【Nest教程】实现一个简单的用户增删改查功能

2021-02-03 11:13:41 浏览数 (1)

连接MySQL，实现一个简单的增删改查功能

前面几章我们讲了项目的初始，连接MySQL，这章我们主要实现增删改查接口，在src下新建user文件夹，我们的所有功能都写在这个文件夹下。

1 新建entity

项目开始配置连接数据库的时候，我们 synchronize 选择的事true，即使我们库里没有表，通过entity也可以自动生成表

代码语言：javascript复制
import { Column, Entity, PrimaryGeneratedColumn, BaseEntity } from 'typeorm';

/**
 * 列选项参考
 * https://typeorm.biunav.com/zh/entities.html#列选项
 **/
@Entity()
export class User extends BaseEntity {
  @PrimaryGeneratedColumn()
  id: number;

  @Column({ type: 'varchar', name: 'name', comment: '用户名' })
  name: string;

  @Column({ type: 'varchar', name: 'nickname', comment: '昵称' })
  nickname: string;

  @Column({ type: 'varchar', name: 'password', comment: '密码' })
  password: string;

  @Column({ type: 'varchar', length: 11, name: 'mobile', comment: '手机号' })
  mobile: string;

  @Column({ type: 'varchar', nullable: true, name: 'avatar', comment: '头像' })
  avatar: string;

  @Column({ type: 'varchar', default: '未知', name: 'gender', comment: '性别' })
  gender: string;

  @Column({
    type: 'varchar',
    default: '普通会员',
    name: 'user_level',
    comment: '用户级别',
  })
  userLevel: string;

  @Column({
    type: 'varchar',
    nullable: true,
    name: 'province',
    comment: '省份',
  })
  province: string;

  @Column({ type: 'varchar', nullable: true, name: 'city', comment: '城市' })
  city: string;

  @Column({ type: 'datetime', nullable: true, name: 'create_time' })
  createTime: number;

  @Column({ type: 'datetime', nullable: true, name: 'update_time' })
  updateTime: number;
}

上面的内容定义的是表的字段及字段类型等

2 新建controller

这里定义了四个路由，全部为post请求方式

代码语言：javascript复制
import { ApiTags, ApiParam, ApiQuery, ApiHeader } from '@nestjs/swagger';
import { Controller, Get, Post, Body, Logger } from '@nestjs/common';
import { UserService } from './user.service';
import { QueryUserDto } from './Dto/queryUser.dto';
import { AddUserDto } from './Dto/addUser.dto';
import { UpdateUserDto } from './Dto/updateUser.dto';
import { DeleteUserDto } from './Dto/deleteUser.dto';

/**
 *
 * @author lidonghui
 * @version 1
 * @date 2021/01/18 09:57
 */
@ApiTags('用户管理')
@Controller('user')
export class UserController {
  constructor(private readonly userService: UserService) {}

  /**
   * 用户管理-分页查询
   */
  @ApiQuery({
    name: 'name',
    description: '用户名',
  })
  @Post('/page')
  findAll(@Body() queryUserDto: QueryUserDto): Promise<{}> {
    Logger.log(`分页查询接收参数：${JSON.stringify(queryUserDto)}`);
    return this.userService.pageQuery(queryUserDto);
  }

  /**
   * 用户管理-增加用户
   */
  @Post('/add')
  addUser(@Body() addUserDto: AddUserDto): Promise<boolean> {
    Logger.log(`增加用户接收参数：${JSON.stringify(addUserDto)}`);
    return this.userService.save(addUserDto);
  }

  /**
   * 用户管理-编辑用户
   */
  @Post('/edit')
  updateUser(@Body() updateUserDto: UpdateUserDto): Promise<boolean> {
    Logger.log(`编辑用户接收参数：${JSON.stringify(updateUserDto)}`);
    return this.userService.save(updateUserDto);
  }

  /**
   * 用户管理-删除用户
   */
  @Post('/delete')
  deleteUser(@Body() deleteUserDto: DeleteUserDto): Promise<boolean> {
    Logger.log(`删除用户接收参数：${JSON.stringify(deleteUserDto)}`);
    return this.userService.delete(deleteUserDto);
  }
}

3 新建service

这里主要的实现是对库的操作，这里面就包含了增删改查

代码语言：javascript复制
import { Injectable, Logger } from '@nestjs/common';
import { InjectRepository } from '@nestjs/typeorm';
import { Repository } from 'typeorm';
import { User } from './user.entity';

@Injectable()
export class UserService {
  constructor(
    @InjectRepository(User)
    private readonly UserRepository: Repository<User>,
  ) {}

  private readonly User: User[] = [];

  // 分页查询
  async pageQuery(parameter: any): Promise<any> {
    Logger.log(`请求参数：${JSON.stringify(parameter)}`);

    // 定义返回格式
    let result = {
      pageNo: Number(parameter.pageNo),
      pageSize: Number(parameter.pageSize),
      totalPage: 0,
      totalRows: 0,
      rows: [],
    };

    // 返回条数
    let SQLwhere: any = {};
    if (parameter.name != undefined) {
      SQLwhere.name = parameter.name;
    }
    result.rows = await this.UserRepository.find({
      where: SQLwhere,
      order: {
        id: 'DESC',
      },
      skip: (parameter.pageNo - 1) * Number(parameter.pageSize), // 分页，跳过几项
      take: parameter.pageSize, // 分页，取几项
      cache: true,
    });

    // 总条数
    result.totalRows = await this.UserRepository.count();

    // 总页数
    result.totalPage = Math.ceil(
      (await this.UserRepository.count()) / parameter.pageSize,
    );

    return result;
  }

  // 增加/更新
  async save(parameter: any): Promise<boolean> {
    Logger.log(`请求参数：${JSON.stringify(parameter)}`);
    try {
      let a = await this.UserRepository.save(parameter);
      return true;
    } catch (error) {
      Logger.log(`请求失败：${JSON.stringify(error)}`);
      return false;
    }
  }

  // 删除
  async delete(ids: any): Promise<boolean> {
    Logger.log(`请求参数：${JSON.stringify(ids)}`);
    try {
      let a = await this.UserRepository.delete(ids.id);
      Logger.log(`删除返回数据：${JSON.stringify(a)}`);
      if (a.affected == 0) {
        return false;
      } else {
        return true;
      }
    } catch (error) {
      return false;
    }
  }
}

4 新建module

代码语言：javascript复制
import { Module } from '@nestjs/common';
import { UserService } from './user.service';
import { UserController } from './user.controller';

import { TypeOrmModule } from '@nestjs/typeorm';
import { User } from './user.entity';

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

5 新建Dto

Dto文件夹有四个文件，分别为addUser.dto.ts、deleteUser.dto.ts、queryUser.dto.ts和updateUser.dto.ts，这四个是查询及验证使用

1 addUser.dto.ts

代码语言：javascript复制
import { ApiProperty } from '@nestjs/swagger';
import { IsNotEmpty } from 'class-validator';
export class AddUserDto {
  @ApiProperty()
  @IsNotEmpty({ message: '用户名不为空' })
  readonly name: string;

  @ApiProperty()
  @IsNotEmpty({ message: '昵称不为空' })
  readonly nickname: string;

  @ApiProperty()
  @IsNotEmpty({ message: '密码不为空' })
  readonly password: string;

  @ApiProperty()
  @IsNotEmpty({ message: '手机号不为空' })
  readonly mobile: string;

  @ApiProperty()
  readonly avatar: string;

  @ApiProperty()
  readonly gender: string;

  @ApiProperty()
  readonly userLevel: string;

  @ApiProperty()
  readonly province: string;

  @ApiProperty()
  readonly city: string;
}

2 deleteUser.dto.ts

代码语言：javascript复制
import { ApiProperty } from '@nestjs/swagger';
import { IsNotEmpty, IsInt } from 'class-validator';
export class DeleteUserDto {
  @ApiProperty()
  @IsInt({ message: 'id应为数字' })
  @IsNotEmpty({ message: 'id不为空' })
  readonly id: number;
}

3 queryUser.dto.ts

代码语言：javascript复制
import { ApiProperty } from '@nestjs/swagger';
import { IsNotEmpty, Min, IsInt } from 'class-validator';
export class QueryUserDto {
  @ApiProperty()
  readonly name: string;

  @ApiProperty()
  @Min(1, { message: '分页不能小于1' })
  @IsInt({ message: '分页应为数字' })
  @IsNotEmpty({ message: '分页不能为空' })
  readonly pageNo: number;

  @ApiProperty()
  @Min(1, { message: '分页条数不能小于1' })
  @IsInt({ message: '分页条数应为数字' })
  @IsNotEmpty({ message: '分页条数不能为空' })
  readonly pageSize: number;
}

4 updateUser.dto.ts

代码语言：javascript复制
import { ApiProperty } from '@nestjs/swagger';
import { IsNotEmpty, IsInt } from 'class-validator';
export class UpdateUserDto {
  @ApiProperty()
  @IsInt({ message: 'id应为数字' })
  @IsNotEmpty({ message: 'id不为空' })
  readonly id: number;

  @ApiProperty()
  readonly name: string;

  @ApiProperty()
  readonly nickname: string;

  @ApiProperty()
  readonly password: string;

  @ApiProperty()
  readonly mobile: string;

  @ApiProperty()
  readonly avatar: string;

  @ApiProperty()
  readonly gender: string;

  @ApiProperty()
  readonly userLevel: string;

  @ApiProperty()
  readonly province: string;

  @ApiProperty()
  readonly city: string;
}

6 运行项目

上面的是全部的配置，主要因为是此项目没有开源，所以代码全部复制，基本能运行。最后结果

typescript 数据库 云数据库SQLServer sql linux

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