From dae109748bcdb5a700ef41de716e74a327eef917 Mon Sep 17 00:00:00 2001
From: "arne@rcs4u.de" <arne@rcs4u.de@cfb8ba98-e953-0410-9cff-959ffddf5974>
Date: Thu, 17 Apr 2008 10:20:09 +0000
Subject: [PATCH] added filesystem-based caching of dbtemplates (configured via
 settings.DBTEMPLATES_CACHE_DIR). docs and tests still missing.

git-svn-id: https://django-dbtemplates.googlecode.com/svn/trunk@22 cfb8ba98-e953-0410-9cff-959ffddf5974

committer: arne@rcs4u.de <arne@rcs4u.de@cfb8ba98-e953-0410-9cff-959ffddf5974>

--HG--
extra : convert_revision : 633aadf3de216f42398f8c57a93d68c28946da3a
---
 dbtemplates/loader.py | 42 +++++++++++++++++++++++++++++++++++++-----
 1 file changed, 37 insertions(+), 5 deletions(-)

diff --git a/dbtemplates/loader.py b/dbtemplates/loader.py
index f2b4fd4..1762725 100644
--- a/dbtemplates/loader.py
+++ b/dbtemplates/loader.py
@@ -1,4 +1,7 @@
+import os
 from django.conf import settings
+from django.dispatch import dispatcher
+from django.db.models import signals
 from django.template import TemplateDoesNotExist
 from django.contrib.sites.models import Site
 
@@ -9,16 +12,45 @@ try:
 except:
     site = None
 
+try:
+    cache_dir = os.path.normpath(getattr(settings, 'DBTEMPLATES_CACHE_DIR', None))
+    if not os.path.isdir(cache_dir):
+        raise
+except:
+    cache_dir = None
+    
 def load_template_source(template_name, template_dirs=None):
     """
     Loads templates from the database by querying the database field ``name``
     with a template path and ``sites`` with the current site.
     """
     if site is not None:
+        if cache_dir is not None:
+            filepath = os.path.join(cache_dir, template_name)
         try:
-            t = Template.objects.get(name__exact=template_name, sites__pk=site.id)
-            return (t.content, 'db:%s:%s' % (settings.DATABASE_ENGINE, template_name))
-        except:
-            pass
+            return (open(filepath).read(), filepath)
+        except IOError:
+            try:
+                t = Template.objects.get(name__exact=template_name, sites__pk=site.id)
+                try:
+                    f = open(filepath, 'w')
+                    f.write(t.content)
+                    f.close()
+                except IOError:
+                        pass
+                return (t.content, 'db:%s:%s' % (settings.DATABASE_ENGINE, template_name))
+            except:
+                pass
     raise TemplateDoesNotExist, template_name
-load_template_source.is_usable = True
\ No newline at end of file
+load_template_source.is_usable = True
+
+def remove_cached_template(instance):
+    try:
+        filepath = os.path.join(cache_dir, instance.name)
+        os.remove(filepath)
+    except OSError:
+        pass
+
+dispatcher.connect(remove_cached_template, sender=Template, signal=signals.post_save)
+dispatcher.connect(remove_cached_template, sender=Template, signal=signals.pre_delete)
+