服务(Service)

我们一般将业务逻辑写在Service层，Controller层只做参数校验、数据转换等操作，Service层做具体的业务逻辑处理。

cool-admin对基本的Service进行封装；

重写 CRUD

Controller的六个快速方法，add、update、delete、info、list、page，是通过调用一个通用的BaseService的方法实现，所以我们可以重写Service的方法来实现自己的业务逻辑。

示例

重写 add 方法

import { DemoGoodsEntity } from "./../entity/goods";
import { Provide } from "@midwayjs/core";
import { BaseService } from "@cool-midway/core";
import { InjectEntityModel } from "@midwayjs/typeorm";
import { Repository } from "typeorm";

/**
 * 商品示例
 */
@Provide()
export class DemoGoodsService extends BaseService {
  @InjectEntityModel(DemoGoodsEntity)
  demoGoodsEntity: Repository<DemoGoodsEntity>;

  /**
   * 新增
   * @param param
   * @returns
   */
  async add(param: any) {
    // 调用原本的add，如果不需要可以不用这样写，完全按照自己的新增逻辑写
    const result = await super.add(param);
    // 你自己的业务逻辑
    return result;
  }
}

记得在Controller上配置对应的Service才会使其生效

import { DemoGoodsService } from "../../service/goods";
import { DemoGoodsEntity } from "../../entity/goods";
import { Body, Inject, Post, Provide } from "@midwayjs/core";
import { CoolController, BaseController } from "@cool-midway/core";
import { InjectEntityModel } from "@midwayjs/typeorm";
import { Repository } from "typeorm";

/**
 * 测试
 */
@Provide()
@CoolController({
  api: ["add", "delete", "update", "info", "list", "page"],
  entity: DemoGoodsEntity,
  service: DemoGoodsService,
})
export class AppDemoGoodsController extends BaseController {}

普通查询(TypeOrm)

普通查询基于TypeOrm，点击查看官方详细文档

示例

import { DemoGoodsEntity } from "./../entity/goods";
import { Provide } from "@midwayjs/core";
import { BaseService } from "@cool-midway/core";
import { InjectEntityModel } from "@midwayjs/typeorm";
import { In, Repository } from "typeorm";

/**
 * 商品示例
 */
@Provide()
export class DemoGoodsService extends BaseService {
  @InjectEntityModel(DemoGoodsEntity)
  demoGoodsEntity: Repository<DemoGoodsEntity>;

  async typeorm() {
    // 新增单个，传入的参数字段在数据库中一定要存在
    await this.demoGoodsEntity.insert({ title: "xxx" });
    // 新增单个，传入的参数字段在数据库中可以不存在
    await this.demoGoodsEntity.save({ title: "xxx" });
    // 新增多个
    await this.demoGoodsEntity.save([{ title: "xxx" }]);
    // 查找单个
    await this.demoGoodsEntity.findOneBy({ id: 1 });
    // 查找多个
    await this.demoGoodsEntity.findBy({ id: In([1, 2]) });
    // 删除单个
    await this.demoGoodsEntity.delete(1);
    // 删除多个
    await this.demoGoodsEntity.delete([1]);
    // 根据ID更新
    await this.demoGoodsEntity.update(1, { title: "xxx" });
    // 根据条件更新
    await this.demoGoodsEntity.update({ price: 20 }, { title: "xxx" });
    // 多条件操作
    await this.demoGoodsEntity
      .createQueryBuilder()
      .where("id = :id", { id: 1 })
      .andWhere("price = :price", { price: 20 })
      .getOne();
  }
}

高级查询(SQL)

1、普通 SQL 查询

import { DemoGoodsEntity } from "./../entity/goods";
import { Provide } from "@midwayjs/core";
import { BaseService } from "@cool-midway/core";
import { InjectEntityModel } from "@midwayjs/typeorm";
import { Repository } from "typeorm";

/**
 * 商品示例
 */
@Provide()
export class DemoGoodsService extends BaseService {
  @InjectEntityModel(DemoGoodsEntity)
  demoGoodsEntity: Repository<DemoGoodsEntity>;

  /**
   * 执行sql
   */
  async sql(query) {
    return this.nativeQuery("select * from demo_goods a where a.id = ?", [
      query.id,
    ]);
  }
}

2、分页 SQL 查询

import { DemoGoodsEntity } from "./../entity/goods";
import { Provide } from "@midwayjs/core";
import { BaseService } from "@cool-midway/core";
import { InjectEntityModel } from "@midwayjs/typeorm";
import { Repository } from "typeorm";

/**
 * 商品示例
 */
@Provide()
export class DemoGoodsService extends BaseService {
  @InjectEntityModel(DemoGoodsEntity)
  demoGoodsEntity: Repository<DemoGoodsEntity>;

  /**
   * 执行分页sql
   */
  async sqlPage(query) {
    return this.sqlRenderPage(
      "select * from demo_goods ORDER BY id ASC",
      query,
      false
    );
  }
}

3、非 SQL 的分页查询

import { DemoGoodsEntity } from "./../entity/goods";
import { Provide } from "@midwayjs/core";
import { BaseService } from "@cool-midway/core";
import { InjectEntityModel } from "@midwayjs/typeorm";
import { In, Repository } from "typeorm";

/**
 * 商品示例
 */
@Provide()
export class DemoGoodsService extends BaseService {
  @InjectEntityModel(DemoGoodsEntity)
  demoGoodsEntity: Repository<DemoGoodsEntity>;

  /**
   * 执行entity分页
   */
  async entityPage(query) {
    const find = this.demoGoodsEntity.createQueryBuilder();
    find.where("id = :id", { id: 1 });
    return this.entityRenderPage(find, query);
  }
}

4、SQL 动态条件

分页查询和普通的 SQL 查询都支持动态条件，通过this.setSql(条件,sql语句,参数)来配置

import { DemoGoodsEntity } from "./../entity/goods";
import { Provide } from "@midwayjs/core";
import { BaseService } from "@cool-midway/core";
import { InjectEntityModel } from "@midwayjs/typeorm";
import { Repository } from "typeorm";

/**
 * 商品示例
 */
@Provide()
export class DemoGoodsService extends BaseService {
  @InjectEntityModel(DemoGoodsEntity)
  demoGoodsEntity: Repository<DemoGoodsEntity>;

  /**
   * 执行sql
   */
  async sql(query) {
    return this.nativeQuery(`
    select * from demo_goods a
      WHERE 1=1
      ${this.setSql(query.id, "and a.id = ?", [query.id])}
    ORDER BY id ASC
    `);
  }
}

修改之前(modifyBefore)

有时候我们需要在数据进行修改动作之前，对它进行一些处理，比如：修改密码时，需要对密码进行加密，这时候我们可以使用modifyBefore方法来实现

import { DemoGoodsEntity } from "./../entity/goods";
import { Provide } from "@midwayjs/core";
import { BaseService } from "@cool-midway/core";
import { InjectEntityModel } from "@midwayjs/typeorm";
import { Repository } from "typeorm";
import * as md5 from "md5";

/**
 * 商品示例
 */
@Provide()
export class DemoGoodsService extends BaseService {
  @InjectEntityModel(DemoGoodsEntity)
  demoGoodsEntity: Repository<DemoGoodsEntity>;

  /**
   * 修改之前
   * @param data
   * @param type
   */
  async modifyBefore(data: any, type: "delete" | "update" | "add") {
    if (type == "update") {
      data.password = md5(data.password);
    }
  }
}

修改之后(modifyAfter)

有时候我们需要在数据进行修改动作之后，对它进行一些处理，比如：修改完数据之后将它放入队列或者 ElasticSearch

import { DemoGoodsEntity } from "./../entity/goods";
import { Provide } from "@midwayjs/core";
import { BaseService } from "@cool-midway/core";
import { InjectEntityModel } from "@midwayjs/typeorm";
import { Repository } from "typeorm";
import * as md5 from "md5";

/**
 * 商品示例
 */
@Provide()
export class DemoGoodsService extends BaseService {
  @InjectEntityModel(DemoGoodsEntity)
  demoGoodsEntity: Repository<DemoGoodsEntity>;

  /**
   * 修改之后
   * @param data
   * @param type
   */
  async modifyAfter(data: any, type: "delete" | "update" | "add") {
    // 你想做的其他事情
  }
}

设置实体

Service与Service之间相互调用BaseService里的方法，有可能出现“未设置操作实体”的问题可以通过以下方式设置实体

建议

但是一般不建议这样做，因为这样会导致Service与Service耦合，不利于代码的维护，如果要操作对应的表直接在当前的Service注入对应的表操作即可

@Provide()
export class XxxService extends BaseService {
  @InjectEntityModel(XxxEntity)
  xxxEntity: Repository<XxxEntity>;

  @Init()
  async init() {
    await super.init();
    // 设置实体
    this.setEntity(this.xxxEntity);
  }
}

服务(Service) ​

重写 CRUD ​

普通查询(TypeOrm) ​

高级查询(SQL) ​

修改之前(modifyBefore) ​

修改之后(modifyAfter) ​

设置实体 ​