在Ts.ED项目中使用TypeORM进行数据库操作-优快云博客

本文链接：https://blog.youkuaiyun.com/gitblog_00547/article/details/148755990

在Ts.ED项目中使用TypeORM进行数据库操作

tsed :triangular_ruler: Ts.ED is a Node.js and TypeScript framework on top of Express to write your application with TypeScript (or ES6). It provides a lot of decorators and guideline to make your code more readable and less error-prone. ⭐️ Star to support our work! 项目地址: https://gitcode.com/gh_mirrors/ts/tsed

TypeORM是一个优秀的关系型数据库ORM框架，而Ts.ED是一个基于TypeScript和Express的现代化Web框架。本文将详细介绍如何在Ts.ED项目中集成和使用TypeORM进行数据库操作。

TypeORM基础概念

在开始之前，我们先了解几个TypeORM的核心概念：

DataSource：数据源，代表与数据库的连接
Entity：实体类，映射数据库表结构
Repository：仓库模式，提供对特定实体的CRUD操作

初始化TypeORM数据源

在Ts.ED中初始化TypeORM数据源有两种方式：

1. 使用Ts.ED CLI生成

Ts.ED CLI提供了便捷的命令行工具来生成TypeORM数据源：

tsed generate

选择TypeORM DataSource选项，然后按照向导完成配置。

2. 手动创建数据源

你也可以手动创建数据源配置：

import {registerProvider} from "@tsed/di";
import {DataSource} from "typeorm";
import {Logger} from "@tsed/logger";
import {User} from "../entities/User";

export const MYSQL_DATA_SOURCE = Symbol.for("MySqlDataSource");
export const MysqlDataSource = new DataSource({
  type: "mysql",
  entities: [User],
  host: "localhost",
  port: 3306,
  username: "test",
  password: "test",
  database: "test"
});

registerProvider<DataSource>({
  provide: MYSQL_DATA_SOURCE,
  type: "typeorm:datasource",
  deps: [Logger],
  async useAsyncFactory(logger: Logger) {
    await MysqlDataSource.initialize();
    logger.info("Connected with typeorm to database: MySQL");
    return MysqlDataSource;
  },
  hooks: {
    $onDestroy(dataSource) {
      return dataSource.isInitialized && dataSource.close();
    }
  }
});

定义实体模型

在Ts.ED中定义TypeORM实体时，可以同时使用Ts.ED的装饰器来定义JSON Schema，这样同一个模型可以用于：

数据库表结构映射
API请求/响应数据验证
Swagger文档生成

import {Column, Entity, PrimaryGeneratedColumn} from "typeorm";
import {Required, MaxLength, MinLength, Email, Property} from "@tsed/schema";

@Entity()
export class User {
  @PrimaryGeneratedColumn()
  @Property()
  id: number;

  @Column()
  @Required()
  @MinLength(3)
  @MaxLength(50)
  firstName: string;

  @Column()
  @Required()
  @MinLength(3)
  @MaxLength(50)
  lastName: string;

  @Column()
  @Required()
  @Email()
  email: string;
}

在控制器中使用TypeORM

定义好实体后，我们可以在控制器中直接使用：

import {BodyParams} from "@tsed/platform-params";
import {Get, Post} from "@tsed/schema";
import {Controller, Inject} from "@tsed/di";
import {MYSQL_DATA_SOURCE} from "../datasources/MysqlDataSource";
import {User} from "../entities/User";

@Controller("/users")
export class UsersCtrl {
  @Inject(MYSQL_DATA_SOURCE)
  protected mysqlDataSource: DataSource;

  @Post("/")
  create(@BodyParams() user: User): Promise<User> {
    return this.mysqlDataSource.manager.save(User, user);
  }

  @Get("/")
  getList(): Promise<User[]> {
    return this.mysqlDataSource.manager.find(User);
  }
}

创建自定义Repository

为了更好的组织代码，我们可以创建自定义Repository：

import {Injectable} from "@tsed/di";
import {DataSource} from "typeorm";
import {MySqlDataSource} from "../datasources/MySqlDataSource";
import {User} from "../entities/User";

export const UserRepository = MySqlDataSource.getRepository(User).extend({
  findByName(firstName: string, lastName: string) {
    return this.createQueryBuilder("user")
      .where("user.firstName = :firstName", {firstName})
      .andWhere("user.lastName = :lastName", {lastName})
      .getMany();
  }
});

export const USER_REPOSITORY = Symbol.for("UserRepository");
export type USER_REPOSITORY = typeof UserRepository;

registerProvider({
  provide: USER_REPOSITORY,
  useValue: UserRepository
});

然后在控制器中注入使用：

import {BodyParams} from "@tsed/platform-params";
import {Get, Post} from "@tsed/schema";
import {Controller, Inject} from "@tsed/di";
import {USER_REPOSITORY} from "../repositories/UserRepository";
import {User} from "../entities/User";

@Controller("/users")
export class UsersCtrl {
  @Inject(USER_REPOSITORY)
  protected repository: USER_REPOSITORY;

  @Post("/")
  create(@BodyParams() user: User): Promise<User> {
    return this.repository.save(user);
  }

  @Get("/")
  getList(): Promise<User[]> {
    return this.repository.find();
  }

  @Get("/by-name")
  getByName(): Promise<User[]> {
    return this.repository.findByName("John", "Doe");
  }
}

多数据源管理

如果你的应用需要连接多个数据库，可以创建多个DataSource实例，并通过服务统一管理：

import {Inject, Injectable, InjectorService} from "@tsed/di";

@Injectable()
export class DataSourcesService {
  @Inject()
  protected injector: InjectorService;

  getDataSources() {
    return this.injector.getAll("typeorm:datasource");
  }
}