nestjs学习（三）：连接数据库实现简单增删查改

import { Module } from '@nestjs/common';
import { AppController } from './app.controller';
import { AppService } from './app.service';
import { UserModule } from './user/user.module';
import { TypeOrmModule } from '@nestjs/typeorm';

@Module({
  imports: [ TypeOrmModule.forRoot({
    type: 'mysql', // 数据库类型
    host: 'localhost', // 数据库主机
    port: 3306, // 数据库端口
    username: 'root', // 数据库用户名
    password: 'root', // 数据库密码
    database: 'nest_demo', // 数据库名称
    entities: [__dirname + '/**/*.entity{.ts,.js}'], // 数据库实体文件
    synchronize: true, // 是否自动同步实体
    logging: true, // 是否打印日志
    retryDelay: 500, // 重试连接间隔
    retryAttempts: 10, // 重试连接次数
    autoLoadEntities: true, // 自动加载实体

  }), UserModule],
  controllers: [AppController],
  providers: [AppService],
})
export class AppModule {}

import { Column, Entity, PrimaryGeneratedColumn } from "typeorm";

@Entity() // 表名
export class User {
    @PrimaryGeneratedColumn() // 主键
    id: number;

    // @Column({ unique: true, length: 20, nullable: false }) // 列：必填 长度20  默认非空 唯一
    @Column()
    username: string;

    // @Column({ length: 20, nullable: false, select: false }) // 列：必填 长度20  默认非空 不显示
    @Column()
    password: string;

    @Column() // 列
    age: number;
}

import { Module } from '@nestjs/common';
import { UserService } from './user.service';
import { UserController } from './user.controller';
import { TypeOrmModule } from '@nestjs/typeorm';
import { User } from './entities/user.entity';

@Module({
  imports: [TypeOrmModule.forFeature([User])],
  controllers: [UserController],
  providers: [UserService],
})
export class UserModule {}

import { User } from './entities/user.entity';
import { Injectable } from '@nestjs/common';
import { CreateUserDto } from './dto/create-user.dto';
import { UpdateUserDto } from './dto/update-user.dto';
import { InjectRepository } from '@nestjs/typeorm';
import { Repository } from 'typeorm';
import { hash, verify } from '../utils/md5';

@Injectable()
export class UserService {
  // 注释：这里使用@InjectRepository 注解，注入User实体，使用Repository<User>
  constructor(
    @InjectRepository(User)
    private usersRepository: Repository<User>,
  ) { }
  async create(createUserDto: CreateUserDto) {
    // 对密码进行加密
    createUserDto.password = hash(createUserDto.password, process.env.MD5_SALT)
    // 前端传入的数据，保存到数据库中
    const user = await this.usersRepository.save(createUserDto) // 保存到数据库中
    const { password, ...userWithoutPassword } = user; // 删除密码
    return userWithoutPassword
  }

  async findAll() {
    // 查询所有用户
    return await this.usersRepository.find();
  }

  async findOne(id: number) {
    // 根据id查询用户
    const user = await this.usersRepository.findOneBy({ id })
    return user;
  }

  async update(id: number, updateUserDto: UpdateUserDto) {
    const user = await this.usersRepository.update(id, updateUserDto) // 更新
    return user;
  }

  async remove(id: number) {
    const user = await this.usersRepository.delete(id)
    return user;
  }
}

import { MD5 } from "crypto-js";

/**
 * @description: hash加密
 * @param {string} val 要加密的字符串
 * @param {*} salt 盐
 * @Author: clue
 */
export function hash(val: string, salt = "") {
    return MD5(`${val}${salt}`).toString();
}

/**
 * @description: 比对加密后的字符串
 * @param {string} val 要比对的字符串
 * @param {string} hashVal 加密后的字符串
 * @param {*} salt 盐
 * @Author: clue
 */
export function verify(val: string, hashVal: string, salt = "") {
    return hash(val, salt) === hashVal;
}

import { Controller, Get, Post, Body, Patch, Param, Delete, HttpStatus, HttpException } from '@nestjs/common';
import { UserService } from './user.service';
import { CreateUserDto } from './dto/create-user.dto';
import { UpdateUserDto } from './dto/update-user.dto';

@Controller('user')
export class UserController {
  constructor(private readonly userService: UserService) { }

  @Post()
  create(@Body() createUserDto: CreateUserDto) {
    return this.userService.create(createUserDto);
  }

  @Get()
  findAll() {
    const a = process.env.SALT
    return this.userService.findAll();
  }

  @Get(':id')
  findOne(@Param('id') id: string) {
    // 根据id查询用户
    const user = this.userService.findOne(+id)
    if (!user) {
      throw new HttpException('用户不存在', HttpStatus.NOT_FOUND)
    } else {
      return user
    }
  }

  @Patch(':id')
  update(@Param('id') id: string, @Body() updateUserDto: UpdateUserDto) {
    return this.userService.update(+id, updateUserDto);
  }

  @Delete(':id')
  remove(@Param('id') id: string) {
    return this.userService.remove(+id);
  }
}