add more stuffs to mako mixin

torneira/template/mako_engine.py

@@ -1,19 +1,36 @@
 # coding: utf-8
-from mako.exceptions import TopLevelLookupException
+import logging
+from mako.exceptions import TopLevelLookupException, html_error_template
 from mako.lookup import TemplateLookup
 from tornado.web import HTTPError
 
 from torneira import settings
 
 
 class MakoMixin(object):
+
     def render_to_template(self, template_name, **context):
         assert hasattr(settings, 'TEMPLATE_DIRS'), "Missing TEMPLATE_DIRS config"
 
-        lookup = TemplateLookup(directories=settings.TEMPLATE_DIRS, input_encoding='utf-8', output_encoding='utf-8', default_filters=['decode.utf8'])
+        lookup = TemplateLookup(directories=settings.TEMPLATE_DIRS,
+            input_encoding='utf-8', output_encoding='utf-8',
+            default_filters=['decode.utf8'])
+
         try:
             template = lookup.get_template(template_name)
         except TopLevelLookupException:
             raise HTTPError(500, "Template %s not found" % template_name)
 
-        return template.render(**context)
+        context.update({
+            'settings': settings,
+            'url_for': self.reverse_url
+        })
+
+        try:
+            return template.render(**context)
+        except Exception, e:
+            if settings.DEBUG:
+                return html_error_template().render()
+            else:
+                logging.exception("Template %s could not be rendered" % template_name)
+                raise e