From 807c3eac12b77cdec1d4f97f24d40dfbe0516a07 Mon Sep 17 00:00:00 2001
From: Julian Lam <julian@nodebb.org>
Date: Mon, 6 May 2024 15:14:32 -0400
Subject: [PATCH] feat: on post edit, also target anyone who announced the post
 and their followers

re: #12537
---
 src/api/activitypub.js                 | 16 ++++++++++++----
 src/upgrades/4.0.0/remote_user_urls.js |  4 ++--
 2 files changed, 14 insertions(+), 6 deletions(-)

diff --git a/src/api/activitypub.js b/src/api/activitypub.js
index b91f52277aa6..6af8950c16c6 100644
--- a/src/api/activitypub.js
+++ b/src/api/activitypub.js
@@ -94,13 +94,12 @@ activitypubApi.unfollow = enabledCheck(async (caller, { type, id, actor }) => {
 activitypubApi.create = {};
 
 // this might be better genericised... tbd. some of to/cc is built in mocks.
-async function buildRecipients(object, uid) {
+async function buildRecipients(object, { pid, uid }) {
 	const followers = await db.getSortedSetMembers(`followersRemote:${uid}`);
 	let { to, cc } = object;
 	to = new Set(to);
 	cc = new Set(cc);
 
-
 	// Directly address user if inReplyTo
 	const parentId = await posts.getPostField(object.inReplyTo, 'uid');
 	if (activitypub.helpers.isUri(parentId) && to.has(parentId)) {
@@ -111,6 +110,15 @@ async function buildRecipients(object, uid) {
 	targets.delete(`${nconf.get('url')}/uid/${uid}/followers`); // followers URL not targeted
 	targets.delete(activitypub._constants.publicAddress); // public address not targeted
 
+	// Announcers and their followers
+	if (pid) {
+		const announcers = (await activitypub.notes.announce.list({ pid })).map(({ actor }) => actor);
+		const announcersFollowers = (await user.getUsersFields(announcers, ['followersUrl']))
+			.filter(o => o.hasOwnProperty('followersUrl'))
+			.map(({ followersUrl }) => followersUrl);
+		[...announcers, ...announcersFollowers].forEach(uri => targets.add(uri));
+	}
+
 	object.to = Array.from(to);
 	object.cc = Array.from(cc);
 	return { targets };
@@ -129,7 +137,7 @@ activitypubApi.create.post = enabledCheck(async (caller, { pid }) => {
 	}
 
 	const object = await activitypub.mocks.note(post);
-	const { targets } = await buildRecipients(object, post.user.uid);
+	const { targets } = await buildRecipients(object, { uid: post.user.uid });
 	const { cid } = post.category;
 	const followers = await activitypub.notes.getCategoryFollowers(cid);
 
@@ -175,7 +183,7 @@ activitypubApi.update.profile = enabledCheck(async (caller, { uid }) => {
 
 activitypubApi.update.note = enabledCheck(async (caller, { post }) => {
 	const object = await activitypub.mocks.note(post);
-	const { targets } = await buildRecipients(object, post.user.uid);
+	const { targets } = await buildRecipients(object, { pid: post.pid, uid: post.user.uid });
 
 	const allowed = await privileges.posts.can('topics:read', post.pid, activitypub._constants.uid);
 	if (!allowed) {
diff --git a/src/upgrades/4.0.0/remote_user_urls.js b/src/upgrades/4.0.0/remote_user_urls.js
index 9a9aa8b8a30e..9c4a1a192467 100644
--- a/src/upgrades/4.0.0/remote_user_urls.js
+++ b/src/upgrades/4.0.0/remote_user_urls.js
@@ -15,8 +15,8 @@ module.exports = {
 
 		let actorIds = await db.getSortedSetMembers('usersRemote:lastCrawled');
 		progress.total = actorIds.length;
-		const exists = await Promise.all(actorIds.map(async id => await db.isObjectField(`userRemote:${id}`, 'url')));
-		actorIds = actorIds.filter((id, idx) => !exists[idx]);
+		const exists = await Promise.all(actorIds.map(async id => await db.isObjectFields(`userRemote:${id}`, ['url', 'followersUrl'])));
+		actorIds = actorIds.filter((id, idx) => !exists[idx].every(Boolean));
 
 		// Increment ones that were already completed
 		progress.incr(progress.total - actorIds.length);