemLoader, Environment
+
+
+# NOTE: function separated from main rendering code to facilitate easier
+#       mocking in unit tests.
+def write(path, data):
+    with open(path, 'wb') as out:
+        out.write(data)
+
+
+def get_template_path(template_dir, path):
+    """Returns the template file which would be used to render the path.
+
+    The path to the template file is returned.
+    :param template_dir: the directory the templates are located in
+    :param path: the file path to be written to.
+    :returns: path to the template file
+    """
+    return os.path.join(template_dir, os.path.basename(path))
+
+
+def render_and_write(template_dir, path, context):
+    """Renders the specified template into the file.
+
+    :param template_dir: the directory to load the template from
+    :param path: the path to write the templated contents to
+    :param context: the parameters to pass to the rendering engine
+    """
+    env = Environment(loader=FileSystemLoader(template_dir))
+    template_file = os.path.basename(path)
+    template = env.get_template(template_file)
+    log('Rendering from template: %s' % template.name, level=DEBUG)
+    rendered_content = template.render(context)
+    if not rendered_content:
+        log("Render returned None - skipping '%s'" % path,
+            level=WARNING)
+        return
+
+    write(path, rendered_content.encode('utf-8').strip())
+    log('Wrote template %s' % path, level=DEBUG)