create an isUserBanned utility function

src/utils/checkBan.ts

@@ -0,0 +1,27 @@
+import { HashedUserID } from "../types/user.model";
+import { db } from "../databases/databases";
+import { Category, HashedIP } from "../types/segments.model";
+import { banUser } from "../routes/shadowBanUser";
+import { config } from "../config";
+import { Logger } from "./logger";
+
+export async function isUserBanned(userID: HashedUserID): Promise<boolean> {
+    return (await db.prepare("get", `SELECT 1 FROM "shadowBannedUsers" WHERE "userID" = ? LIMIT 1`, [userID], { useReplica: true })) !== undefined;
+}
+
+export async function isIPBanned(ip: HashedIP): Promise<boolean> {
+    return (await db.prepare("get", `SELECT 1 FROM "shadowBannedIPs" WHERE "hashedIP" = ? LIMIT 1`, [ip], { useReplica: true })) !== undefined;
+}
+
+// NOTE: this function will propagate IP bans
+export async function checkBanStatus(userID: HashedUserID, ip: HashedIP): Promise<boolean> {
+    const userBanStatus = await isUserBanned(userID);
+    const ipBanStatus = await isIPBanned(ip);
+
+    if (!userBanStatus && ipBanStatus) {
+        // Make sure the whole user is banned
+        banUser(userID, true, true, 1, config.categoryList as Category[], config.deArrowTypes)
+            .catch((e) => Logger.error(`Error banning user after submitting from a banned IP: ${e}`));
+    }
+    return userBanStatus || ipBanStatus;
+}