From c7040b77b5c53f72e8b3d1e4ad57c32499768880 Mon Sep 17 00:00:00 2001
From: Namekuji <nmkj@waah.day>
Date: Thu, 27 Jul 2023 07:15:58 -0400
Subject: [PATCH] export visibility check

---
 packages/backend/src/db/scylla.ts             | 28 ++++++++++++++++++-
 .../backend/src/server/api/common/getters.ts  | 28 +++++--------------
 packages/backend/src/services/user-cache.ts   |  4 +++
 3 files changed, 38 insertions(+), 22 deletions(-)

diff --git a/packages/backend/src/db/scylla.ts b/packages/backend/src/db/scylla.ts
index dbd1cd2d2d..bc9d688397 100644
--- a/packages/backend/src/db/scylla.ts
+++ b/packages/backend/src/db/scylla.ts
@@ -3,7 +3,8 @@ import type { PopulatedEmoji } from "@/misc/populate-emojis.js";
 import type { Note } from "@/models/entities/note.js";
 import type { NoteReaction } from "@/models/entities/note-reaction.js";
 import { Client, types } from "cassandra-driver";
-import { noteVisibilities } from "@/types.js";
+import type { User } from "@/models/entities/user.js";
+import { LocalFollowingsCache } from "@/misc/cache.js";
 
 function newClient(): Client | null {
 	if (!config.scylla) {
@@ -182,3 +183,28 @@ export function parseScyllaReaction(row: types.Row): ScyllaNoteReaction {
 		emoji: row.get("emoji"),
 	};
 }
+
+export async function isVisible(
+	note: ScyllaNote,
+	user: { id: User["id"] } | null,
+): Promise<boolean> {
+	let visible = false;
+
+	if (
+		["public", "home"].includes(note.visibility) // public post
+	) {
+		visible = true;
+	} else if (user) {
+		const cache = await LocalFollowingsCache.init(user.id);
+
+		visible =
+			note.userId === user.id || // my own post
+			note.visibleUserIds.includes(user.id) || // visible to me
+			note.mentions.includes(user.id) || // mentioned me
+			(note.visibility === "followers" &&
+				(await cache.isFollowing(note.userId))) || // following
+			note.replyUserId === user.id; // replied to myself
+	}
+
+	return visible;
+}
diff --git a/packages/backend/src/server/api/common/getters.ts b/packages/backend/src/server/api/common/getters.ts
index b3259d2035..b873914294 100644
--- a/packages/backend/src/server/api/common/getters.ts
+++ b/packages/backend/src/server/api/common/getters.ts
@@ -3,8 +3,12 @@ import type { User } from "@/models/entities/user.js";
 import type { Note } from "@/models/entities/note.js";
 import { Notes, Users } from "@/models/index.js";
 import { generateVisibilityQuery } from "./generate-visibility-query.js";
-import { parseScyllaNote, prepared, scyllaClient } from "@/db/scylla.js";
-import { LocalFollowingsCache } from "@/misc/cache.js";
+import {
+	isVisible,
+	parseScyllaNote,
+	prepared,
+	scyllaClient,
+} from "@/db/scylla.js";
 
 /**
  * Get note for API processing, taking into account visibility.
@@ -22,25 +26,7 @@ export async function getNote(
 		);
 		if (result.rowLength > 0) {
 			const candidate = parseScyllaNote(result.first());
-			let valid = false;
-
-			if (
-				["public", "home"].includes(candidate.visibility) // public post
-			) {
-				valid = true;
-			} else if (me) {
-				const cache = await LocalFollowingsCache.init(me.id);
-
-				valid =
-					candidate.userId === me.id || // my own post
-					candidate.visibleUserIds.includes(me.id) || // visible to me
-					candidate.mentions.includes(me.id) || // mentioned me
-					(candidate.visibility === "followers" &&
-						(await cache.isFollowing(candidate.userId))) || // following
-					candidate.replyUserId === me.id; // replied to myself
-			}
-
-			if (valid) {
+			if (await isVisible(candidate, me)) {
 				note = candidate;
 			}
 		}
diff --git a/packages/backend/src/services/user-cache.ts b/packages/backend/src/services/user-cache.ts
index ed700185df..2eff8ba11f 100644
--- a/packages/backend/src/services/user-cache.ts
+++ b/packages/backend/src/services/user-cache.ts
@@ -20,6 +20,10 @@ export const uriPersonCache = new Cache<CacheableUser | null>(
 	"uriPerson",
 	60 * 30,
 );
+export const userDenormalizedCache = new Cache<CacheableUser>(
+	"userDenormalized",
+	60 * 30,
+);
 
 subscriber.on("message", async (_, data) => {
 	const obj = JSON.parse(data);