feat: changes to how a topic is presented via ActivityPub; conformance with upcoming changes to 7888

src/activitypub/contexts.js

@@ -12,6 +12,7 @@ const acceptableTypes = ['Collection', 'CollectionPage', 'OrderedCollection', 'O
 Contexts.get = async (uid, id) => {
 	let context;
 	let type;
+	let collection;
 
 	// Generate digest for If-None-Match if locally cached
 	const tid = await posts.getPostField(id, 'tid');
@@ -27,12 +28,15 @@ Contexts.get = async (uid, id) => {
 	}
 
 	try {
-		({ context } = await activitypub.get('uid', uid, id, { headers }));
+		({ id, type, context, posts: collection } = await activitypub.get('uid', uid, id, { headers }));
-		if (!context) {
+		if (type === 'Conversation' && collection) {
+			activitypub.helpers.log(`[activitypub/context] ${id} is the context.`);
+			return { context: id, collection };
+		} else if (!context) {
 			activitypub.helpers.log(`[activitypub/context] ${id} contains no context.`);
 			return false;
 		}
-		({ type } = await activitypub.get('uid', uid, context));
+		({ type, posts: collection } = await activitypub.get('uid', uid, context));
 	} catch (e) {
 		if (e.code === 'ap_get_304') {
 			activitypub.helpers.log(`[activitypub/context] ${id} context unchanged.`);
@@ -43,8 +47,8 @@ Contexts.get = async (uid, id) => {
 		return false;
 	}
 
-	if (acceptableTypes.includes(type)) {
+	if (type === 'Conversation') {
-		return { context };
+		return { context, collection };
 	}
 
 	return false;
@@ -98,9 +102,13 @@ Contexts.getItems = async (uid, id, options) => {
 	const inputId = activitypub.helpers.isUri(options.input) ? options.input : options.input.id;
 	const inCollection = Array.from(chain).map(p => p.pid).includes(inputId);
 	if (!inCollection) {
-		chain.add(activitypub.helpers.isUri(options.input) ?
+		const item = activitypub.helpers.isUri(options.input) ?
 			await parseString(uid, options.input) :
-			await parseItem(uid, options.input));
+			await parseItem(uid, options.input);
+
+		if (item) {
+			chain.add(item);
+		}
 	}
 
 	return chain;

src/activitypub/notes.js

@@ -49,7 +49,7 @@ Notes.assert = async (uid, input, options = { skipChecks: false }) => {
 		const { tid } = context;
 		return { tid, count: 0 };
 	} else if (context.context) {
-		chain = Array.from(await activitypub.contexts.getItems(uid, context.context, { input }));
+		chain = Array.from(await activitypub.contexts.getItems(uid, context.collection, { input }));
 		if (chain && chain.length) {
 			// Context resolves, use in later topic creation
 			context = context.context;

src/controllers/activitypub/actors.js

@@ -115,12 +115,52 @@ Actors.replies = async function (req, res) {
 Actors.topic = async function (req, res, next) {
 	const allowed = await privileges.topics.can('topics:read', req.params.tid, activitypub._constants.uid);
 	if (!allowed) {
-		return res.sendStatus(404);
+		return next();
+	}
+
+	const { cid, titleRaw: name, mainPid, slug } = await topics.getTopicFields(req.params.tid, ['cid', 'title', 'mainPid', 'slug']);
+	let pids = await db.getSortedSetMembers(`tid:${req.params.tid}:posts`);
+	pids.push(mainPid);
+	pids = pids.map(pid => (utils.isNumber(pid) ? `${nconf.get('url')}/post/${pid}` : pid));
+
+	// Generate digest for ETag
+	const digest = activitypub.helpers.generateDigest(new Set(pids));
+	const ifNoneMatch = (req.get('If-None-Match') || '').split(',').map((tag) => {
+		tag = tag.trim();
+		if (tag.startsWith('"') && tag.endsWith('"')) {
+			return tag.slice(1, tag.length - 1);
+		}
+
+		return tag;
+	});
+	if (ifNoneMatch.includes(digest)) {
+		return res.sendStatus(304);
+	}
+	res.set('ETag', digest);
+
+	const object = {
+		'@context': 'https://www.w3.org/ns/activitystreams',
+		id: `${nconf.get('url')}/topic/${req.params.tid}`,
+		url: `${nconf.get('url')}/topic/${slug}`,
+		type: 'Conversation',
+		name,
+		attributedTo: `${nconf.get('url')}/category/${cid}`,
+		// audience: cid !== -1 ? `${nconf.get('url')}/category/${cid}` : undefined,
+		posts: `${nconf.get('url')}/topic/${req.params.tid}/posts`,
+	};
+
+	res.status(200).json(object);
+};
+
+Actors.topicPosts = async function (req, res, next) {
+	const allowed = await privileges.topics.can('topics:read', req.params.tid, activitypub._constants.uid);
+	if (!allowed) {
+		return next();
 	}
 
 	const page = parseInt(req.query.page, 10) || undefined;
 	const perPage = meta.config.postsPerPage;
-	const { cid, titleRaw: name, mainPid, slug } = await topics.getTopicFields(req.params.tid, ['cid', 'title', 'mainPid', 'slug']);
+	const mainPid = await topics.getTopicField(req.params.tid, 'mainPid');
 	try {
 		let [collection, pids] = await Promise.all([
 			activitypub.helpers.generateCollection({
@@ -136,21 +176,6 @@ Actors.topic = async function (req, res, next) {
 		pids = pids.map(pid => (utils.isNumber(pid) ? `${nconf.get('url')}/post/${pid}` : pid));
 		collection.totalItems += 1; // account for mainPid
 
-		// Generate digest for ETag
-		const digest = activitypub.helpers.generateDigest(new Set(pids));
-		const ifNoneMatch = (req.get('If-None-Match') || '').split(',').map((tag) => {
-			tag = tag.trim();
-			if (tag.startsWith('"') && tag.endsWith('"')) {
-				return tag.slice(1, tag.length - 1);
-			}
-
-			return tag;
-		});
-		if (ifNoneMatch.includes(digest)) {
-			return res.sendStatus(304);
-		}
-		res.set('ETag', digest);
-
 		// Convert pids to urls
 		if (page || collection.totalItems < meta.config.postsPerPage) {
 			collection.orderedItems = collection.orderedItems || [];
@@ -162,11 +187,7 @@ Actors.topic = async function (req, res, next) {
 
 		const object = {
 			'@context': 'https://www.w3.org/ns/activitystreams',
-			id: `${nconf.get('url')}/topic/${req.params.tid}${collection.orderedItems && page ? `?page=${page}` : ''}`,
+			id: `${nconf.get('url')}/topic/${req.params.tid}/posts${collection.orderedItems && page ? `?page=${page}` : ''}`,
-			url: `${nconf.get('url')}/topic/${slug}`,
-			name,
-			attributedTo: `${nconf.get('url')}/category/${cid}`,
-			audience: cid !== -1 ? `${nconf.get('url')}/category/${cid}` : undefined,
 			...collection,
 		};
 

src/routes/activitypub.js

@@ -40,13 +40,14 @@ module.exports = function (app, middleware, controllers) {
 	app.get('/post/:pid', [...middlewares, middleware.assert.post], controllers.activitypub.actors.note);
 	app.get('/post/:pid/replies', [...middlewares, middleware.assert.post], controllers.activitypub.actors.replies);
 
+	app.get('/topic/:tid/posts', [...middlewares, middleware.assert.topic], controllers.activitypub.actors.topicPosts);
 	app.get('/topic/:tid/:slug?', [...middlewares, middleware.assert.topic], controllers.activitypub.actors.topic);
 
-	app.get('/category/:cid/:slug?', [...middlewares, middleware.assert.category], controllers.activitypub.actors.category);
 	app.get('/category/:cid/inbox', [...middlewares, middleware.assert.category], controllers.activitypub.getInbox);
 	app.post('/category/:cid/inbox', [...inboxMiddlewares, middleware.assert.category, ...inboxMiddlewares], controllers.activitypub.postInbox);
 	app.get('/category/:cid/outbox', [...middlewares, middleware.assert.category], controllers.activitypub.getCategoryOutbox);
 	app.post('/category/:cid/outbox', [...middlewares, middleware.assert.category], controllers.activitypub.postOutbox);
+	app.get('/category/:cid/:slug?', [...middlewares, middleware.assert.category], controllers.activitypub.actors.category);
 
 	app.get('/message/:mid', [...middlewares, middleware.assert.message], controllers.activitypub.actors.message);
 };