enhance: add LLM translation support with openai compatible API

CHANGELOG.md

@@ -52,6 +52,7 @@
 - Fix: ActivityPubリクエストURLチェック実装は仕様に従っていないのを修正
 - Fix: 連合無しモードでも外部から照会可能だった問題を修正
 - Fix: テスト用WebHookのペイロードの`emojis`パラメータが実際のものと異なる問題を修正
+- Enhance: add LLM translation support with OpenAI compatible API
 
 ## 2025.3.1
 

packages/backend/migration/1740989976502-addLlmTranslatorSupport.js

@@ -0,0 +1,36 @@
+/*
+ * SPDX-FileCopyrightText: syuilo and misskey-project
+ * SPDX-License-Identifier: AGPL-3.0-only
+ */
+
+export class  AddLlmTranslatorSupport1740989976502 {
+    name = 'AddLlmTranslatorSupport1740989976502'
+
+    async up(queryRunner) {
+        await queryRunner.query(`ALTER TABLE "meta" ADD "enableLlmTranslator" boolean NOT NULL DEFAULT false`);
+        await queryRunner.query(`ALTER TABLE "meta" ADD "enableLlmTranslatorRedisCache" boolean NOT NULL DEFAULT false`);
+        await queryRunner.query(`ALTER TABLE "meta" ADD "llmTranslatorRedisCacheTtl" integer NOT NULL DEFAULT '2880'`);
+        await queryRunner.query(`ALTER TABLE "meta" ADD "llmTranslatorBaseUrl" character varying(1024)`);
+        await queryRunner.query(`ALTER TABLE "meta" ADD "llmTranslatorApiKey" character varying(1024)`);
+        await queryRunner.query(`ALTER TABLE "meta" ADD "llmTranslatorModel" character varying(1024)`);
+        await queryRunner.query(`ALTER TABLE "meta" ADD "llmTranslatorTemperature" real`);
+        await queryRunner.query(`ALTER TABLE "meta" ADD "llmTranslatorTopP" real`);
+        await queryRunner.query(`ALTER TABLE "meta" ADD "llmTranslatorMaxTokens" integer`);
+        await queryRunner.query(`ALTER TABLE "meta" ADD "llmTranslatorSysPrompt" character varying(1024)`);
+        await queryRunner.query(`ALTER TABLE "meta" ADD "llmTranslatorUserPrompt" character varying(1024)`);
+    }
+
+    async down(queryRunner) {
+        await queryRunner.query(`ALTER TABLE "meta" DROP COLUMN "enableLlmTranslator"`);
+        await queryRunner.query(`ALTER TABLE "meta" DROP COLUMN "enableLlmTranslatorRedisCache"`);
+        await queryRunner.query(`ALTER TABLE "meta" DROP COLUMN "llmTranslatorRedisCacheTtl"`);
+        await queryRunner.query(`ALTER TABLE "meta" DROP COLUMN "llmTranslatorBaseUrl"`);
+        await queryRunner.query(`ALTER TABLE "meta" DROP COLUMN "llmTranslatorApiKey"`);
+        await queryRunner.query(`ALTER TABLE "meta" DROP COLUMN "llmTranslatorModel"`);
+        await queryRunner.query(`ALTER TABLE "meta" DROP COLUMN "llmTranslatorTemperature"`);
+        await queryRunner.query(`ALTER TABLE "meta" DROP COLUMN "llmTranslatorTopP"`);
+        await queryRunner.query(`ALTER TABLE "meta" DROP COLUMN "llmTranslatorMaxTokens"`);
+        await queryRunner.query(`ALTER TABLE "meta" DROP COLUMN "llmTranslatorSysPrompt"`);
+        await queryRunner.query(`ALTER TABLE "meta" DROP COLUMN "llmTranslatorUserPrompt"`);
+    }
+}

packages/backend/package.json

@@ -147,6 +147,7 @@
 		"oauth": "0.10.2",
 		"oauth2orize": "1.12.0",
 		"oauth2orize-pkce": "0.1.2",
+		"openai": "4.86.1",
 		"os-utils": "0.0.14",
 		"otpauth": "9.3.6",
 		"parse5": "7.2.1",

packages/backend/src/core/entities/MetaEntityService.ts

@@ -121,7 +121,7 @@ export class MetaEntityService {
 			enableEmail: instance.enableEmail,
 			enableServiceWorker: instance.enableServiceWorker,
 
-			translatorAvailable: instance.deeplAuthKey != null,
+			translatorAvailable: instance.deeplAuthKey != null || instance.enableLlmTranslator,
 
 			serverRules: instance.serverRules,
 

packages/backend/src/models/Meta.ts

@@ -664,4 +664,64 @@ export class MiMeta {
 		nullable: true,
 	})
 	public googleAnalyticsMeasurementId: string | null;
+
+	@Column('boolean', {
+		default: false,
+	})
+	public enableLlmTranslator: boolean;
+
+	@Column('boolean', {
+		default: false,
+	})
+	public enableLlmTranslatorRedisCache: boolean;
+
+	@Column('integer', {
+		default: 2880,
+	})
+	public llmTranslatorRedisCacheTtl: number;
+
+	@Column('varchar', {
+		length: 1024,
+		nullable: true,
+	})
+	public llmTranslatorBaseUrl: string | null;
+
+	@Column('varchar', {
+		length: 1024,
+		nullable: true,
+	})
+	public llmTranslatorApiKey: string | null;
+
+	@Column('varchar', {
+		length: 1024,
+		nullable: true,
+	})
+	public llmTranslatorModel: string | null;
+
+	@Column('real', {
+		nullable: true,
+	})
+	public llmTranslatorTemperature: number | null;
+
+	@Column('real', {
+		nullable: true,
+	})
+	public llmTranslatorTopP: number | null;
+
+	@Column('integer', {
+		nullable: true,
+	})
+	public llmTranslatorMaxTokens: number | null;
+
+	@Column('varchar', {
+		length: 1024,
+		nullable: true,
+	})
+	public llmTranslatorSysPrompt: string | null;
+
+	@Column('varchar', {
+		length: 1024,
+		nullable: true,
+	})
+	public llmTranslatorUserPrompt: string | null;
 }

packages/backend/src/server/api/endpoints/admin/meta.ts

@@ -528,6 +528,50 @@ export const meta = {
 					optional: false, nullable: false,
 				},
 			},
+			enableLlmTranslator: {
+				type: 'boolean',
+				optional: false, nullable: false,
+			},
+			enableLlmTranslatorRedisCache: {
+				type: 'boolean',
+				optional: false, nullable: false,
+			},
+			llmTranslatorRedisCacheTtl: {
+				type: 'number',
+				optional: false, nullable: false,
+			},
+			llmTranslatorBaseUrl: {
+				type: 'string',
+				optional: false, nullable: true,
+			},
+			llmTranslatorApiKey: {
+				type: 'string',
+				optional: false, nullable: true,
+			},
+			llmTranslatorModel: {
+				type: 'string',
+				optional: false, nullable: true,
+			},
+			llmTranslatorTemperature: {
+				type: 'number',
+				optional: false, nullable: true,
+			},
+			llmTranslatorTopP: {
+				type: 'number',
+				optional: false, nullable: true,
+			},
+			llmTranslatorMaxTokens: {
+				type: 'number',
+				optional: false, nullable: true,
+			},
+			llmTranslatorSysPrompt: {
+				type: 'string',
+				optional: false, nullable: true,
+			},
+			llmTranslatorUserPrompt: {
+				type: 'string',
+				optional: false, nullable: true,
+			},
 		},
 	},
 } as const;
@@ -597,7 +641,7 @@ export default class extends Endpoint<typeof meta, typeof paramDef> { // eslint-
 				defaultDarkTheme: instance.defaultDarkTheme,
 				enableEmail: instance.enableEmail,
 				enableServiceWorker: instance.enableServiceWorker,
-				translatorAvailable: instance.deeplAuthKey != null,
+				translatorAvailable: instance.deeplAuthKey != null || instance.enableLlmTranslator,
 				cacheRemoteFiles: instance.cacheRemoteFiles,
 				cacheRemoteSensitiveFiles: instance.cacheRemoteSensitiveFiles,
 				pinnedUsers: instance.pinnedUsers,
@@ -672,6 +716,17 @@ export default class extends Endpoint<typeof meta, typeof paramDef> { // eslint-
 				urlPreviewSummaryProxyUrl: instance.urlPreviewSummaryProxyUrl,
 				federation: instance.federation,
 				federationHosts: instance.federationHosts,
+				enableLlmTranslator: instance.enableLlmTranslator,
+				enableLlmTranslatorRedisCache: instance.enableLlmTranslatorRedisCache,
+				llmTranslatorRedisCacheTtl: instance.llmTranslatorRedisCacheTtl,
+				llmTranslatorBaseUrl: instance.llmTranslatorBaseUrl,
+				llmTranslatorApiKey: instance.llmTranslatorApiKey,
+				llmTranslatorModel: instance.llmTranslatorModel,
+				llmTranslatorMaxTokens: instance.llmTranslatorMaxTokens,
+				llmTranslatorTemperature: instance.llmTranslatorTemperature,
+				llmTranslatorTopP: instance.llmTranslatorTopP,
+				llmTranslatorSysPrompt: instance.llmTranslatorSysPrompt,
+				llmTranslatorUserPrompt: instance.llmTranslatorUserPrompt,
 			};
 		});
 	}

packages/backend/src/server/api/endpoints/admin/update-meta.ts

@@ -185,6 +185,17 @@ export const paramDef = {
 				type: 'string',
 			},
 		},
+		enableLlmTranslator: { type: 'boolean' },
+		enableLlmTranslatorRedisCache: { type: 'boolean' },
+		llmTranslatorRedisCacheTtl: { type: 'integer' },
+		llmTranslatorBaseUrl: { type: 'string', nullable: true },
+		llmTranslatorApiKey: { type: 'string', nullable: true },
+		llmTranslatorModel: { type: 'string', nullable: true },
+		llmTranslatorTemperature: { type: 'number', nullable: true },
+		llmTranslatorTopP: { type: 'number', nullable: true },
+		llmTranslatorMaxTokens: { type: 'integer', nullable: true },
+		llmTranslatorSysPrompt: { type: 'string', nullable: true },
+		llmTranslatorUserPrompt: { type: 'string', nullable: true },
 	},
 	required: [],
 } as const;
@@ -675,6 +686,70 @@ export default class extends Endpoint<typeof meta, typeof paramDef> { // eslint-
 				set.federationHosts = ps.federationHosts.filter(Boolean).map(x => x.toLowerCase());
 			}
 
+			if (ps.enableLlmTranslator !== undefined) {
+				set.enableLlmTranslator = ps.enableLlmTranslator;
+			}
+
+			if (ps.enableLlmTranslatorRedisCache !== undefined) {
+				set.enableLlmTranslatorRedisCache = ps.enableLlmTranslatorRedisCache;
+			}
+
+			if (ps.llmTranslatorRedisCacheTtl !== undefined) {
+				set.llmTranslatorRedisCacheTtl = ps.llmTranslatorRedisCacheTtl;
+			}
+
+			if (ps.llmTranslatorBaseUrl !== undefined) {
+				if (ps.llmTranslatorBaseUrl === '') {
+					set.llmTranslatorBaseUrl = null;
+				} else {
+					set.llmTranslatorBaseUrl = ps.llmTranslatorBaseUrl;
+				}
+			}
+
+			if (ps.llmTranslatorApiKey !== undefined) {
+				if (ps.llmTranslatorApiKey === '') {
+					set.llmTranslatorApiKey = null;
+				} else {
+					set.llmTranslatorApiKey = ps.llmTranslatorApiKey;
+				}
+			}
+
+			if (ps.llmTranslatorModel !== undefined) {
+				if (ps.llmTranslatorModel === '') {
+					set.llmTranslatorModel = null;
+				} else {
+					set.llmTranslatorModel = ps.llmTranslatorModel;
+				}
+			}
+
+			if (ps.llmTranslatorTemperature !== undefined) {
+				set.llmTranslatorTemperature = ps.llmTranslatorTemperature;
+			}
+
+			if (ps.llmTranslatorTopP !== undefined) {
+				set.llmTranslatorTopP = ps.llmTranslatorTopP;
+			}
+
+			if (ps.llmTranslatorMaxTokens !== undefined) {
+				set.llmTranslatorMaxTokens = ps.llmTranslatorMaxTokens;
+			}
+
+			if (ps.llmTranslatorSysPrompt !== undefined) {
+				if (ps.llmTranslatorSysPrompt === '') {
+					set.llmTranslatorSysPrompt = null;
+				} else {
+					set.llmTranslatorSysPrompt = ps.llmTranslatorSysPrompt;
+				}
+			}
+
+			if (ps.llmTranslatorUserPrompt !== undefined) {
+				if (ps.llmTranslatorUserPrompt === '') {
+					set.llmTranslatorUserPrompt = null;
+				} else {
+					set.llmTranslatorUserPrompt = ps.llmTranslatorUserPrompt;
+				}
+			}
+
 			const before = await this.metaService.fetch(true);
 
 			await this.metaService.update(set);

packages/backend/src/server/api/endpoints/notes/translate.ts

@@ -5,14 +5,16 @@
 
 import { URLSearchParams } from 'node:url';
 import { Inject, Injectable } from '@nestjs/common';
+import { OpenAI } from 'openai';
+import * as Redis from 'ioredis';
 import { Endpoint } from '@/server/api/endpoint-base.js';
 import { NoteEntityService } from '@/core/entities/NoteEntityService.js';
 import { HttpRequestService } from '@/core/HttpRequestService.js';
 import { GetterService } from '@/server/api/GetterService.js';
 import { RoleService } from '@/core/RoleService.js';
-import { ApiError } from '../../error.js';
 import { MiMeta } from '@/models/_.js';
 import { DI } from '@/di-symbols.js';
+import { ApiError } from '../../error.js';
 
 export const meta = {
 	tags: ['notes'],
@@ -63,6 +65,9 @@ export default class extends Endpoint<typeof meta, typeof paramDef> { // eslint-
 		@Inject(DI.meta)
 		private serverSettings: MiMeta,
 
+		@Inject(DI.redis)
+		private redisClient: Redis.Redis,
+
 		private noteEntityService: NoteEntityService,
 		private getterService: GetterService,
 		private httpRequestService: HttpRequestService,
@@ -87,6 +92,13 @@ export default class extends Endpoint<typeof meta, typeof paramDef> { // eslint-
 				return;
 			}
 
+			if (this.serverSettings.enableLlmTranslator) {
+				const res = await this.llmTranslate(note.text, ps.targetLang, note.id);
+				return {
+					text: res,
+				};
+			}
+
 			if (this.serverSettings.deeplAuthKey == null) {
 				throw new ApiError(meta.errors.unavailable);
 			}
@@ -123,4 +135,44 @@ export default class extends Endpoint<typeof meta, typeof paramDef> { // eslint-
 			};
 		});
 	}
+
+	private async llmTranslate(text: string, targetLang: string, noteId: string): Promise<string> {
+		if (this.serverSettings.enableLlmTranslatorRedisCache) {
+			const key = `llmTranslate:${targetLang}:${noteId}`;
+			const cached = await this.redisClient.get(key);
+			if (cached != null) {
+				this.redisClient.expire(key, this.serverSettings.llmTranslatorRedisCacheTtl * 60);
+				return cached;
+			}
+			const res = await this.getLlmRes(text, targetLang);
+			await this.redisClient.set(key, res);
+			this.redisClient.expire(key, this.serverSettings.llmTranslatorRedisCacheTtl * 60);
+			return res;
+		} else {
+			return this.getLlmRes(text, targetLang);
+		}
+	}
+
+	private async getLlmRes(text: string, targetLang: string): Promise<string> {
+		const client = new OpenAI({
+			baseURL: this.serverSettings.llmTranslatorBaseUrl,
+			apiKey: this.serverSettings.llmTranslatorApiKey ?? '',
+		});
+		const message = [];
+		if (this.serverSettings.llmTranslatorSysPrompt) {
+			message.push({ role: 'system' as const, content: this.serverSettings.llmTranslatorSysPrompt.replace('{targetLang}', targetLang).replace('{text}', text) });
+		}
+		if (this.serverSettings.llmTranslatorUserPrompt) {
+			message.push({ role: 'user' as const, content: this.serverSettings.llmTranslatorUserPrompt.replace('{targetLang}', targetLang).replace('{text}', text) });
+		}
+		const completion = await client.chat.completions.create({
+			messages: message,
+			model: this.serverSettings.llmTranslatorModel ?? '',
+			temperature: this.serverSettings.llmTranslatorTemperature,
+			max_tokens: this.serverSettings.llmTranslatorMaxTokens,
+			top_p: this.serverSettings.llmTranslatorTopP,
+		});
+
+		return completion.choices[0].message.content ?? '';
+	}
 }

packages/frontend/src/components/MkNote.vue

@@ -81,7 +81,7 @@ SPDX-License-Identifier: AGPL-3.0-only
 						<div v-if="translating || translation" :class="$style.translation">
 							<MkLoading v-if="translating" mini/>
 							<div v-else-if="translation">
-								<b>{{ i18n.tsx.translatedFrom({ x: translation.sourceLang }) }}: </b>
+								<b v-if="translation.sourceLang">{{ i18n.tsx.translatedFrom({ x: translation.sourceLang }) }}: </b>
 								<Mfm :text="translation.text" :author="appearNote.user" :nyaize="'respect'" :emojiUrls="appearNote.emojis" class="_selectable"/>
 							</div>
 						</div>

packages/frontend/src/components/MkNoteDetailed.vue

@@ -103,7 +103,7 @@ SPDX-License-Identifier: AGPL-3.0-only
 				<div v-if="translating || translation" :class="$style.translation">
 					<MkLoading v-if="translating" mini/>
 					<div v-else-if="translation">
-						<b>{{ i18n.tsx.translatedFrom({ x: translation.sourceLang }) }}: </b>
+						<b v-if="translation.sourceLang">{{ i18n.tsx.translatedFrom({ x: translation.sourceLang }) }}: </b>
 						<Mfm :text="translation.text" :author="appearNote.user" :nyaize="'respect'" :emojiUrls="appearNote.emojis" class="_selectable"/>
 					</div>
 				</div>