Reorganize translation interfaces/files

src/app.ts

@@ -120,6 +120,7 @@ import { indexController } from '@/controllers/site.ts';
 import { manifestController } from '@/controllers/manifest.ts';
 import { nodeInfoController, nodeInfoSchemaController } from '@/controllers/well-known/nodeinfo.ts';
 import { nostrController } from '@/controllers/well-known/nostr.ts';
+import { DittoTranslator } from '@/interfaces/DittoTranslator.ts';
 import { auth98Middleware, requireProof, requireRole } from '@/middleware/auth98Middleware.ts';
 import { cspMiddleware } from '@/middleware/cspMiddleware.ts';
 import { metricsMiddleware } from '@/middleware/metricsMiddleware.ts';
@@ -129,7 +130,6 @@ import { requireSigner } from '@/middleware/requireSigner.ts';
 import { signerMiddleware } from '@/middleware/signerMiddleware.ts';
 import { storeMiddleware } from '@/middleware/storeMiddleware.ts';
 import { uploaderMiddleware } from '@/middleware/uploaderMiddleware.ts';
-import { DittoTranslator } from '@/translators/translator.ts';
 import { translatorMiddleware } from '@/middleware/translatorMiddleware.ts';
 
 interface AppEnv extends HonoEnv {

src/caches/translationCache.ts

@@ -0,0 +1,16 @@
+import { LanguageCode } from 'iso-639-1';
+import { LRUCache } from 'lru-cache';
+
+import { MastodonTranslation } from '@/entities/MastodonTranslation.ts';
+import { Time } from '@/utils/time.ts';
+
+/** Entity returned by DittoTranslator and LRUCache */
+interface DittoTranslation {
+  data: MastodonTranslation;
+}
+
+/** Translations LRU cache. */
+export const translationCache = new LRUCache<`${LanguageCode}-${string}`, DittoTranslation>({
+  max: 1000,
+  ttl: Time.hours(6),
+});

src/controllers/api/translate.ts

@@ -2,10 +2,11 @@ import { LanguageCode } from 'iso-639-1';
 import { z } from 'zod';
 
 import { AppController } from '@/app.ts';
-import { localeSchema } from '@/schema.ts';
+import { translationCache } from '@/caches/translationCache.ts';
-import { dittoTranslations, dittoTranslationsKey, MastodonTranslation } from '@/translators/translator.ts';
+import { MastodonTranslation } from '@/entities/MastodonTranslation.ts';
-import { parseBody } from '@/utils/api.ts';
 import { getEvent } from '@/queries.ts';
+import { localeSchema } from '@/schema.ts';
+import { parseBody } from '@/utils/api.ts';
 import { renderStatus } from '@/views/mastodon/statuses.ts';
 
 const translateSchema = z.object({
@@ -45,11 +46,11 @@ const translateController: AppController = async (c) => {
     return c.json({ error: 'Bad request.', schema: result.error }, 400);
   }
 
-  const translatedId = `${lang}-${id}` as dittoTranslationsKey;
+  const cacheKey: `${LanguageCode}-${string}` = `${lang}-${id}`;
-  const translationCache = dittoTranslations.get(translatedId);
+  const cached = translationCache.get(cacheKey);
 
-  if (translationCache) {
+  if (cached) {
-    return c.json(translationCache.data, 200);
+    return c.json(cached.data, 200);
   }
 
   const mediaAttachments = status?.media_attachments.map((value) => {
@@ -68,7 +69,7 @@ const translateController: AppController = async (c) => {
       media_attachments: [],
       poll: null,
       detected_source_language: event.language ?? 'en',
-      provider: translator.getProvider(),
+      provider: translator.provider,
     };
 
     if ((status?.poll as MastodonTranslation['poll'])?.options) {
@@ -130,10 +131,10 @@ const translateController: AppController = async (c) => {
 
     mastodonTranslation.detected_source_language = data.source_lang;
 
-    dittoTranslations.set(translatedId, { data: mastodonTranslation });
+    translationCache.set(cacheKey, { data: mastodonTranslation });
     return c.json(mastodonTranslation, 200);
   } catch (e) {
-    if (e instanceof Error && e.message?.includes('not supported')) {
+    if (e instanceof Error && e.message.includes('not supported')) {
       return c.json({ error: `Translation of source language '${event.language}' not supported` }, 422);
     }
     return c.json({ error: 'Service Unavailable' }, 503);

src/entities/MastodonTranslation.ts

@@ -0,0 +1,17 @@
+import { LanguageCode } from 'iso-639-1';
+
+/** https://docs.joinmastodon.org/entities/Translation/ */
+export interface MastodonTranslation {
+  /** HTML-encoded translated content of the status. */
+  content: string;
+  /** The translated spoiler warning of the status. */
+  spoiler_text: string;
+  /** The translated media descriptions of the status. */
+  media_attachments: { id: string; description: string }[];
+  /** The translated poll of the status. */
+  poll: { id: string; options: { title: string }[] } | null;
+  //** The language of the source text, as auto-detected by the machine translation provider. */
+  detected_source_language: LanguageCode;
+  /** The service that provided the machine translation. */
+  provider: string;
+}

src/interfaces/DittoTranslator.ts

@@ -0,0 +1,18 @@
+import type { LanguageCode } from 'iso-639-1';
+
+/** DittoTranslator class, used for status translation. */
+export interface DittoTranslator {
+  /** Translate the 'content' into 'targetLanguage'. */
+  translate(
+    /** Texts to translate. */
+    texts: string[],
+    /** The language of the source texts. */
+    sourceLanguage: LanguageCode | undefined,
+    /** The texts will be translated into this language. */
+    targetLanguage: LanguageCode,
+    /** Custom options. */
+    opts?: { signal?: AbortSignal },
+  ): Promise<{ results: string[]; source_lang: LanguageCode }>;
+  /** Provider name, eg `DeepL.com` */
+  provider: string;
+}

src/translators/DeepLTranslator.ts

@@ -1,7 +1,7 @@
 import { LanguageCode } from 'iso-639-1';
 import { z } from 'zod';
 
-import { DittoTranslator, SourceLanguage, TargetLanguage } from '@/translators/translator.ts';
+import { DittoTranslator } from '@/interfaces/DittoTranslator.ts';
 import { languageSchema } from '@/schema.ts';
 
 interface DeepLTranslatorOpts {
@@ -28,8 +28,8 @@ export class DeepLTranslator implements DittoTranslator {
 
   async translate(
     texts: string[],
-    source: SourceLanguage | undefined,
+    source: LanguageCode | undefined,
-    dest: TargetLanguage,
+    dest: LanguageCode,
     opts?: { signal?: AbortSignal },
   ) {
     const { translations } = await this.translateMany(texts, source, dest, opts);
@@ -43,8 +43,8 @@ export class DeepLTranslator implements DittoTranslator {
   /** DeepL translate request. */
   private async translateMany(
     texts: string[],
-    source: SourceLanguage | undefined,
+    source: LanguageCode | undefined,
-    targetLanguage: TargetLanguage,
+    targetLanguage: LanguageCode,
     opts?: { signal?: AbortSignal },
   ) {
     const body: any = {

src/translators/LibreTranslateTranslator.ts

@@ -1,7 +1,7 @@
 import { LanguageCode } from 'iso-639-1';
 import { z } from 'zod';
 
-import { DittoTranslator, SourceLanguage, TargetLanguage } from '@/translators/translator.ts';
+import { DittoTranslator } from '@/interfaces/DittoTranslator.ts';
 import { languageSchema } from '@/schema.ts';
 
 interface LibreTranslateTranslatorOpts {
@@ -28,8 +28,8 @@ export class LibreTranslateTranslator implements DittoTranslator {
 
   async translate(
     texts: string[],
-    source: SourceLanguage | undefined,
+    source: LanguageCode | undefined,
-    dest: TargetLanguage,
+    dest: LanguageCode,
     opts?: { signal?: AbortSignal },
   ) {
     const translations = await Promise.all(

src/translators/translator.ts

@@ -1,57 +0,0 @@
-import { LanguageCode } from 'iso-639-1';
-import { LRUCache } from 'lru-cache';
-
-import { Time } from '@/utils/time.ts';
-
-/** Original language of the post */
-export type SourceLanguage = LanguageCode;
-
-/** Content will be translated to this language */
-export type TargetLanguage = LanguageCode;
-
-/** Entity returned by DittoTranslator and LRUCache */
-type DittoTranslation = {
-  data: MastodonTranslation;
-};
-
-export type MastodonTranslation = {
-  /** HTML-encoded translated content of the status. */
-  content: string;
-  /** The translated spoiler warning of the status. */
-  spoiler_text: string;
-  /** The translated media descriptions of the status. */
-  media_attachments: { id: string; description: string }[];
-  /** The translated poll of the status. */
-  poll: { id: string; options: { title: string }[] } | null;
-  //** The language of the source text, as auto-detected by the machine translation provider. */
-  detected_source_language: SourceLanguage;
-  /** The service that provided the machine translation. */
-  provider: string;
-};
-
-/** DittoTranslator class, used for status translation. */
-export interface DittoTranslator {
-  /** Translate the 'content' into 'targetLanguage'. */
-  translate(
-    texts: string[],
-    /** The language of the source text/status. */
-    sourceLanguage: SourceLanguage | undefined,
-    /** The status content will be translated into this language. */
-    targetLanguage: TargetLanguage,
-    /** Custom options. */
-    opts?: { signal?: AbortSignal },
-  ): Promise<{ results: string[]; source_lang: SourceLanguage }>;
-  /** Provider name, eg `DeepL.com` */
-  provider: string;
-}
-
-/** Includes the TARGET language and the status id.
- *  Example: en-390f5b01b49a8ee6e13fe917420c023d889b3da8e983a14c9e84587e43d12c15
- *  The example above means:
- *  I want the status 390f5b01b49a8ee6e13fe917420c023d889b3da8e983a14c9e84587e43d12c15 translated to english (if it exists in the LRUCache). */
-export type dittoTranslationsKey = `${TargetLanguage}-${string}`;
-
-export const dittoTranslations = new LRUCache<dittoTranslationsKey, DittoTranslation>({
-  max: 1000,
-  ttl: Time.hours(6),
-});