[NestJS] 5. DB와 TypeORM 연동

mysql -u root -p

create database board_app;

npm install mysql2

npm install dotenv @nestjs/config

import * as dotenv from 'dotenv'; dotenv.config(); export const databaseConfig = { host: process.env.DB_HOST, user: process.env.DB_USER, password: process.env.DB_PW, port: +process.env.DB_PORT, //+는 문자->숫자로 바꿔줌 database: process.env.DB_NAME, connectionLimit: 10, insecureAuth: true, };

DB_HOST="localhost" DB_USER="root" DB_PW="1234" DB_PORT=3306 DB_NAME="board_app"

import { Module } from '@nestjs/common'; import { BoardsModule } from './boards/boards.module'; import { ConfigModule } from '@nestjs/config'; import { databaseConfig } from './configs/database.config'; @Module({ imports: [ ConfigModule.forRoot(), BoardsModule ], controllers: [], providers: [ { provide : 'DATABASE_CONFIG', useValue: databaseConfig } ], exports: ['DATABASE_CONFIG'] }) export class AppModule {}

import { Module } from '@nestjs/common'; import { BoardsController } from './boards.controller'; import { BoardsService } from './boards.service'; import { BoardsRepository } from './boards.repository'; @Module({ controllers: [BoardsController], providers: [BoardsService, BoardsRepository] }) export class BoardsModule {}

import { BadRequestException, Injectable, InternalServerErrorException, NotFoundException } from '@nestjs/common'; import { Board } from './boards.entity'; import { BoardStatus } from './boards-status.enum'; import { CreateBoardDto } from './dto/create-board.dto'; import { UpdateBoardDto } from './dto/update-board.dto'; import { BoardsRepository } from './boards.repository'; @Injectable() export class BoardsService { // DB Access (Repository 계층) constructor(private boardsRepository: BoardsRepository) {} // 게시글 조회 기능 async getAllBoards(): Promise<Board[]> { const foundBoards = await this.boardsRepository.findAll(); // 데이터베이스에서 모든 게시글을 가져오는 메서드 return foundBoards; // boards가 undefined일 경우 오류 발생 } ... // 게시글 작성 기능 async createBoard(createBoardDto: CreateBoardDto): Promise<string> { const { author, title, contents } = createBoardDto; // 구조분해할당 표현식 권장됨 if (!author || !title || !contents) { throw new BadRequestException('Author, title, and contents must be provided'); } const newBoard: Board = { id: 0, // Temporary ID author, // 구조분해전 기존 표현으로는 author: createBoardDto.author title, // 구조분해전 기존 표현으로는 author: createBoardDto.title contents, // 구조분해전 기존 표현으로는 author: createBoardDto.contents status: BoardStatus.PUBLIC, }; const message = await this.boardsRepository.saveBoard(newBoard); return message; } ... }

import { createPool, Pool } from 'mysql2/promise'; // mysql2/promise에서 임포트 import { databaseConfig } from '../configs/database.config'; // 데이터베이스 설정 임포트 import { Injectable, InternalServerErrorException } from '@nestjs/common'; import { Board } from './boards.entity'; @Injectable() export class BoardsRepository { private connectionPool: Pool; constructor() { this.connectionPool = createPool(databaseConfig); this.connectionPool.getConnection() .then(() => console.log('Database connected successfully')) .catch(err => console.error('Database connection failed:', err)); } async findAll(): Promise<Board[]> { const selectQuery = `SELECT * FROM board`; try { const [results] = await this.connectionPool.query(selectQuery); return results as Board[] || []; } catch (err) { throw new InternalServerErrorException('Database query failed', err); } } async saveBoard(board: Board): Promise<string> { const insertQuery = `INSERT INTO board (author, title, contents, status) VALUES (?, ?, ?, ?)`; try { const result = await this.connectionPool.query(insertQuery, [board.author, board.title, board.contents, board.status]); const message = 'Article created successfully.' return message; } catch (err) { throw new InternalServerErrorException('Database query failed', err); } } }

import { Body, Controller, Delete, Get, Param, ParseEnumPipe, Patch, Post, Put, Query, UsePipes, ValidationPipe } from '@nestjs/common'; import { BoardsService } from './boards.service'; import { Board } from './boards.entity'; import { CreateBoardDto } from './dto/create-board.dto'; import { BoardStatus } from './boards-status.enum'; import { UpdateBoardDto } from './dto/update-board.dto'; import { BoardStatusValidationPipe } from './pipes/board-status-validation.pipe'; @Controller('api/boards') @UsePipes(ValidationPipe) export class BoardsController { // 생성자 주입 constructor(private boardsService: BoardsService){} // 게시글 조회 기능 @Get('/') async getAllBoards(): Promise<Board[]> { return await this.boardsService.getAllBoards(); // 비동기적으로 게시글 가져오기 } ... // 게시글 작성 기능 @Post('/') async createBoard(@Body() createBoardDto: CreateBoardDto): Promise<string> { return await this.boardsService.createBoard(createBoardDto); } ... }

npm i @nestjs/typeorm typeorm

import { TypeOrmModuleOptions } from "@nestjs/typeorm"; import * as dotenv from 'dotenv'; dotenv.config(); export const typeOrmConfig: TypeOrmModuleOptions = { type: 'mysql', // 사용할 데이터베이스 유형 (MySQL, PostgreSQL, SQLite 등) host: process.env.DB_HOST, // 데이터베이스 호스트 port: +process.env.DB_PORT, // 데이터베이스 포트 username: process.env.DB_USER, // 데이터베이스 사용자 이름 password: process.env.DB_PW, // 데이터베이스 비밀번호 database: process.env.DB_NAME, // 사용할 데이터베이스 이름 entities: [__dirname + '/../**/*.entity.{js,ts}'], // 엔티티 파일의 위치 synchronize: true, // 애플리케이션 실행 시 스키마를 동기화할지 여부 (개발 중에만 true로 설정) logging: true, // SQL 쿼리 로그를 출력할지 여부 };

import { Module } from '@nestjs/common'; import { BoardsController } from './boards.controller'; import { BoardsService } from './boards.service'; import { TypeOrmModule } from '@nestjs/typeorm'; import { Board } from './boards.entity'; @Module({ imports: [ TypeOrmModule.forFeature([Board]), // Board 엔터티를 TypeORM 모듈에 등록 ], controllers: [BoardsController], providers: [BoardsService] }) export class BoardsModule {}

import { Module } from '@nestjs/common'; import { BoardsModule } from './boards/boards.module'; import { TypeOrmModule } from '@nestjs/typeorm'; import { typeOrmConfig } from './configs/typeorm.config'; @Module({ imports: [ TypeOrmModule.forRoot(typeOrmConfig), BoardsModule], }) export class AppModule {}

import { Column, Entity, PrimaryGeneratedColumn } from "typeorm"; import { BoardStatus } from "./boards-status.enum"; @Entity() export class Board { @PrimaryGeneratedColumn() id: number; @Column() author: string; @Column() title: string; @Column() contents: string; @Column() status: BoardStatus; }

import { Injectable, NotFoundException } from '@nestjs/common'; import { Board } from './board.entity'; import { BoardStatus } from "./board-status.enum"; import { InjectRepository } from '@nestjs/typeorm'; import { Repository } from 'typeorm'; import { UpdateBoardDto } from './dto/update-board.dto'; import { CreateBoardDto } from './dto/create-board.dto'; @Injectable() export class BoardsService { constructor( @InjectRepository(Board) private boardsRepository: Repository<Board> ){} // 게시글 작성 async createBoard(createBoardDto: CreateBoardDto): Promise<Board> { ...

npm start run:dev

use board_app;

desc boards;