Nest 复杂查询示例解析

  @Post()
  @Roles(Role.Admin, Role.SuperAdmin)
  async pageQuery(@Body() dto: QueryUserDto) {
    const res = await this.userService.pageQuery(dto);
    return successResult(res);
  }

// BaseQueryDto.ts
import { IsNotEmpty, IsNumber } from 'class-validator';
export class BaseQueryDto {
  @IsNotEmpty()
  @IsNumber()
  page: number;
  @IsNotEmpty()
  @IsNumber()
  pageSize: number;
}
// QueryUserDto.ts
export class QueryUserDto extends BaseQueryDto {
  username: string;
}

// user.service.ts
async pageQuery(dto: QueryUserDto) {
    const { username, pageSize, page } = dto;
    // 筛选状态为正常的数据
    const queryFilter: any = { status: DATA_STATUS.NORMAL };
    if (username) {
      // 模糊查询 username
      queryFilter.username = Like(`%${username}%`);
    }
    const res = await this.userRepository.findAndCount({
      // 查询条件
      where: queryFilter,
      // 排序
      order: { updateTime: 'DESC' },
      // offset，分页的偏移量
      skip: (page - 1) * pageSize,
      // 每页条数
      take: pageSize,
      // 是否缓存
      cache: true,
    });
    return loadPageQueryResult(res, pageSize);
  }
// 拼接返回结果的数据结构
export function loadPageQueryResult(findAndCountRes: any, pageSize: number) {
  const list = findAndCountRes[0];
  const totalCount = findAndCountRes[1];
  const totalPage = Math.ceil(totalCount / pageSize);
  return {
    list,
    totalCount,
    totalPage,
  };
}

{
  status: DATA_STATUS.NORMAL,
  username: Like(`%${username}%`)
}