Added custom template loader to CMS in order to enable {% include %} and {% import %} in jinja temp…

sitescripts/cms/sources.py

 # coding: utf-8
 
 # This file is part of the Adblock Plus web scripts,
 # Copyright (C) 2006-2013 Eyeo GmbH
 #
 # Adblock Plus 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.
 #
 # Adblock Plus 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 Adblock Plus.  If not, see <http://www.gnu.org/licenses/>.
 
 import sys, os, subprocess, zipfile, json, urlparse, codecs
 from StringIO import StringIO
 from ConfigParser import SafeConfigParser
+import jinja2
 
 class Source:
   def resolve_link(self, url, locale):
     parsed = urlparse.urlparse(url)
     page = parsed.path
     if parsed.scheme != "" or page.startswith("/") or page.startswith("."):
       # Not a page link
       return None, None
 
     if parsed.path == "" and url != "":
@@ skipping 128 matching lines @@
   # Template helpers
   #
 
   @staticmethod
   def template_filename(template):
     return "templates/%s.tmpl" % template
 
   def read_template(self, template):
     return self.read_file(self.template_filename(template))
 
+  def get_template_loader(self):
+    return SourceLoader(self)
+
   #
   # Include helpers
   #
 
   @staticmethod
   def include_filename(include, format):
     return "includes/%s.%s" % (include, format)
 
   def has_include(self, include, format):
     return self.has_file(self.include_filename(include, format))
@@ skipping 73 matching lines @@
         return
 
       for filename in files:
         path = os.path.join(dir, filename)
         if os.path.isfile(path):
           result.append(relpath + filename)
         elif os.path.isdir(path):
           do_list(path, relpath + filename + "/")
     do_list(self.get_path(subdir), "")
     return result
+
+class SourceLoader(jinja2.BaseLoader):

[Wladimir Palant, 2013/12/11 18:46:02]

I don't think that Jinja-specific functionality belongs into sources.py - this
should be a private class of TemplateConverter, inside converters.py.

+  def __init__(self, source):
+    self.source = source
+
+  def get_source(self, environment, template):
+    try:
+      return self.source.read_file(template + '.tmpl'), None, None

[Wladimir Palant, 2013/12/11 18:46:02]

I think this should be self.source.read_include(template, "tmpl") - we want to
use paths relative to the includes directory.

[Sebastian Noack, 2013/12/11 22:20:14]

I've already addressed that, but I would like to undo that change, because the
template loader isn't only used for includes but also for imports and extends
(template inheritance). While you can argue whether imports are some kind of
includes, extends definetly aren't. Templates you extend from can and often will
also be rendered on their own. Beside that putting templates into the includes
subdir will also make them available for <? include ... ?>. But there is no
point in including templates that behave as library (only provide variables and
macros that can be imported) or that exist in order to extend them. What do you
think?

[Wladimir Palant, 2013/12/12 07:16:54]

Yes, you are right. We might want to extend the default template meaning that we
will have to address a template in the templates folder. Ok, let's have the
paths relative to the root here.

Nevertheless, the template with the team data should be located in the includes
directory.

+    except Exception:
+      raise jinja2.TemplateNotFound(template)