Enable cache-busting URLs for CSS and JS

This will allow us to increase the cache times in the browser for our
CSS, which almost never changes.

Enables a new value to be used in templates, {{gitrev}}, which can be
used to bust pretty much any URL. We could do this for all the images
in the templates as well, but since most of them almost never change,
we'll just enable it manually for each individual image as it becomes
necessray - or just use a ?1, ?2 etc for those.

Enabled by default for CSS and JavaScript links, since those are much
more likely to be changed without having the URL changed.

Cache times aren't increased yet - we'll do that later one we're sure
that all existing caches are expired first.

pgweb/core/views.py

@@ -63,7 +63,7 @@ def home(request):
 		'quote': quote,
 		'versions': versions,
 		'planet': planet,
-	})
+	}, RequestContext(request))
 
 # Community main page (contains surveys and potentially more)
 def community(request):
@@ -244,7 +244,7 @@ def sync_timestamp(request):
 def admin_pending(request):
 	return render_to_response('core/admin_pending.html', {
 			'app_list': get_all_pending_moderations(),
-			})
+			}, RequestContext(request))
 
 # Purge objects from varnish, for the admin pages
 @login_required

pgweb/docs/views.py

@@ -1,6 +1,7 @@
 from django.shortcuts import render_to_response, get_object_or_404
 from django.http import HttpResponse, Http404, HttpResponseRedirect
 from django.template import TemplateDoesNotExist, loader, Context
+from django.template.context import RequestContext
 from django.contrib.auth.decorators import login_required
 from django.db.models import Q
 from django.conf import settings
@@ -67,7 +68,7 @@ def docpage(request, version, typ, filename):
 		'can_comment': (typ=="interactive" and ver==currver),
 		'doc_index_filename': indexname,
 		'loaddate': loaddate,
-	})
+	}, RequestContext(request))
 
 def docsrootpage(request, version, typ):
 	return docpage(request, version, typ, 'index')

pgweb/search/views.py

@@ -1,4 +1,5 @@
 from django.shortcuts import render_to_response, get_object_or_404
+from django.template.context import RequestContext
 from django.http import HttpResponse, Http404, HttpResponseRedirect
 from django.views.decorators.csrf import csrf_exempt
 from django.conf import settings
@@ -125,18 +126,18 @@ def search(request):
 					'listid': listid,
 					'dates': dateoptions,
 					'dateval': dateval,
-					})
+					}, RequestContext(request))
 		else:
 			return render_to_response('search/sitesearch.html', {
 					'search_error': "No search term specified.",
-					})
+					}, RequestContext(request))
 	query = request.REQUEST['q']
 
 	# Anti-stefan prevention
 	if len(query) > 1000:
 		return render_to_response('search/sitesearch.html', {
 			'search_error': "Search term too long.",
-			})
+			}, RequestContext(request))
 
 	# Is the request being paged?
 	if request.REQUEST.has_key('p'):
@@ -186,12 +187,12 @@ def search(request):
 			except socket.timeout:
 				return render_to_response('search/listsearch.html', {
 						'search_error': 'Timeout when talking to search server. Please try your search again later, or with a more restrictive search terms.',
-						})
+						}, RequestContext(request))
 			if r.status != 200:
 				memc = None
 				return render_to_response('search/listsearch.html', {
 						'search_error': 'Error talking to search server: %s' % r.reason,
-						})
+						}, RequestContext(request))
 			hits = json.loads(r.read())
 			if has_memcached and memc:
 				# Store them in memcached too! But only for 10 minutes...
@@ -236,7 +237,7 @@ def search(request):
 				'listid': listid,
 				'dates': dateoptions,
 				'dateval': dateval,
-				})
+				}, RequestContext(request))
 
 	else:
 		# Website search is still done by making a regular pgsql connection
@@ -247,7 +248,7 @@ def search(request):
 		except:
 			return render_to_response('search/sitesearch.html', {
 					'search_error': 'Could not connect to search database.'
-					})
+					}, RequestContext(request))
 
 		# perform the query for general web search
 		curs.execute("SELECT * FROM site_search(%(query)s, %(firsthit)s, %(hitsperpage)s, %(allsites)s, %(suburl)s)", {
@@ -283,4 +284,4 @@ def search(request):
 						'url': "%s%s" % (h[1], h[2]),
 						'abstract': h[4].replace("[[[[[[", "<b>").replace("]]]]]]","</b>"),
 						'rank': h[5]} for h in hits[:-1]],
-				})
+				}, RequestContext(request))

pgweb/settings.py

@@ -79,7 +79,7 @@ TEMPLATE_CONTEXT_PROCESSORS = (
 	'django.contrib.auth.context_processors.auth',
 	'django.contrib.messages.context_processors.messages',
 	'django.core.context_processors.media',
-	'util.contexts.RootLinkContextProcessor',
+	'util.contexts.PGWebContextProcessor',
 )
 
 LOGIN_URL='/account/login/'

pgweb/util/contexts.py

@@ -1,4 +1,5 @@
 from django.template import RequestContext
+from django.utils.functional import SimpleLazyObject
 from django.conf import settings
 
 # This is the whole site navigation structure. Stick in a smarter file?
@@ -100,12 +101,24 @@ class NavContext(RequestContext):
 		self.update({'navmenu': navsection})
 
 
-# Template context processor to add information about the root link
+def _get_gitrev():
-def RootLinkContextProcessor(request):
+	# Return the current git revision, that is used for
+	# cache-busting URLs.
+	with open('../.git/refs/heads/master') as f:
+		return f.readline()[:8]
+
+# Template context processor to add information about the root link and
+# the current git revision. git revision is returned as a lazy object so
+# we don't spend effort trying to load it if we don't need it (though
+# all general pages will need it since it's used to render the css urls)
+def PGWebContextProcessor(request):
+	gitrev = SimpleLazyObject(_get_gitrev)
 	if request.is_secure():
 		return {
 			'link_root': settings.SITE_ROOT,
+			'gitrev': gitrev,
 		}
 	else:
-		return {}
+		return {
-
+			'gitrev': gitrev,
+		}

templates/base/base.html

@@ -6,12 +6,12 @@
   <meta http-equiv="Content-Type" content="text/xhtml; charset=utf-8" />
 {%block meta%}{%endblock%} {# used for custom meta tags such as description which we don't want for every page #}
   <meta name="copyright" content="The PostgreSQL Global Development Group" />
-  <style type="text/css" media="screen" title="Normal Text">@import url("/dyncss/base.css");</style>
+  <style type="text/css" media="screen" title="Normal Text">@import url("/dyncss/base.css?{{gitrev}}");</style>
   <link rel="shortcut icon" href="/favicon.ico" />
-  <link rel="alternate stylesheet" type="text/css" media="screen" title="Large Text" href="/media/css/docs_large.css" />
+  <link rel="alternate stylesheet" type="text/css" media="screen" title="Large Text" href="/media/css/docs_large.css?{{gitrev}}" />
   <link rel="alternate" type="application/rss+xml" title="PostgreSQL News" href="{{link_root}}/news.rss" />
   <link rel="alternate" type="application/rss+xml" title="PostgreSQL Events" href="{{link_root}}/events.rss" />
-  <script async type="text/javascript" src="/media/js/styleswitcher.js"></script>
+  <script async type="text/javascript" src="/media/js/styleswitcher.js?{{gitrev}}"></script>
   <script type="text/javascript">
   var _gaq = _gaq || [];
   _gaq.push(['_setAccount', 'UA-1345454-1']);

templates/docs/docspage.html

@@ -2,10 +2,10 @@
 <html xmlns="http://www.w3.org/1999/xhtml" lang="en" xml:lang="en" dir="ltr">
 <head>
     <title>PostgreSQL: Documentation: {{page.display_version}}: {{page.title}}</title>
-    <style type="text/css" media="screen" title="Normal Text">@import url("/dyncss/docs.css");</style>
+    <style type="text/css" media="screen" title="Normal Text">@import url("/dyncss/docs.css?{{gitrev}}");</style>
     <link rel="alternate stylesheet" media="screen" href="/media/css/docs_large.css" type="text/css" title="Large Text" />
-    <script async type="text/javascript" src="/media/js/styleswitcher.js"></script>
+    <script async type="text/javascript" src="/media/js/styleswitcher.js?{{gitrev}}"></script>
-    <script type="text/javascript" src="/media/js/monospacefix.js"></script>
+    <script type="text/javascript" src="/media/js/monospacefix.js?{{gitrev}}"></script>
     <script type="text/javascript">
   var _gaq = _gaq || [];
   _gaq.push(['_setAccount', 'UA-1345454-1']);