[EO2-WAVY#120] ML 서버 시작 Interceptor 개발 및 GET /auth/token에 적용

GET /auth/token에 적용한 이유는 해당 API가 호출되었다면 회원가입 또는 로그인이 이루어졌으므로, 조금 후 분석이 일어날 수 있기 때문이다.
차후 Google Analytics와의 연동으로 접속자 수에 따라 ML 서버를 시작 / 종료하게 만들 계획이다.

src/app.module.ts

@@ -25,7 +25,7 @@ import { JwtMiddleware } from './auth/auth-jwt.middleware';
 import { BookmarksModule } from './bookmarks/bookmarks.module';
 import { AwsModule } from './aws/aws.module';
 import { AwsSdkModule } from 'nest-aws-sdk';
-import { Lambda, S3, SharedIniFileCredentials } from 'aws-sdk';
+import { EC2, Lambda, S3, SharedIniFileCredentials } from 'aws-sdk';
 
 const getEnvFilePath = (node_env: string): string => {
     if (node_env === 'dev') {
@@ -115,7 +115,7 @@ const getEnvFilePath = (node_env: string): string => {
                     timeout: 300000,
                 },
             },
-            services: [S3, Lambda],
+            services: [S3, Lambda, EC2],
         }),
         MembersModule,
         PracticesModule,

src/auth/auth.controller.ts

@@ -1,4 +1,10 @@
-import { Controller, Get, Query, UseGuards } from '@nestjs/common';
+import {
+    Controller,
+    Get,
+    Query,
+    UseGuards,
+    UseInterceptors,
+} from '@nestjs/common';
 import { ConfigService } from '@nestjs/config';
 import {
     ApiBadRequestResponse,
@@ -9,6 +15,7 @@ import {
     ApiQuery,
     ApiTags,
 } from '@nestjs/swagger';
+import { StartMLInstanceInterceptor } from 'src/aws/aws-ml-instance.interceptor';
 import { AuthJwt } from './auth-jwt.decorator';
 import { AccessTokenGuard } from './auth.guard';
 import { AuthService } from './auth.service';
@@ -72,6 +79,7 @@ export class AuthController {
         type: GetJwtOutput,
     })
     @Get('token')
+    @UseInterceptors(StartMLInstanceInterceptor)
     getJwtToken(@Query() getJwtInput: GetJwtInput): Promise<GetJwtOutput> {
         return this.authService.getJwt(getJwtInput);
     }

src/aws/aws-ml-instance.interceptor.ts

@@ -0,0 +1,82 @@
+import {
+    CallHandler,
+    ExecutionContext,
+    Injectable,
+    NestInterceptor,
+} from '@nestjs/common';
+import { ConfigService } from '@nestjs/config';
+import { EC2 } from 'aws-sdk';
+import { InjectAwsService } from 'nest-aws-sdk';
+import { Observable } from 'rxjs';
+
+@Injectable()
+export class StartMLInstanceInterceptor implements NestInterceptor {
+    static instanceId: string;
+
+    constructor(
+        @InjectAwsService(EC2)
+        private readonly ec2Service: EC2,
+        private readonly config: ConfigService,
+    ) {
+        StartMLInstanceInterceptor.instanceId =
+            this.config.get('AWS_ML_INSTANCE_ID');
+    }
+    intercept(
+        context: ExecutionContext,
+        next: CallHandler<any>,
+    ): Observable<any> | Promise<Observable<any>> {
+        this.startInstance();
+        return next.handle();
+    }
+
+    async startInstance() {
+        const instanceStatusResult = await this.ec2Service
+            .describeInstances({
+                DryRun: false,
+                InstanceIds: [StartMLInstanceInterceptor.instanceId],
+            })
+            .promise();
+
+        if (instanceStatusResult.$response.error) {
+            const error = instanceStatusResult.$response.error;
+            const errString = `${error.name}(${error.code}): ${error.message}`;
+            throw Error(errString);
+        }
+
+        const mlInstance = instanceStatusResult.Reservations[0].Instances[0];
+        const instanceState = mlInstance.State.Name;
+
+        if (instanceState == 'stopping') {
+            this.startWhileStopping();
+        } else if (instanceState == 'stopped') {
+            this.start();
+        } else if (
+            instanceState == 'terminated' ||
+            instanceState == 'shutting-down'
+        ) {
+            throw new Error(`!!! MLInstance is ${instanceState}. !!!`);
+        }
+    }
+
+    private async start() {
+        const result = await this.ec2Service
+            .startInstances({
+                DryRun: false,
+                InstanceIds: [StartMLInstanceInterceptor.instanceId],
+            })
+            .promise();
+        return result.StartingInstances[0].InstanceId;
+    }
+    private async startWhileStopping() {
+        await this.ec2Service
+            .waitFor('instanceStopped', {
+                DryRun: false,
+                InstanceIds: [StartMLInstanceInterceptor.instanceId],
+                $waiter: {
+                    delay: 3,
+                },
+            })
+            .promise();
+        return await this.start();
+    }
+}

src/aws/aws.module.ts

@@ -5,11 +5,22 @@ import { TypeOrmModule } from '@nestjs/typeorm';
 import { Analysis } from 'src/analyses/entities/analyses.entity';
 import { UserImageS3Service } from './aws-user-image.service';
 import { UserVideoS3Service } from './aws-user-video.service';
+import { StartMLInstanceInterceptor } from './aws-ml-instance.interceptor';
 
 @Module({
     imports: [TypeOrmModule.forFeature([Analysis])],
-    providers: [AwsService, UserVideoS3Service, UserImageS3Service],
+    providers: [
+        AwsService,
+        UserVideoS3Service,
+        UserImageS3Service,
+        StartMLInstanceInterceptor,
+    ],
     controllers: [AwsController],
-    exports: [AwsService, UserVideoS3Service, UserImageS3Service],
+    exports: [
+        AwsService,
+        UserVideoS3Service,
+        UserImageS3Service,
+        StartMLInstanceInterceptor,
+    ],
 })
 export class AwsModule {}