升级TypeORM至0.3.7遇类型错误：如何按moment.Moment类型排序？

问题 #

将TypeORM从0.2.45版本升级到0.3.7版本后，以下查询代码中的createdAt字段出现类型错误（升级前可正常运行）：

const userTotalEvent = await EventRepository.find({
    where: {
        user: { id: user.id },
        type,
        invitationId
    },
    order: {
        createdAt: 'DESC'
    }
});

错误提示：

Type 'string' is not assignable to type 'FindOptionsOrder'.

相关实体及基类定义如下：
Event实体：

@Entity('event')
export default class Event extends BaseEntity {
  @PrimaryGeneratedColumn()
  public id!: number;

  @ManyToOne(() => User, (user: User) => user.event)
  public user!: User;

  @Column({ type: 'int' })
  public verificationAttempts!: number;
}

BaseEntity基类：

export default class BaseEntity {
  @Column({ type: 'datetime', transformer: datetimeSerializer() })
  @Transform(momentToString())
  public readonly createdAt: moment.Moment;

  @Column({ type: 'datetime', transformer: datetimeSerializer() })
  @Transform(momentToString())
  public updatedAt: moment.Moment;

  constructor() {
    super();
    this.createdAt = moment();
    this.updatedAt = moment();
  }
}

解决方案 #

方法1：显式指定排序值类型 #

给createdAt的排序值指定FindOptionsOrderValue类型，绕过TypeScript的类型校验：

import { FindOptionsOrderValue } from "typeorm";

const userTotalEvent = await EventRepository.find({
    where: {
        user: { id: user.id },
        type,
        invitationId
    },
    order: {
        createdAt: 'DESC' as FindOptionsOrderValue
    }
});

方法2：用类型定义约束查询选项 #

将查询选项变量声明为FindManyOptions<Event>类型，让TypeORM正确推断排序字段的合法值：

import { FindManyOptions } from "typeorm";

const options: FindManyOptions<Event> = {
    where: {
        user: { id: user.id },
        type,
        invitationId
    },
    order: {
        createdAt: 'DESC'
    }
};
const userTotalEvent = await EventRepository.find(options);

方法3：兼容日期字段的类型声明 #

修改BaseEntity中日期字段的类型，添加string类型兼容，让排序字符串能被类型系统识别：

export default class BaseEntity {
  @Column({ type: 'datetime', transformer: datetimeSerializer() })
  @Transform(momentToString())
  public readonly createdAt: moment.Moment | string;

  @Column({ type: 'datetime', transformer: datetimeSerializer() })
  @Transform(momentToString())
  public updatedAt: moment.Moment | string;

  constructor() {
    super();
    this.createdAt = moment();
    this.updatedAt = moment();
  }
}

方法4：改用QueryBuilder构建查询 #

使用TypeORM的QueryBuilder替代find方法，类型推断更精准，同时也能灵活控制查询逻辑：

const userTotalEvent = await EventRepository.createQueryBuilder('event')
    .where('event.userId = :userId', { userId: user.id })
    .andWhere('event.type = :type', { type })
    .andWhere('event.invitationId = :invitationId', { invitationId })
    .orderBy('event.createdAt', 'DESC')
    .getMany();

内容的提问来源于stack exchange，提问作者Tin Yu