translator: add daily translation quota for deepl (#1275)

apps/readest-app/src/app/reader/components/annotator/TranslatorPopup.tsx

@@ -98,7 +98,7 @@ const TranslatorPopup: React.FC<TranslatorPopupProps> = ({
       setTranslation(null);
 
       try {
-        const input = text.replaceAll('\n', ' ').trim();
+        const input = text.replaceAll('\n', '').trim();
         const result = await translate([input]);
         const translatedText = result[0];
         const detectedSource = null;

apps/readest-app/src/hooks/useTranslator.ts

@@ -65,7 +65,7 @@ export function useTranslator({
           ),
         );
 
-        return results;
+        return enablePolishing ? polish(results, targetLanguage) : results;
       }
 
       setLoading(true);

apps/readest-app/src/pages/api/deepl/translate.ts

@@ -2,11 +2,18 @@ import crypto from 'crypto';
 import { NextApiRequest, NextApiResponse } from 'next';
 import { corsAllMethods, runMiddleware } from '@/utils/cors';
 import { supabase } from '@/utils/supabase';
-import { getUserPlan } from '@/utils/access';
+import { getDailyTranslationPlanData, getUserPlan } from '@/utils/access';
 
 const DEFAULT_DEEPL_FREE_API = 'https://api-free.deepl.com/v2/translate';
 const DEFAULT_DEEPL_PRO_API = 'https://api.deepl.com/v2/translate';
 
+const ErrorCodes = {
+  UNAUTHORIZED: 'Unauthorized',
+  DEEPL_API_ERROR: 'DeepL API Error',
+  DAILY_QUOTA_EXCEEDED: 'Daily Quota Exceeded',
+  INTERNAL_SERVER_ERROR: 'Internal Server Error',
+};
+
 interface KVNamespace {
   get(key: string): Promise<string | null>;
   put(key: string, value: string, options?: { expirationTtl?: number }): Promise<void>;
@@ -101,7 +108,11 @@ const handler = async (req: NextApiRequest, res: NextApiResponse) => {
           }
         }
 
+        // if (!user || !token) return res.status(401).json({ error: ErrorCodes.UNAUTHORIZED });
+
         return await callDeepLAPI(
+          user?.id,
+          token,
           singleText,
           sourceLang,
           targetLang,
@@ -115,11 +126,16 @@ const handler = async (req: NextApiRequest, res: NextApiResponse) => {
     return res.status(200).json({ translations });
   } catch (error) {
     console.error('Error proxying DeepL request:', error);
-    return res.status(500).json({ error: 'Internal Server Error' });
+    if (error instanceof Error && error.message.includes(ErrorCodes.DAILY_QUOTA_EXCEEDED)) {
+      return res.status(429).json({ error: ErrorCodes.DAILY_QUOTA_EXCEEDED });
+    }
+    return res.status(500).json({ error: ErrorCodes.INTERNAL_SERVER_ERROR });
   }
 };
 
 async function callDeepLAPI(
+  userId: string | undefined,
+  token: string | undefined,
   text: string,
   sourceLang: string,
   targetLang: string,
@@ -128,11 +144,22 @@ async function callDeepLAPI(
   translationsKV: KVNamespace | undefined,
   useCache: boolean,
 ) {
+  let dailyUsageKey = '';
+  if (userId && token) {
+    const { quota: dailyQuota } = getDailyTranslationPlanData(token);
+    const currentDate = new Date().toISOString().split('T')[0]!;
+    dailyUsageKey = `daily_usage:${currentDate}:${userId}`;
+    const dailyUsage = (await translationsKV?.get(dailyUsageKey)) || '0';
+    if (dailyQuota <= parseInt(dailyUsage) + text.length) {
+      throw new Error(ErrorCodes.DAILY_QUOTA_EXCEEDED);
+    }
+  }
+
   const isV2Api = apiUrl.endsWith('/v2/translate');
 
   // TODO: this should be processed in the client, but for now, we need to do it here
   // please remove this when most clients are updated
-  const input = text.replaceAll('\n', ' ').trim();
+  const input = text.replaceAll('\n', '').trim();
   const requestBody = {
     text: isV2Api ? [input] : input,
     source_lang: isV2Api ? sourceLang : (LANG_V2_V1_MAP[sourceLang] ?? sourceLang),
@@ -166,6 +193,20 @@ async function callDeepLAPI(
     translatedText = data.data;
   }
 
+  let newDailyUsage = 0;
+  if (dailyUsageKey && translationsKV) {
+    try {
+      const usage = translatedText.length + text.length;
+      const dailyUsage = (await translationsKV.get(dailyUsageKey)) || '0';
+      newDailyUsage = parseInt(dailyUsage) + usage;
+      await translationsKV.put(dailyUsageKey, newDailyUsage.toString(), {
+        expirationTtl: 86400 * 30,
+      });
+    } catch (cacheError) {
+      console.error('Cache storage error:', cacheError);
+    }
+  }
+
   if (useCache && translationsKV && translatedText) {
     try {
       const cacheKey = generateCacheKey(text, sourceLang, targetLang);
@@ -177,6 +218,7 @@ async function callDeepLAPI(
 
   return {
     text: translatedText,
+    daily_usage: newDailyUsage,
     detected_source_language: detectedSourceLanguage,
   };
 }

apps/readest-app/src/services/constants.ts

@@ -11,7 +11,7 @@ import {
   ViewSettings,
 } from '@/types/book';
 import { ReadSettings, SystemSettings } from '@/types/settings';
-import { UserStorageQuota } from '@/types/user';
+import { UserStorageQuota, UserDailyTranslationQuota } from '@/types/user';
 import { getDefaultMaxBlockSize, getDefaultMaxInlineSize } from '@/utils/config';
 import { stubTranslation as _ } from '@/utils/misc';
 
@@ -527,6 +527,12 @@ export const DEFAULT_STORAGE_QUOTA: UserStorageQuota = {
   pro: 10 * 1024 * 1024 * 1024,
 };
 
+export const DEFAULT_DAILY_TRANSLATION_QUOTA: UserDailyTranslationQuota = {
+  free: 100 * 1024,
+  plus: 1 * 1024 * 1024,
+  pro: 10 * 1024 * 1024,
+};
+
 export const DOUBLE_CLICK_INTERVAL_THRESHOLD_MS = 250;
 export const DISABLE_DOUBLE_CLICK_ON_MOBILE = true;
 export const LONG_HOLD_THRESHOLD = 500;

apps/readest-app/src/types/user.ts

@@ -1,10 +1,12 @@
-export type UserStorageQuota = {
+export interface UserQuota {
   free: number;
   plus: number;
   pro: number;
-};
+}
 
-export type UserPlan = keyof UserStorageQuota;
+export type UserPlan = keyof UserQuota;
+export type UserStorageQuota = UserQuota;
+export type UserDailyTranslationQuota = UserQuota;
 
 export type QuotaType = {
   name: string;

apps/readest-app/src/utils/access.ts

@@ -1,6 +1,6 @@
 import { jwtDecode } from 'jwt-decode';
 import { UserPlan } from '@/types/user';
-import { DEFAULT_STORAGE_QUOTA } from '@/services/constants';
+import { DEFAULT_DAILY_TRANSLATION_QUOTA, DEFAULT_STORAGE_QUOTA } from '@/services/constants';
 import { isWebAppPlatform } from '@/services/environment';
 import { supabase } from '@/utils/supabase';
 
@@ -29,6 +29,19 @@ export const getStoragePlanData = (token: string) => {
   };
 };
 
+export const getDailyTranslationPlanData = (token: string) => {
+  const data = jwtDecode<Token>(token) || {};
+  const plan = data['plan'] || 'free';
+  const fixedQuota = parseInt(process.env['NEXT_PUBLIC_TRANSLATION_FIXED_QUOTA'] || '0');
+  const quota =
+    fixedQuota || DEFAULT_DAILY_TRANSLATION_QUOTA[plan] || DEFAULT_DAILY_TRANSLATION_QUOTA['free'];
+
+  return {
+    plan,
+    quota,
+  };
+};
+
 export const getAccessToken = async (): Promise<string | null> => {
   // In browser context there might be two instances of supabase one in the app route
   // and the other in the pages route, and they might have different sessions