# HG changeset patch
# User Tero Marttila <terom@qmsk.net>
# Date 1412376054 -10800
# Node ID 0ff809f855f76bcc92bd63908c7388aa69e29910
# Parent  c756bbcbc102b62dc8f3f9d0c5acacbbc2c619ee
pngtile.tile: implement Last-Modified/If-Modified-Since caching

diff -r c756bbcbc102 -r 0ff809f855f7 pngtile/tile.py
--- a/pngtile/tile.py	Sat Oct 04 01:40:40 2014 +0300
+++ b/pngtile/tile.py	Sat Oct 04 01:40:54 2014 +0300
@@ -124,28 +124,6 @@
 
         return redirect(self.image_url(name))
 
-    def handle_region (self, request):
-        """
-            Return image/png for given region.
-        """
-
-        image, name = self.open(request.path)
- 
-        png = self.render_region(request, image)
-        
-        return Response(png, content_type='image/png')
-
-    def handle_tile (self, request):
-        """
-            Return image/png for given tile.
-        """
-
-        image, name = self.open(request.path)
-            
-        png = self.render_tile(request, image)
-        
-        return Response(png, content_type='image/png')
-
     def handle (self, request):
         """
             Handle request for an image
@@ -161,11 +139,30 @@
             return self.handle_image(request, name, path)
 
         elif 'w' in request.args and 'h' in request.args and 'x' in request.args and 'y' in request.args:
-            return self.handle_region(request)
+            render_func = self.render_region
 
         elif 'x' in request.args and 'y' in request.args:
-            return self.handle_tile(request)
+            render_func = self.render_tile
 
         else:
             raise exceptions.BadRequest("Unknown args")
+        
+        # handle image
+        image, name = self.open(request.path)
 
+        # http caching
+        mtime = image.cache_mtime()
+
+        if request.if_modified_since and mtime == request.if_modified_since:
+            return Response(status=304)
+            
+        # render
+        png = render_func(request, image)
+        
+        # response
+        response = Response(png, content_type='image/png')
+        response.last_modified = mtime
+
+        return response
+
+