+from django import template
+from django.db import models
+from django.core.cache import cache
+
+register = template.Library()
+
+Chunk = models.get_model('chunks', 'chunk')
+CACHE_PREFIX = "chunk_"
+
+def do_get_chunk(parser, token):
+ # split_contents() knows not to split quoted strings.
+ tokens = token.split_contents()
+ if len(tokens) < 2 or len(tokens) > 3:
+ raise template.TemplateSyntaxError, "%r tag should have either 2 or 3 arguments" % (tokens[0],)
+ if len(tokens) == 2:
+ tag_name, key = tokens
+ cache_time = 0
+ if len(tokens) == 3:
+ tag_name, key, cache_time = tokens
+ # Check to see if the key is properly double/single quoted
+ if not (key[0] == key[-1] and key[0] in ('"', "'")):
+ raise template.TemplateSyntaxError, "%r tag's argument should be in quotes" % tag_name
+ # Send key without quotes and caching time
+ return ChunkNode(key[1:-1], cache_time)
+
+class ChunkNode(template.Node):
+ def __init__(self, key, cache_time=0):
+ self.key = key
+ self.cache_time = cache_time
+
+ def render(self, context):
+ try:
+ cache_key = CACHE_PREFIX + self.key
+ c = cache.get(cache_key)
+ if c is None:
+ c = Chunk.objects.get(key=self.key)
+ cache.set(cache_key, c, int(self.cache_time))
+ content = c.content
+ except Chunk.DoesNotExist:
+ n = Chunk(key=self.key)
+ n.save()
+ return ''
+ return content
+
+register.tag('chunk', do_get_chunk)