如何使用 TypeScript 和 Sequelize

Question

我已经使用 Fastify 用 Node、PostgreSQL、Sequelize 编写了我的服务器应用程序。

现在我想使用 TypeScript。谁能告诉我如何开始使用 TypeScript 重写我的服务器应用程序。

Answer 1

您应该尽可能避免使用装饰器，它们不是 ECMAScript 标准。他们甚至被认为是遗产。这就是为什么我要向你展示如何将 sequelize 与 typescript 一起使用。

我们只需要关注文档：https://sequelize.org/v5/manual/typescript.html，但不是很清楚，或者至少对我来说不是很清楚。我花了一段时间才明白。

上面说你需要安装这棵树的东西

 * @types/node
 * @types/validator // this one is not need it
 * @types/bluebird

npm i -D @types/node @types/bluebird

然后让我们假设您的项目如下所示：

myProject
--src
----models
------index.ts
------user-model.ts
------other-model.ts
----controllers
----index.ts
--package.json

让我们先创建用户模型

`./src/models/user-model.ts`
import { BuildOptions, DataTypes, Model, Sequelize } from "sequelize";

export interface UserAttributes {
    id: number;
    name: string;
    email: string;
    createdAt?: Date;
    updatedAt?: Date;
}
export interface UserModel extends Model<UserAttributes>, UserAttributes {}
export class User extends Model<UserModel, UserAttributes> {}

export type UserStatic = typeof Model & {
    new (values?: object, options?: BuildOptions): UserModel;
};

export function UserFactory (sequelize: Sequelize): UserStatic {
    return <UserStatic>sequelize.define("users", {
        id: {
            type: DataTypes.INTEGER,
            autoIncrement: true,
            primaryKey: true,
        },
        email: {
            type: DataTypes.STRING,
            allowNull: false,
            unique: true,
        },
        name: {
            type: DataTypes.STRING,
            allowNull: false,
        },
        createdAt: {
            type: DataTypes.DATE,
            allowNull: false,
            defaultValue: DataTypes.NOW,
        },
        updatedAt: {
            type: DataTypes.DATE,
            allowNull: false,
            defaultValue: DataTypes.NOW,
        },
    });
}

现在只是为了玩箭头，让我们创建 another-model.ts

`./src/models/another-model.ts`

import { BuildOptions, DataTypes, Model, Sequelize } from "sequelize";

export interface SkillsAttributes {
    id: number;
    skill: string;
    createdAt?: Date;
    updatedAt?: Date;
}
export interface SkillsModel extends Model<SkillsAttributes>, SkillsAttributes {}
export class Skills extends Model<SkillsModel, SkillsAttributes> {}

export type SkillsStatic = typeof Model & {
    new (values?: object, options?: BuildOptions): SkillsModel;
};

export function SkillsFactory (sequelize: Sequelize): SkillsStatic {
    return <SkillsStatic>sequelize.define("skills", {
        id: {
            type: DataTypes.INTEGER,
            autoIncrement: true,
            primaryKey: true,
        },
        skill: {
            type: DataTypes.STRING,
            allowNull: false,
            unique: true,
        },
        createdAt: {
            type: DataTypes.DATE,
            allowNull: false,
            defaultValue: DataTypes.NOW,
        },
        updatedAt: {
            type: DataTypes.DATE,
            allowNull: false,
            defaultValue: DataTypes.NOW,
        },
    });
}

我们的实体已经完成。现在是数据库连接。

open ./src/models/index.ts 我们要放置 seqelize 实例的地方

`./src/models/index.ts`

import * as sequelize from "sequelize";
import {userFactory} from "./user-model";
import {skillsFactory} from "./other-model";

export const dbConfig = new sequelize.Sequelize(
    (process.env.DB_NAME = "db-name"),
    (process.env.DB_USER = "db-user"),
    (process.env.DB_PASSWORD = "db-password"),
    {
        port: Number(process.env.DB_PORT) || 54320,
        host: process.env.DB_HOST || "localhost",
        dialect: "postgres",
        pool: {
            min: 0,
            max: 5,
            acquire: 30000,
            idle: 10000,
        },
    }
);

// SOMETHING VERY IMPORTANT them Factory functions expect a
// sequelize instance as parameter give them `dbConfig`

export const User = userFactory(dbConfig);
export const Skills = skillsFactory(dbConfig);

// Users have skills then lets create that relationship

User.hasMay(Skills);

// or instead of that, maybe many users have many skills
Skills.belongsToMany(Users, { through: "users_have_skills" });

// the skill is the limit!

在我们的 index.ts 上添加，如果你只是想打开连接

  db.sequelize
        .authenticate()
        .then(() => logger.info("connected to db"))
        .catch(() => {
            throw "error";
        });

或者如果你想创建他们的表

  db.sequelize
        .sync()
        .then(() => logger.info("connected to db"))
        .catch(() => {
            throw "error";
        });

这样的

 
import * as bodyParser from "body-parser";
import * as express from "express";
import { dbConfig } from "./models";
import { routes } from "./routes";
import { logger } from "./utils/logger";
import { timeMiddleware } from "./utils/middlewares";

export function expressApp () {
    dbConfig
        .authenticate()
        .then(() => logger.info("connected to db"))
        .catch(() => {
            throw "error";
        });

    const app: Application = express();
    if (process.env.NODE_ENV === "production") {
        app.use(require("helmet")());
        app.use(require("compression")());
    } else {
        app.use(require("cors")());
    }

    app.use(bodyParser.json());
    app.use(bodyParser.urlencoded({ extended: true, limit: "5m" }));
    app.use(timeMiddleware);
    app.use("/", routes(db));

    return app;
}

再一次，天空是极限。 如果您这样做，您将拥有自动完成的所有功能。 这里是一个例子：https://github.com/EnetoJara/resume-app

Answer 2

使用 sequelize-typescript。将您的表和视图转换为扩展模型对象的类。

在类中使用注释来定义您的表格。

import {Table, Column, Model, HasMany} from 'sequelize-typescript';
 
@Table
class Person extends Model<Person> {
 
  @Column
  name: string;
 
  @Column
  birthday: Date;
 
  @HasMany(() => Hobby)
  hobbies: Hobby[];
}

通过创建对象来创建与数据库的连接：

const sequelize = new Sequelize(configuration...). 

然后将您的表注册到此对象。

sequelize.add([Person])

如需进一步参考，请查看此模块。 Sequelize-Typescript