From 462032a4e986b410faa91adb95eaf3bcf4bd4cd6 Mon Sep 17 00:00:00 2001
From: Bulat Kurbanov <kurbanovbul@gmail.com>
Date: Sat, 6 Aug 2022 20:43:52 +0300
Subject: [PATCH] Add limiter

---
 src/bots/factory/bots/approved/annotations.ts |  5 +-
 src/bots/factory/bots/approved/index.ts       |  9 +++-
 .../bots/approved/services/book_library.ts    |  2 +-
 src/bots/limiter/index.ts                     | 46 +++++++++++++++++++
 4 files changed, 57 insertions(+), 5 deletions(-)
 create mode 100644 src/bots/limiter/index.ts

diff --git a/src/bots/factory/bots/approved/annotations.ts b/src/bots/factory/bots/approved/annotations.ts
index f43ffee..7893d84 100644
--- a/src/bots/factory/bots/approved/annotations.ts
+++ b/src/bots/factory/bots/approved/annotations.ts
@@ -1,5 +1,5 @@
 import { Context } from "telegraf";
-import { AuthorAnnnotation, BookAnnotation } from "./services/book_library";
+import { AuthorAnnotation, BookAnnotation } from "./services/book_library";
 
 import { isNormalText } from "./utils";
 import { getTextPaginationData } from './keyboard';
@@ -7,7 +7,7 @@ import Sentry from '@/sentry';
 import { downloadImage } from "./services/downloader";
 
 
-export function getAnnotationHandler<T extends BookAnnotation | AuthorAnnnotation>(
+export function getAnnotationHandler<T extends BookAnnotation | AuthorAnnotation>(
     annotationGetter: (id: number) => Promise<T>,
     callbackData: string
 ): (ctx: Context) => Promise<void> {
@@ -32,7 +32,6 @@ export function getAnnotationHandler<T extends BookAnnotation | AuthorAnnnotatio
                 try {
                     await ctx.telegram.sendPhoto(ctx.message.chat.id, { source: imageData });
                 } catch (e) {
-                    console.log(e);
                     Sentry.captureException(e);
                 }
             }
diff --git a/src/bots/factory/bots/approved/index.ts b/src/bots/factory/bots/approved/index.ts
index 8b6ece7..eaafb10 100644
--- a/src/bots/factory/bots/approved/index.ts
+++ b/src/bots/factory/bots/approved/index.ts
@@ -12,6 +12,7 @@ import * as CallbackData from "./callback_data";
 import * as BookLibrary from "./services/book_library";
 import * as Rating from "./services/book_ratings";
 import UsersCounter from '@/analytics/users_counter';
+import Limiter from '@/bots/limiter';
 import { createOrUpdateUserSettings, getUserOrDefaultLangCodes } from './services/user_settings';
 import { formatBook, formatBookShort, formatAuthor, formatSequence, formatTranslator, formatDetailBook, formatDetailBookWithRating } from './format';
 import { getCallbackArgs, getPaginatedMessage, getPrefixWithQueryCreator, getSearchArgs, registerLanguageSettingsCallback, registerPaginationCommand, registerRandomItemCallback } from './utils';
@@ -54,6 +55,12 @@ export async function createApprovedBot(token: string, state: BotState): Promise
         await next();
     });
 
+    bot.use(async (ctx: Context, next) => {
+        if (await Limiter.isLimited(ctx.update.update_id)) return;
+
+        await next();
+    });
+
     bot.command(["start", `start@${me.username}`], async (ctx: Context) => {
         if (!ctx.message) {
             return;
@@ -449,7 +456,7 @@ export async function createApprovedBot(token: string, state: BotState): Promise
     });
 
     bot.catch((err, ctx: Context) => {
-        console.log(err, ctx);
+        console.log({err, ctx});
         Sentry.captureException(err);
     });
 
diff --git a/src/bots/factory/bots/approved/services/book_library.ts b/src/bots/factory/bots/approved/services/book_library.ts
index c7d4f14..e6664a8 100644
--- a/src/bots/factory/bots/approved/services/book_library.ts
+++ b/src/bots/factory/bots/approved/services/book_library.ts
@@ -88,7 +88,7 @@ export interface Sequence {
 }
 
 
-export interface AuthorAnnnotation {
+export interface AuthorAnnotation {
     id: number;
     title: string;
     text: string;
diff --git a/src/bots/limiter/index.ts b/src/bots/limiter/index.ts
new file mode 100644
index 0000000..57a3513
--- /dev/null
+++ b/src/bots/limiter/index.ts
@@ -0,0 +1,46 @@
+import { createClient, RedisClientType } from 'redis';
+
+import env from '@/config';
+
+import Sentry from '@/sentry';
+
+
+export default class Limiter {
+    static MAX_PROCESSING_COUNT: number = 3;
+    static _redisClient: RedisClientType | null = null;
+
+    static async _getClient() {
+        if (this._redisClient === null) {
+            this._redisClient = createClient({
+                url: `redis://${env.REDIS_HOST}:${env.REDIS_PORT}/${env.REDIS_DB}`
+            });
+
+            this._redisClient.on('error', (err) => {
+                console.log(err);
+                Sentry.captureException(err);
+            });
+
+            await this._redisClient.connect();
+        }
+
+        return this._redisClient;
+    }
+
+    static _getKey(updateId: number) {
+        return `update_${updateId}`;
+    }
+
+    static async _getCount(updateId: number): Promise<number> {
+        const key = this._getKey(updateId);
+        
+        const client = await this._getClient();
+
+        await client.set(key, 0, {EX: 5 * 60, NX: true});
+        return client.incr(key);
+    }
+
+    static async isLimited(updateId: number): Promise<boolean> {
+        const count = await this._getCount(updateId);
+        return count <= this.MAX_PROCESSING_COUNT;
+    }
+}