NodeBB/src/controllers/topics.js

'use strict';


var async = require('async');
var nconf = require('nconf');
var winston = require('winston');

var user = require('../user');
var meta = require('../meta');
var topics = require('../topics');
var posts = require('../posts');
var privileges = require('../privileges');
var plugins = require('../plugins');
var helpers = require('./helpers');
var pagination = require('../pagination');
var utils = require('../utils');
var analytics = require('../analytics');

var topicsController = module.exports;

topicsController.get = async function getTopic(req, res, callback) {
	const tid = req.params.topic_id;

	if ((req.params.post_index && !utils.isNumber(req.params.post_index) && req.params.post_index !== 'unread') || !utils.isNumber(tid)) {
		return callback();
	}
	let postIndex = parseInt(req.params.post_index, 10) || 1;
	const [
		userPrivileges,
		settings,
		topicData,
		rssToken,
	] = await Promise.all([
		privileges.topics.get(tid, req.uid),
		user.getSettings(req.uid),
		topics.getTopicData(tid),
		user.auth.getFeedToken(req.uid),
	]);

	var currentPage = parseInt(req.query.page, 10) || 1;
	const pageCount = Math.max(1, Math.ceil((topicData && topicData.postcount) / settings.postsPerPage));
	if (!topicData || userPrivileges.disabled || (settings.usePagination && (currentPage < 1 || currentPage > pageCount))) {
		return callback();
	}

	if (!userPrivileges['topics:read'] || (topicData.deleted && !userPrivileges.view_deleted)) {
		return helpers.notAllowed(req, res);
	}

	if (!res.locals.isAPI && (!req.params.slug || topicData.slug !== tid + '/' + req.params.slug) && (topicData.slug && topicData.slug !== tid + '/')) {
		return helpers.redirect(res, '/topic/' + topicData.slug + (postIndex ? '/' + postIndex : '') + (currentPage > 1 ? '?page=' + currentPage : ''));
	}

	if (postIndex === 'unread') {
		postIndex = await topics.getUserBookmark(tid, req.uid);
	}

	if (utils.isNumber(postIndex) && (postIndex < 1 || postIndex > topicData.postcount)) {
		return helpers.redirect(res, '/topic/' + req.params.topic_id + '/' + req.params.slug + (postIndex > topicData.postcount ? '/' + topicData.postcount : ''));
	}
	postIndex = Math.max(1, postIndex);
	const sort = req.query.sort || settings.topicPostSort;
	const set = sort === 'most_votes' ? 'tid:' + tid + ':posts:votes' : 'tid:' + tid + ':posts';
	const reverse = sort === 'newest_to_oldest' || sort === 'most_votes';
	if (settings.usePagination && !req.query.page) {
		currentPage = calculatePageFromIndex(postIndex, settings);
	}
	const { start, stop } = calculateStartStop(currentPage, postIndex, settings);

	await topics.getTopicWithPosts(topicData, set, req.uid, start, stop, reverse);

	topics.modifyPostsByPrivilege(topicData, userPrivileges);

	const hookData = await plugins.fireHook('filter:controllers.topic.get', { topicData: topicData, uid: req.uid });
	await Promise.all([
		buildBreadcrumbs(hookData.topicData),
		addTags(topicData, req, res),
	]);

	topicData.privileges = userPrivileges;
	topicData.topicStaleDays = meta.config.topicStaleDays;
	topicData['reputation:disabled'] = meta.config['reputation:disabled'];
	topicData['downvote:disabled'] = meta.config['downvote:disabled'];
	topicData['feeds:disableRSS'] = meta.config['feeds:disableRSS'];
	topicData.bookmarkThreshold = meta.config.bookmarkThreshold;
	topicData.postEditDuration = meta.config.postEditDuration;
	topicData.postDeleteDuration = meta.config.postDeleteDuration;
	topicData.scrollToMyPost = settings.scrollToMyPost;
	topicData.allowMultipleBadges = meta.config.allowMultipleBadges === 1;
	topicData.rssFeedUrl = nconf.get('relative_path') + '/topic/' + topicData.tid + '.rss';
	if (req.loggedIn) {
		topicData.rssFeedUrl += '?uid=' + req.uid + '&token=' + rssToken;
	}

	topicData.postIndex = postIndex;
	topicData.pagination = pagination.create(currentPage, pageCount, req.query);
	topicData.pagination.rel.forEach(function (rel) {
		rel.href = nconf.get('url') + '/topic/' + topicData.slug + rel.href;
		res.locals.linkTags.push(rel);
	});

	incrementViewCount(req, tid);

	markAsRead(req, tid);

	analytics.increment(['pageviews:byCid:' + topicData.category.cid]);

	res.render('topic', topicData);
};

function calculatePageFromIndex(postIndex, settings) {
	return 1 + Math.floor((postIndex - 1) / settings.postsPerPage);
}

function calculateStartStop(page, postIndex, settings) {
	var startSkip = 0;

	if (!settings.usePagination) {
		if (postIndex !== 0) {
			page = 1;
		}
		startSkip = Math.max(0, postIndex - Math.ceil(settings.postsPerPage / 2));
	}

	const start = ((page - 1) * settings.postsPerPage) + startSkip;
	const stop = start + settings.postsPerPage - 1;
	return { start: Math.max(0, start), stop: Math.max(0, stop) };
}

function incrementViewCount(req, tid) {
	if (req.uid >= 0) {
		req.session.tids_viewed = req.session.tids_viewed || {};
		if (!req.session.tids_viewed[tid] || req.session.tids_viewed[tid] < Date.now() - 3600000) {
			topics.increaseViewCount(tid);
			req.session.tids_viewed[tid] = Date.now();
		}
	}
}

function markAsRead(req, tid) {
	if (req.loggedIn) {
		topics.markAsRead([tid], req.uid, function (err, markedRead) {
			if (err) {
				return winston.error(err);
			}
			if (markedRead) {
				topics.pushUnreadCount(req.uid);
				topics.markTopicNotificationsRead([tid], req.uid);
			}
		});
	}
}

async function buildBreadcrumbs(topicData) {
	var breadcrumbs = [
		{
			text: topicData.category.name,
			url: nconf.get('relative_path') + '/category/' + topicData.category.slug,
		},
		{
			text: topicData.title,
		},
	];
	const parentCrumbs = await helpers.buildCategoryBreadcrumbs(topicData.category.parentCid);
	topicData.breadcrumbs = parentCrumbs.concat(breadcrumbs);
}

async function addTags(topicData, req, res) {
	var postAtIndex = topicData.posts.find(p => parseInt(p.index, 10) === parseInt(Math.max(0, req.params.post_index - 1), 10));

	var description = '';
	if (postAtIndex && postAtIndex.content) {
		description = utils.stripHTMLTags(utils.decodeHTMLEntities(postAtIndex.content));
	}

	if (description.length > 255) {
		description = description.substr(0, 255) + '...';
	}
	description = description.replace(/\n/g, ' ');

	res.locals.metaTags = [
		{
			name: 'title',
			content: topicData.titleRaw,
		},
		{
			name: 'description',
			content: description,
		},
		{
			property: 'og:title',
			content: topicData.titleRaw,
		},
		{
			property: 'og:description',
			content: description,
		},
		{
			property: 'og:type',
			content: 'article',
		},
		{
			property: 'article:published_time',
			content: utils.toISOString(topicData.timestamp),
		},
		{
			property: 'article:modified_time',
			content: utils.toISOString(topicData.lastposttime),
		},
		{
			property: 'article:section',
			content: topicData.category ? topicData.category.name : '',
		},
	];

	await addOGImageTags(res, topicData, postAtIndex);

	res.locals.linkTags = [
		{
			rel: 'canonical',
			href: nconf.get('url') + '/topic/' + topicData.slug,
		},
	];

	if (!topicData['feeds:disableRSS']) {
		res.locals.linkTags.push({
			rel: 'alternate',
			type: 'application/rss+xml',
			href: topicData.rssFeedUrl,
		});
	}

	if (topicData.category) {
		res.locals.linkTags.push({
			rel: 'up',
			href: nconf.get('url') + '/category/' + topicData.category.slug,
		});
	}
}

async function addOGImageTags(res, topicData, postAtIndex) {
	const uploads = postAtIndex ? await posts.uploads.listWithSizes(postAtIndex.pid) : [];
	const images = uploads.map((upload) => {
		upload.name = nconf.get('url') + nconf.get('upload_url') + '/files/' + upload.name;
		return upload;
	});
	if (topicData.thumb) {
		images.push(topicData.thumb);
	}
	if (topicData.category.backgroundImage && (!postAtIndex || !postAtIndex.index)) {
		images.push(topicData.category.backgroundImage);
	}
	if (postAtIndex && postAtIndex.user && postAtIndex.user.picture) {
		images.push(postAtIndex.user.picture);
	}
	images.forEach(path => addOGImageTag(res, path));
}

function addOGImageTag(res, image) {
	let imageUrl;
	if (typeof image === 'string' && !image.startsWith('http')) {
		imageUrl = nconf.get('url') + image.replace(new RegExp('^' + nconf.get('relative_path')), '');
	} else if (typeof image === 'object') {
		imageUrl = image.name;
	} else {
		imageUrl = image;
	}

	res.locals.metaTags.push({
		property: 'og:image',
		content: imageUrl,
		noEscape: true,
	}, {
		property: 'og:image:url',
		content: imageUrl,
		noEscape: true,
	});

	if (typeof image === 'object' && image.width && image.height) {
		res.locals.metaTags.push({
			property: 'og:image:width',
			content: String(image.width),
		}, {
			property: 'og:image:height',
			content: String(image.height),
		});
	}
}

topicsController.teaser = function (req, res, next) {
	var tid = req.params.topic_id;

	if (!utils.isNumber(tid)) {
		return next();
	}

	async.waterfall([
		function (next) {
			privileges.topics.can('topics:read', tid, req.uid, next);
		},
		function (canRead, next) {
			if (!canRead) {
				return res.status(403).json('[[error:no-privileges]]');
			}
			topics.getLatestUndeletedPid(tid, next);
		},
		function (pid, next) {
			if (!pid) {
				return res.status(404).json('not-found');
			}
			posts.getPostSummaryByPids([pid], req.uid, { stripTags: false }, next);
		},
		function (posts) {
			if (!posts.length) {
				return res.status(404).json('not-found');
			}
			res.json(posts[0]);
		},
	], next);
};

topicsController.pagination = function (req, res, callback) {
	var tid = req.params.topic_id;
	var currentPage = parseInt(req.query.page, 10) || 1;

	if (!utils.isNumber(tid)) {
		return callback();
	}

	async.parallel({
		privileges: async.apply(privileges.topics.get, tid, req.uid),
		settings: async.apply(user.getSettings, req.uid),
		topic: async.apply(topics.getTopicData, tid),
	}, function (err, results) {
		if (err || !results.topic) {
			return callback(err);
		}

		if (!results.privileges.read || (results.topic.deleted && !results.privileges.view_deleted)) {
			return helpers.notAllowed(req, res);
		}

		var postCount = results.topic.postcount;
		var pageCount = Math.max(1, Math.ceil(postCount / results.settings.postsPerPage));

		var paginationData = pagination.create(currentPage, pageCount);
		paginationData.rel.forEach(function (rel) {
			rel.href = nconf.get('url') + '/topic/' + results.topic.slug + rel.href;
		});

		res.json(paginationData);
	});
};