Remove cheetah from templater (#1416)

Remove cheetah template code

- cheetah was dropped as a requirement in 17.1
- we still have cheetah template code
- cheetah test fails
- no known users - remove rather than fix

3 files changed, 5 insertions, 79 deletions

diff --git a/cloudinit/templater.py b/cloudinit/templater.py
index d8af5096..298eaf6b 100644
--- a/cloudinit/templater.py
+++ b/cloudinit/templater.py
@@ -15,13 +15,6 @@ import re
 import sys
 
 try:
-    from Cheetah.Template import Template as CTemplate
-
-    CHEETAH_AVAILABLE = True
-except (ImportError, AttributeError):
-    CHEETAH_AVAILABLE = False
-
-try:
     from jinja2 import DebugUndefined as JUndefined
     from jinja2 import Template as JTemplate
 
@@ -96,9 +89,6 @@ def basic_render(content, params):
 
 
 def detect_template(text):
-    def cheetah_render(content, params):
-        return CTemplate(content, searchList=[params]).respond()
-
     def jinja_render(content, params):
         # keep_trailing_newline is in jinja2 2.7+, not 2.6
         add = "\n" if content.endswith("\n") else ""
@@ -119,14 +109,10 @@ def detect_template(text):
         rest = ""
     type_match = TYPE_MATCHER.match(ident)
     if not type_match:
-        if CHEETAH_AVAILABLE:
-            LOG.debug("Using Cheetah as the renderer for unknown template.")
-            return ("cheetah", cheetah_render, text)
-        else:
-            return ("basic", basic_render, text)
+        return ("basic", basic_render, text)
     else:
         template_type = type_match.group(1).lower().strip()
-        if template_type not in ("jinja", "cheetah", "basic"):
+        if template_type not in ("jinja", "basic"):
             raise ValueError(
                 "Unknown template rendering type '%s' requested"
                 % template_type
@@ -139,14 +125,6 @@ def detect_template(text):
             return ("basic", basic_render, rest)
         elif template_type == "jinja" and JINJA_AVAILABLE:
             return ("jinja", jinja_render, rest)
-        if template_type == "cheetah" and not CHEETAH_AVAILABLE:
-            LOG.warning(
-                "Cheetah not available as the selected renderer for"
-                " desired template, reverting to the basic renderer."
-            )
-            return ("basic", basic_render, rest)
-        elif template_type == "cheetah" and CHEETAH_AVAILABLE:
-            return ("cheetah", cheetah_render, rest)
         # Only thing left over is the basic renderer (it is always available).
         return ("basic", basic_render, rest)
 
@@ -154,12 +132,7 @@ def detect_template(text):
 def render_from_file(fn, params):
     if not params:
         params = {}
-    # jinja in python2 uses unicode internally.  All py2 str will be decoded.
-    # If it is given a str that has non-ascii then it will raise a
-    # UnicodeDecodeError.  So we explicitly convert to unicode type here.
-    template_type, renderer, content = detect_template(
-        util.load_file(fn, decode=False).decode("utf-8")
-    )
+    template_type, renderer, content = detect_template(util.load_file(fn))
     LOG.debug("Rendering content of '%s' using renderer %s", fn, template_type)
     return renderer(content, params)
 
@@ -170,15 +143,13 @@ def render_to_file(fn, outfn, params, mode=0o644):
 
 
 def render_string_to_file(content, outfn, params, mode=0o644):
-    """Render string (or py2 unicode) to file.
-    Warning: py2 str with non-ascii chars will cause UnicodeDecodeError."""
+    """Render string"""
     contents = render_string(content, params)
     util.write_file(outfn, contents, mode=mode)
 
 
 def render_string(content, params):
-    """Render string (or py2 unicode).
-    Warning: py2 str with non-ascii chars will cause UnicodeDecodeError."""
+    """Render string"""
     if not params:
         params = {}
     _template_type, renderer, content = detect_template(content)
@@ -196,6 +167,3 @@ def render_cloudcfg(variant, template, output):
         sys.stdout.write(contents)
     else:
         write_file(output, contents, omode="w")
-
-
-# vi: ts=4 expandtab
diff --git a/tests/unittests/__init__.py b/tests/unittests/__init__.py
index 657cb399..e69de29b 100644
--- a/tests/unittests/__init__.py
+++ b/tests/unittests/__init__.py
@@ -1,12 +0,0 @@
-# This file is part of cloud-init. See LICENSE file for license information.
-
-try:
-    # For test cases, avoid the following UserWarning to stderr:
-    # You don't have the C version of NameMapper installed ...
-    from Cheetah import NameMapper as _nm
-
-    _nm.C_VERSION = True
-except ImportError:
-    pass
-
-# vi: ts=4 expandtab
diff --git a/tests/unittests/test_templating.py b/tests/unittests/test_templating.py
index 3a0195bf..0cdedbe7 100644
--- a/tests/unittests/test_templating.py
+++ b/tests/unittests/test_templating.py
@@ -10,14 +10,6 @@ from cloudinit import templater
 from cloudinit.util import load_file, write_file
 from tests.unittests import helpers as test_helpers
 
-try:
-    import Cheetah
-
-    HAS_CHEETAH = True
-    c = Cheetah  # make pyflakes and pylint happy, as Cheetah is not used here
-except ImportError:
-    HAS_CHEETAH = False
-
 
 class TestTemplates(test_helpers.CiTestCase):
 
@@ -52,28 +44,6 @@ class TestTemplates(test_helpers.CiTestCase):
         out_data = templater.basic_render(in_data, {"b": 2})
         self.assertEqual(expected_data.strip(), out_data)
 
-    @test_helpers.skipIf(not HAS_CHEETAH, "cheetah renderer not available")
-    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 $blah"
-        (template_type, _renderer, _contents) = templater.detect_template(blob)
-        self.assertIn("cheetah", template_type)
-        self.assertEqual(blob, contents)
-
-        blob = "##template:something-new"
-        self.assertRaises(ValueError, templater.detect_template, blob)
-
-    def test_render_cheetah(self):
-        blob = """## template:cheetah
-$a,$b"""
-        c = templater.render_string(blob, {"a": 1, "b": 2})
-        self.assertEqual("1,2", c)
-
     def test_render_jinja(self):
         blob = """## template:jinja
 {{a}},{{b}}"""