HandlerFeedGenerator: Add caching

handlers/handlerfeedgenerator.cpp

@@ -43,7 +43,7 @@ std::vector<HandlerFeedGenerator::EntryRevisionPair> HandlerFeedGenerator::fetch
 	return result;
 }
 
-Response HandlerFeedGenerator::generateAtom(const std::vector<HandlerFeedGenerator::EntryRevisionPair> &entries,
+std::string HandlerFeedGenerator::generateAtom(const std::vector<HandlerFeedGenerator::EntryRevisionPair> &entries,
 											   std::string filter)
 {
 
@@ -89,11 +89,7 @@ Response HandlerFeedGenerator::generateAtom(const std::vector<HandlerFeedGenerat
 	atomheader.setVar("atomfeeduniqueid", utils::html_xss(this->urlProvider->atomFeed(filter)));
 	atomheader.setVar("atomfeedupdate", utils::formatLocalDate(newestPublished, dateformat) + "Z");
 
-	Response result;
-	result.setStatus(200);
-	result.setContentType("application/atom+xml");
-	result.setBody(atomheader.render() + stream.str());
-	return result;
+	return atomheader.render() + stream.str();
 }
 
 Response HandlerFeedGenerator::handleRequest(const Request &r)
@@ -103,12 +99,26 @@ Response HandlerFeedGenerator::handleRequest(const Request &r)
 	{
 		std::string type = r.get("type");
 		std::string categories = r.get("cats");
-
-		auto entries = fetchEntries(utils::split(categories, ','));
 		if(type == "atom")
 		{
 			std::string filter = categories;
-			response = generateAtom(entries, filter);
+			Response result;
+			result.setStatus(200);
+			result.setContentType("application/atom+xml");
+			std::string cacheKey = "feed:atom:" + filter;
+			auto cached = this->cache->get(cacheKey);
+			if(cached)
+			{
+				result.setBody(cached.value());
+			}
+			else
+			{
+				auto entries = fetchEntries(utils::split(categories, ','));
+				std::string feed = generateAtom(entries, filter);
+				result.setBody(feed);
+				this->cache->put(cacheKey, feed);
+			}
+			response = result;
 		}
 		else
 		{

handlers/handlerfeedgenerator.h

@@ -9,7 +9,7 @@ class HandlerFeedGenerator : public Handler
 
   protected:
 	std::vector<EntryRevisionPair> fetchEntries(std::vector<std::string> categories);
-	Response generateAtom(const std::vector<EntryRevisionPair> &entries, std::string atomtitle);
+	std::string generateAtom(const std::vector<EntryRevisionPair> &entries, std::string atomtitle);
 	Response generateRss(const std::vector<EntryRevisionPair> &entries);
 
   public:

handlers/handlerpagedelete.cpp

@@ -45,6 +45,7 @@ Response HandlerPageDelete::handleRequest(PageDao &pageDao, std::string pagename
 		{
 			pageDao.deletePage(pagename);
 			this->cache->removePrefix("page:"); // TODO: overkill?
+			this->cache->removePrefix("feed:");
 			return Response::redirectTemporarily(this->urlProvider->index());
 		}
 		TemplatePage delPage = this->templ->getPage("page_deletion");

handlers/handlerpageedit.cpp

@@ -101,6 +101,7 @@ Response HandlerPageEdit::handleRequest(PageDao &pageDao, std::string pagename,
 				pageDao.setCategories(pagename, cats);
 				this->database->commitTransaction();
 				this->cache->removePrefix("page:"); // TODO: overkill?
+				this->cache->removePrefix("feed:");
 			}
 			catch(const DatabaseException &e)
 			{