feat: support remote Dislike activity, federate out a Dislike on downvote, bwahahah

src/activitypub/inbox.js

@@ -352,6 +352,26 @@ inbox.like = async (req) => {
 	socketHelpers.upvote(result, 'notifications:upvoted-your-post-in');
 };
 
+inbox.dislike = async (req) => {
+	const { actor, object } = req.body;
+	const { type, id } = await activitypub.helpers.resolveLocalId(object.id);
+
+	if (type !== 'post' || !(await posts.exists(id))) {
+		return reject('Dislike', object, actor);
+	}
+
+	const allowed = await privileges.posts.can('posts:downvote', id, activitypub._constants.uid);
+	if (!allowed) {
+		activitypub.helpers.log(`[activitypub/inbox.like] ${id} not allowed to be downvoted.`);
+		return reject('Dislike', object, actor);
+	}
+
+	activitypub.helpers.log(`[activitypub/inbox/dislike] id ${id} via ${actor}`);
+
+	await posts.downvote(id, actor);
+	await activitypub.feps.announce(object.id, req.body);
+};
+
 inbox.announce = async (req) => {
 	let { actor, object, published, to, cc } = req.body;
 	activitypub.helpers.log(`[activitypub/inbox/announce] Parsing Announce(${object.type}) from ${actor}`);

src/activitypub/out.js

@@ -277,6 +277,32 @@ Out.like.note = enabledCheck(async (uid, pid) => {
 	]);
 });
 
+Out.dislike = {};
+
+Out.dislike.note = enabledCheck(async (uid, pid) => {
+	const payload = {
+		id: `${nconf.get('url')}/uid/${uid}#activity/dislike/${encodeURIComponent(pid)}`,
+		type: 'Dislike',
+		actor: `${nconf.get('url')}/uid/${uid}`,
+		object: utils.isNumber(pid) ? `${nconf.get('url')}/post/${pid}` : pid,
+	};
+
+	if (!activitypub.helpers.isUri(pid)) { // only 1b12 announce for local likes
+		await activitypub.feps.announce(pid, payload);
+		return;
+	}
+
+	const recipient = await posts.getPostField(pid, 'uid');
+	if (!activitypub.helpers.isUri(recipient)) {
+		return;
+	}
+
+	await Promise.all([
+		activitypub.send('uid', uid, [recipient], payload),
+		activitypub.feps.announce(pid, payload),
+	]);
+});
+
 Out.announce = {};
 
 Out.announce.topic = enabledCheck(async (tid) => {

src/api/helpers.js

@@ -147,14 +147,34 @@ async function executeCommand(caller, command, eventName, notification, data) {
 		websockets.in(`uid_${caller.uid}`).emit(`posts.${command}`, result);
 		websockets.in(data.room_id).emit(`event:${eventName}`, result);
 	}
-	if (result && command === 'upvote') {
-		socketHelpers.upvote(result, notification);
-		await activitypub.out.like.note(caller.uid, data.pid);
-	} else if (result && notification) {
-		socketHelpers.sendNotificationToPostOwner(data.pid, caller.uid, command, notification);
-	} else if (result && command === 'unvote') {
-		socketHelpers.rescindUpvoteNotification(data.pid, caller.uid);
-		await activitypub.out.undo.like(caller.uid, data.pid);
+
+	if (result) {
+		switch (command) {
+			case 'upvote': {
+				socketHelpers.upvote(result, notification);
+				await activitypub.out.like.note(caller.uid, data.pid);
+				break;
+			}
+
+			case 'downvote': {
+				await activitypub.out.dislike.note(caller.uid, data.pid);
+				break;
+			}
+
+			case 'unvote': {
+				socketHelpers.rescindUpvoteNotification(data.pid, caller.uid);
+				await activitypub.out.undo.like(caller.uid, data.pid);
+				break;
+			}
+
+			default: {
+				if (notification) {
+					socketHelpers.sendNotificationToPostOwner(data.pid, caller.uid, command, notification);
+				}
+				break;
+			}
+		}
 	}
+
 	return result;
 }