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handlers/handlerpageview.cpp

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+/* Copyright (c) 2018 Albert S.
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in all
+copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+SOFTWARE.
+*/
+#include "handlerpageview.h"
+#include "../database/exceptions.h"
+#include "../logger.h"
+#include "../parser.h"
+#include "../htmllink.h"
+
+bool HandlerPageView::canAccess(std::string page)
+{
+	return this->userSession->user.permissions.canRead();
+}
+
+std::string HandlerPageView::createIndexContent(IParser &parser, std::string content)
+{
+	std::vector<Headline> headlines = parser.extractHeadlines(content);
+	std::string indexcontent = "";
+	unsigned int l = 0;
+	for(const Headline &h : headlines)
+	{
+		if(h.level > l)
+		{
+			indexcontent += "<ul>";
+		}
+		else if(h.level < l)
+		{
+			indexcontent += "</ul>";
+		}
+		l = h.level;
+		HtmlLink link;
+		link.href = "#" + h.title;
+		link.innervalue = h.title;
+		link.cssclass = "indexlink";
+		indexcontent += "<li>" + link.render() + "</li>";
+	}
+	indexcontent += "</ul>";
+	return indexcontent;
+}
+
+Response HandlerPageView::handleRequest(PageDao &pageDao, std::string pagename, const Request &r)
+{
+
+	std::string revisionparam = r.get("revision");
+	unsigned int revisionid = 0;
+	if(!revisionparam.empty())
+	{
+		try
+		{
+			revisionid = utils::toUInt(revisionparam);
+		}
+		catch(const std::exception &e)
+		{
+			return errorResponse("Error", "Supplied revisionid is misformated");
+		}
+	}
+
+	std::optional<Revision> revision;
+	std::string templatepartname;
+	try
+	{
+		if(revisionid > 0)
+		{
+			revision = this->database->createRevisionDao()->getRevisionForPage(pagename, revisionid);
+			if(!revision)
+			{
+				return errorResponse("Revision not found", "No such revision found");
+			}
+			templatepartname = "page_view_revision";
+		}
+		else
+		{
+			if(!this->userSession->loggedIn)
+			{
+				auto content = this->cache->get("page:foranon:" + pagename);
+				if(content)
+				{
+					Response r;
+					r.setBody(*content);
+					// TODO: etag?
+					return r;
+				}
+			}
+			revision = this->database->createRevisionDao()->getCurrentForPage(pagename);
+			templatepartname = "page_view";
+		}
+	}
+	catch(const DatabaseException &e)
+	{
+		Logger::error() << "DatabaseException in handlerpageview: " << e.what();
+		return errorResponse("Database error", "While trying to fetch revision, a database error occured");
+	}
+
+	TemplatePage &page = this->templ->getPage(templatepartname);
+
+	Parser parser;
+	Response result;
+	result.setStatus(200);
+	std::string indexcontent;
+	std::string parsedcontent;
+
+	if(revisionid > 0)
+	{
+		indexcontent = createIndexContent(parser, revision->content);
+		parsedcontent = parser.parse(pageDao, *this->urlProvider, revision->content);
+	}
+	else
+	{
+		std::string cachekeyindexcontent = "page:indexcontent:" + pagename;
+		std::string cachekeyparsedcontent = "page:parsedcontent:" + pagename;
+		auto cachedindexcontent = this->cache->get(cachekeyindexcontent);
+		auto cachedparsedcontent = this->cache->get(cachekeyparsedcontent);
+		if(cachedindexcontent)
+		{
+			indexcontent = *cachedindexcontent;
+		}
+		else
+		{
+			indexcontent = createIndexContent(parser, revision->content);
+			this->cache->put(cachekeyindexcontent, indexcontent);
+		}
+		if(cachedparsedcontent)
+		{
+			parsedcontent = *cachedparsedcontent;
+		}
+		else
+		{
+			parsedcontent = parser.parse(pageDao, *this->urlProvider, revision->content);
+			this->cache->put(cachekeyparsedcontent, parsedcontent);
+		}
+	}
+	page.setVar("content", parsedcontent);
+	page.setVar("index", indexcontent);
+	page.setVar("editedby", revision->author);
+	page.setVar("editedon", utils::toISODate(revision->timestamp));
+	page.setVar("historyurl", this->urlProvider->pageHistory(pagename));
+	page.setVar("revision", revisionparam);
+	setPageVars(page, pagename);
+	std::string body = page.render();
+	if(revisionid == 0 && !this->userSession->loggedIn)
+	{
+		this->cache->put("page:foranon:" + pagename, body);
+	}
+	result.addHeader("ETAG", std::to_string(revision->revision) + "+" + std::to_string(this->userSession->loggedIn));
+	result.setBody(body);
+	return result;
+}