Allow the usage of jinja2 templates

This drops the hard requirement on Cheetah.

Jinja is a python 2.4->3.x compatible templating engine, allow its
optional usage (until we can depreciate cheetah) by allowing for
specifying a template file header that can define which template engine to
use.

If the template file header does not specify a renderer, then assume
that that is cheetah.  If cheetah is not available, then use a limited
builtin renderer on a best effort basis, and log the warning.

LP: #1219223

1 files changed, 107 insertions, 0 deletions

diff --git a/tests/unittests/test_templating.py b/tests/unittests/test_templating.py
new file mode 100644
index 00000000..1ec3004b
--- /dev/null
+++ b/tests/unittests/test_templating.py
@@ -0,0 +1,107 @@
+# vi: ts=4 expandtab
+#
+#    Copyright (C) 2014 Yahoo! Inc.
+#
+#    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/>.
+
+from tests.unittests import helpers as test_helpers
+import textwrap
+
+from cloudinit import templater
+
+
+class TestTemplates(test_helpers.TestCase):
+    def test_render_basic(self):
+        in_data = textwrap.dedent("""
+            ${b}
+
+            c = d
+            """)
+        in_data = in_data.strip()
+        expected_data = textwrap.dedent("""
+            2
+
+            c = d
+            """)
+        out_data = templater.basic_render(in_data, {'b': 2})
+        self.assertEqual(expected_data.strip(), out_data)
+
+    def test_detection(self):
+        blob = "## template:cheetah"
+
+        (template_type, renderer, contents) = templater.detect_template(blob)
+        self.assertIn("cheetah", template_type)
+        self.assertEqual("", contents.strip())
+
+        blob = "blahblah $blah"
+        (template_type, renderer, contents) = templater.detect_template(blob)
+        self.assertIn("cheetah", template_type)
+        self.assertEquals(blob, contents)
+
+        blob = '##template:something-new'
+        self.assertRaises(ValueError, templater.detect_template, blob)
+
+    def test_render_cheetah(self):
+        blob = '''## template:cheetah
+$a,$b'''
+        c = templater.render_string(blob, {"a": 1, "b": 2})
+        self.assertEquals("1,2", c)
+
+    def test_render_jinja(self):
+        blob = '''## template:jinja
+{{a}},{{b}}'''
+        c = templater.render_string(blob, {"a": 1, "b": 2})
+        self.assertEquals("1,2", c)
+
+    def test_render_default(self):
+        blob = '''$a,$b'''
+        c = templater.render_string(blob, {"a": 1, "b": 2})
+        self.assertEquals("1,2", c)
+
+    def test_render_basic_deeper(self):
+        hn = 'myfoohost.yahoo.com'
+        expected_data = "h=%s\nc=d\n" % hn
+        in_data = "h=$hostname.canonical_name\nc=d\n"
+        params = {
+            "hostname": {
+                "canonical_name": hn,
+            },
+        }
+        out_data = templater.render_string(in_data, params)
+        self.assertEqual(expected_data, out_data)
+
+    def test_render_basic_no_parens(self):
+        hn = "myfoohost"
+        in_data = "h=$hostname\nc=d\n"
+        expected_data = "h=%s\nc=d\n" % hn
+        out_data = templater.basic_render(in_data, {'hostname': hn})
+        self.assertEqual(expected_data, out_data)
+
+    def test_render_basic_parens(self):
+        hn = "myfoohost"
+        in_data = "h = ${hostname}\nc=d\n"
+        expected_data = "h = %s\nc=d\n" % hn
+        out_data = templater.basic_render(in_data, {'hostname': hn})
+        self.assertEqual(expected_data, out_data)
+
+    def test_render_basic2(self):
+        mirror = "mymirror"
+        codename = "zany"
+        in_data = "deb $mirror $codename-updates main contrib non-free"
+        ex_data = "deb %s %s-updates main contrib non-free" % (mirror, codename)
+
+        out_data = templater.basic_render(in_data,
+            {'mirror': mirror, 'codename': codename})
+        self.assertEqual(ex_data, out_data)