[FEATURE] 영어공지 자동 번역 기능

Fixes #89

.vscode/settings.json

@@ -2,7 +2,9 @@
   "cSpell.words": [
     "axios",
     "datasources",
+    "datetime",
     "dbml",
+    "deepl",
     "gistory",
     "gsainfoteam",
     "infoteam",

package.json

@@ -36,6 +36,7 @@
     "class-validator": "^0.14.1",
     "cookie-parser": "^1.4.6",
     "dayjs": "^1.11.10",
+    "deepl-node": "^1.14.0",
     "express-basic-auth": "^1.2.1",
     "firebase-admin": "^12.1.0",
     "html-to-text": "^9.0.5",

src/ai/ai.controller.ts

@@ -38,9 +38,6 @@ export class AiController {
   async translate(
     @Body() translateDto: TranslateDto,
   ): Promise<TranslateResDto> {
-    return {
-      text: translateDto.text,
-      lang: translateDto.targetLang,
-    };
+    return this.aiService.translate(translateDto);
   }
 }

src/ai/ai.service.ts

@@ -1,19 +1,34 @@
-import { Injectable } from '@nestjs/common';
+import {
+  Injectable,
+  InternalServerErrorException,
+  Logger,
+} from '@nestjs/common';
 import { ConfigService } from '@nestjs/config';
 import { DeadlineResponse } from './types/deadlineResponse.type';
-import OpenAI from 'openai';
+import OpenAI, { InternalServerError } from 'openai';
 import {
   ChatCompletionMessageParam,
   ChatCompletionSystemMessageParam,
   ChatCompletionUserMessageParam,
 } from 'openai/resources';
+import * as deepl from 'deepl-node';
+import { TranslateResDto } from './dto/res/translateRes.dto';
+import { TranslateDto } from './dto/req/translate.dto';
+
 @Injectable()
 export class AiService {
+  private readonly logger = new Logger(AiService.name, {
+    timestamp: true,
+  });
   private readonly openai: OpenAI;
+  private readonly translator: deepl.Translator;
   constructor(private readonly configService: ConfigService) {
     this.openai = new OpenAI({
-      apiKey: this.configService.get<string>('OPENAI_API_KEY'),
+      apiKey: this.configService.getOrThrow<string>('OPENAI_API_KEY'),
     });
+    this.translator = new deepl.Translator(
+      this.configService.getOrThrow<string>('DEEPL_API_KEY'),
+    );
   }
 
   async detectDeadline(body: string, createdAt: Date): Promise<Date | null> {
@@ -64,4 +79,22 @@ export class AiService {
       return null;
     }
   }
+
+  async translate({
+    text,
+    targetLang,
+  }: TranslateDto): Promise<TranslateResDto> {
+    this.logger.log(`translate called`);
+    const result = await this.translator
+      .translateText(text, null, targetLang)
+      .catch((error) => {
+        this.logger.error(`deepl translation error: ${error.message}`);
+        throw new InternalServerErrorException(error.message);
+      });
+    this.logger.log(`translate finished`);
+    return {
+      text: result.text,
+      lang: targetLang,
+    };
+  }
 }

src/ai/dto/req/translate.dto.ts

@@ -1,5 +1,7 @@
 import { ApiProperty } from '@nestjs/swagger';
+import { Transform } from 'class-transformer';
 import { IsLocale, IsString } from 'class-validator';
+import * as deepl from 'deepl-node';
 
 export class TranslateDto {
   @ApiProperty({
@@ -14,5 +16,11 @@ export class TranslateDto {
     example: 'ko',
   })
   @IsLocale()
-  targetLang: string;
+  @Transform(({ value }) => {
+    if (value === 'en') {
+      return 'en-US';
+    }
+    return value;
+  })
+  targetLang: deepl.TargetLanguageCode;
 }

src/ai/dto/res/translateRes.dto.ts

@@ -1,4 +1,5 @@
 import { ApiProperty } from '@nestjs/swagger';
+import * as deepl from 'deepl-node';
 
 export class TranslateResDto {
   @ApiProperty({
@@ -11,5 +12,5 @@ export class TranslateResDto {
     description: 'Language of the translated text',
     example: 'en',
   })
-  lang: string;
+  lang: deepl.TargetLanguageCode;
 }