Interceptors

.env.example

@@ -8,13 +8,18 @@ DATABASE_PASSWORD=postgres
 WRITE_DATABASE_NAME=master-db
 READ_DATABASE_NAME=slave-db
 
+WRITE_CONNECTION_NAME=
+READ_CONNECTION_NAME=
+
 TYPEORM_ENTITIES=/**/core/entities/**.entity{.ts,.js}
 TYPEORM_MIGRATIONS=/database/migrations/*{.ts,.js}
 TYPEORM_MIGRATIONS_DIR=src/database/migrations
 TYPEORM_LOGGING=true
 TYPEORM_SYNCHRONIZE=false
 TYPEORM_MIGRATION_RUN=false
 
+JWT_SECRET_KEY=jwt-secret-key
+
 DROPBOX_TOKEN=
 DROPBOX_KEY=
 DROPBOX_SECRET=

.gitignore

@@ -22,5 +22,6 @@ dist/*
 
 .env
 .env.development
+.env.docker
 
 app.yaml

README.md

@@ -1,3 +1,45 @@
+# System Design
+
+## FUNCTION REQUIREMENTS:
+
+    - user can login/logout
+    - user can post the article
+    - user can upload file
+    - user can searching
+    - user can like, comment, follow
+
+## NON FUNCTION REQUIREMENTS:
+
+    - high availability, latency < 500ms
+    - total users: 100M
+    - daily active user: 1M
+    - 1 user upload 2 image per day
+    - image size < 5MB
+    --> Write 1 * 2 * 5MB * 1M = 10MB = 10TB
+    - QPS: Write: 1M * 2(image upload) / (24hours * 60 minutes * 60 seconds) == 25 QPS
+    - QPS: Read: 1M * 50 / (24hours * 60 minutes * 60 seconds) == 580 QPS
+    ==> READ HEAVY
+    - No lost for image
+
+## API Design
+
+    Login: - request: { username, password} - response: { accessToken, refreshToken }
+    Logout - request: { token } - response: boolean
+    Post Article - request: { userId, title, description, content, hastag } - response: articleId
+    Upload File - request: { string base 64 } - response: file_url
+    Searching - request: { keyword } - response: [ article ]
+    Like - request: { userId, articleId } - response: boolean
+    Comment - request: { userId, articleId, content } - response: commentId | Comment
+    Follow - request: { currentUserId, toUserId } - response: boolean
+
+## DB Schema
+
+![alt text](./assets/db-schema.png)
+
+## Design system
+
+![alt text](./assets/architect.png)
+
 # Getting started
 
 ## Installation
@@ -25,6 +67,7 @@ Run migration
 ---
 
 ## Running on docker
+
 Build images
 
     docker-compose build

docker-compose.yaml

@@ -14,10 +14,10 @@ services:
       - rabbitmq
       - redis
     env_file:
-      - .env
-    environment:
-      - NODE_ENV=staging
-      - DATABASE_HOST=host.docker.internal
+      - .env.docker
+    networks:
+      - social-network
+
   social-api-2:
     build:
       context: .
@@ -31,10 +31,9 @@ services:
       - rabbitmq
       - redis
     env_file:
-      - .env
-    environment:
-      - NODE_ENV=staging
-      - DATABASE_HOST=host.docker.internal
+      - .env.docker
+    networks:
+      - social-network
 
   db:
     container_name: social-postgres
@@ -46,17 +45,26 @@ services:
       - /data/postgres/
     ports:
       - 5432:5432
+    networks:
+      - social-network
+
   rabbitmq:
     container_name: social-rabbitmq
     image: rabbitmq:3-management
     ports:
       - "15672:15672"
       - "5672:5672"
+    networks:
+      - social-network
+
   redis:
     container_name: social-redis
     image: "redis:alpine"
     ports:
       - "6379:6379"
+    networks:
+      - social-network
+
   nginx:
     container_name: social-nginx
     build: ./nginx
@@ -65,3 +73,9 @@ services:
     depends_on:
       - social-api-1
       - social-api-2
+    networks:
+      - social-network
+
+networks:
+  social-network:
+    driver: bridge

package.json

@@ -29,11 +29,13 @@
     "@nestjs/config": "^2.2.0",
     "@nestjs/core": "^7.0.5",
     "@nestjs/cqrs": "^9.0.1",
+    "@nestjs/microservices": "7.2",
     "@nestjs/platform-express": "^7.0.5",
     "@nestjs/swagger": "^4.4.0",
     "@nestjs/testing": "^7.0.5",
     "@nestjs/typeorm": "^7.0.0",
     "@nestjs/websockets": "^7.0.5",
+    "amqp-connection-manager": "^4.1.14",
     "amqplib": "^0.10.3",
     "argon2": "^0.26.2",
     "aws-sdk": "^2.1301.0",

src/app.module.ts

@@ -1,60 +1,24 @@
 import { Module } from "@nestjs/common";
 import { ConfigModule } from "@nestjs/config";
-import { TypeOrmModule } from "@nestjs/typeorm";
-import * as dotenv from "dotenv";
-import { AppController } from "./app.controller";
+
 import { ArticleModule } from "./article/article.module";
-import { READ_CONNECTION, WRITE_CONNECTION } from "./config";
+import { DatabaseModule } from "./database/database.module";
 import { MediaModule } from "./media/media.module";
 import { ProfileModule } from "./profile/profile.module";
 import { TagModule } from "./tag/tag.module";
 import { UserModule } from "./user/user.module";
 
-dotenv.config();
-
-const defaultOptions = {
-  type: process.env.DATABASE_ENGINE,
-  host: process.env.DATABASE_HOST,
-  port: parseInt(process.env.DATABASE_PORT),
-  username: process.env.DATABASE_USERNAME,
-  password: process.env.DATABASE_PASSWORD,
-  entities: [__dirname + process.env.TYPEORM_ENTITIES],
-  migrations: [__dirname + process.env.TYPEORM_MIGRATIONS],
-  logging: process.env.TYPEORM_LOGGING === "true",
-  synchronize: process.env.TYPEORM_SYNCHRONIZE === "true",
-  migrationsRun: process.env.TYPEORM_MIGRATION_RUN === "true",
-  migrationsTableName: "migrations",
-  cli: {
-    migrationsDir: process.env.TYPEORM_MIGRATIONS_DIR,
-  },
-};
-
 @Module({
   imports: [
     ConfigModule.forRoot({ isGlobal: true }),
-    TypeOrmModule.forRootAsync({
-      name: WRITE_CONNECTION,
-      useFactory: () => ({
-        ...defaultOptions,
-        type: "postgres",
-        database: process.env.WRITE_DATABASE_NAME,
-      }),
-    }),
-    TypeOrmModule.forRootAsync({
-      name: READ_CONNECTION,
-      useFactory: () => ({
-        ...defaultOptions,
-        type: "postgres",
-        database: process.env.READ_DATABASE_NAME,
-      }),
-    }),
+    DatabaseModule,
     ArticleModule,
     UserModule,
     ProfileModule,
     TagModule,
     MediaModule,
   ],
-  controllers: [AppController],
+  controllers: [],
   providers: [],
 })
 export class ApplicationModule {}

src/article/commands/command.module.ts → src/article/application/commands/command.module.ts

@@ -1,14 +1,15 @@
 import { Module } from "@nestjs/common";
 import { CqrsModule } from "@nestjs/cqrs";
 import { TypeOrmModule } from "@nestjs/typeorm";
-import { CommandHandlers } from ".";
-import { WRITE_CONNECTION } from "../../config";
-import { FollowsEntity } from "../../profile/core/entities/follows.entity";
-import { RabbitMqModule } from "../../rabbitmq/rabbitmq.module";
-import { UserEntity } from "../../user/core";
-import { UserModule } from "../../user/user.module";
-import { ArticleEntity, BlockEntity } from "../core";
-import { CommentEntity } from "../core/entities/comment.entity";
+
+import { CommandHandlers } from "./index";
+import { WRITE_CONNECTION } from "../../../configs";
+import { FollowsEntity } from "../../../profile/core/entities/follows.entity";
+import { RabbitMqModule } from "../../../rabbitmq/rabbitmq.module";
+import { UserEntity } from "../../../user/core";
+import { UserModule } from "../../../user/user.module";
+import { ArticleEntity, BlockEntity } from "../../core";
+import { CommentEntity } from "../../core/entities/comment.entity";
 import { ArticleService } from "../services/article.service";
 
 @Module({

src/article/commands/handlers/create-article.handler.ts → src/article/application/commands/handlers/create-article.handler.ts

@@ -1,13 +1,16 @@
-import { HttpException, HttpStatus } from "@nestjs/common";
+import { HttpException, HttpStatus, Inject } from "@nestjs/common";
 import { CommandHandler, ICommandHandler } from "@nestjs/cqrs";
+import { ClientProxy } from "@nestjs/microservices";
 import { InjectRepository } from "@nestjs/typeorm";
 import { Repository } from "typeorm";
-import { WRITE_CONNECTION } from "../../../config";
-import { PublisherService } from "../../../rabbitmq/publisher.service";
-import { ARTICLE_QUEUE } from "../../../rabbitmq/rabbitmq.constants";
-import { ArticleEntity } from "../../core/entities/article.entity";
-import { MessageType } from "../../core/enums/article.enum";
-import { ArticleRO } from "../../core/interfaces/article.interface";
+
+import { ARTICLE_RMQ_CLIENT, WRITE_CONNECTION } from "../../../../configs";
+import { ArticleEntity } from "../../../core/entities/article.entity";
+import { MessageCmd } from "../../../core/enums/article.enum";
+import {
+  ArticleRO,
+  IPayloadArticleCreated,
+} from "../../../core/interfaces/article.interface";
 import { ArticleService } from "../../services/article.service";
 import { CreateArticleCommand } from "../impl";
 
@@ -18,10 +21,13 @@ export class CreateArticleCommandHandler
   constructor(
     @InjectRepository(ArticleEntity, WRITE_CONNECTION)
     private readonly articleRepository: Repository<ArticleEntity>,
+    @Inject(ARTICLE_RMQ_CLIENT)
+    private readonly articleRmqClient: ClientProxy,
 
-    private readonly articleService: ArticleService,
-    private readonly publisher: PublisherService
-  ) {}
+    private readonly articleService: ArticleService
+  ) {
+    this.articleRmqClient.connect();
+  }
 
   async execute({
     userId,
@@ -39,10 +45,10 @@ export class CreateArticleCommandHandler
       );
 
       if (article) {
-        this.publisher.publish(ARTICLE_QUEUE, {
-          type: MessageType.ARTICLE_CREATED,
-          payload: { article },
-        });
+        this.articleRmqClient.emit<any, IPayloadArticleCreated>(
+          { cmd: MessageCmd.ARTICLE_CREATED },
+          { article }
+        );
       }
 
       return {

src/article/commands/handlers/create-comment.handler.ts → src/article/application/commands/handlers/create-comment.handler.ts

@@ -1,15 +1,14 @@
-import { HttpException, HttpStatus } from "@nestjs/common";
+import { HttpException, HttpStatus, Inject } from "@nestjs/common";
 import { CommandHandler, ICommandHandler } from "@nestjs/cqrs";
+import { ClientProxy } from "@nestjs/microservices";
 import { InjectRepository } from "@nestjs/typeorm";
 import { Repository } from "typeorm";
-import { WRITE_CONNECTION } from "../../../config";
-import { PublisherService } from "../../../rabbitmq/publisher.service";
-import { ARTICLE_QUEUE } from "../../../rabbitmq/rabbitmq.constants";
-import { UserEntity } from "../../../user/core/entities/user.entity";
-import { ArticleEntity } from "../../core/entities/article.entity";
-import { CommentEntity } from "../../core/entities/comment.entity";
-import { MessageType } from "../../core/enums/article.enum";
-import { CommentRO } from "../../core/interfaces/article.interface";
+
+import { ARTICLE_RMQ_CLIENT, WRITE_CONNECTION } from "../../../../configs";
+import { UserEntity } from "../../../../user/core/entities";
+import { ArticleEntity, CommentEntity } from "../../../core/entities";
+import { MessageCmd } from "../../../core/enums";
+import { CommentRO, IPayloadCommentCreated } from "../../../core/interfaces";
 import { ArticleService } from "../../services/article.service";
 import { CreateCommentCommand } from "../impl";
 
@@ -24,10 +23,13 @@ export class CreateCommentCommandHandler
     private readonly userRepository: Repository<UserEntity>,
     @InjectRepository(CommentEntity, WRITE_CONNECTION)
     private readonly commentRepository: Repository<CommentEntity>,
+    @Inject(ARTICLE_RMQ_CLIENT)
+    private readonly articleRmqClient: ClientProxy,
 
-    private readonly articleService: ArticleService,
-    private readonly publisher: PublisherService
-  ) {}
+    private readonly articleService: ArticleService
+  ) {
+    this.articleRmqClient.connect();
+  }
 
   async execute({
     userId,
@@ -55,10 +57,10 @@ export class CreateCommentCommandHandler
       await this.commentRepository.save(comment);
 
       if (comment) {
-        this.publisher.publish(ARTICLE_QUEUE, {
-          type: MessageType.COMMENT_CREATED,
-          payload: { comment },
-        });
+        this.articleRmqClient.emit<any, IPayloadCommentCreated>(
+          { cmd: MessageCmd.COMMENT_CREATED },
+          { comment }
+        );
       }
 
       const commentRO = this.articleService.buildCommentRO(comment);