Sequelize with Typescript(작성중)

sequelize에서 타입스크립트 사용

Sequelize는 런타임 속성 할당에 크게 의존하기 때문에 Typescript는 기본적으로 유용하지 않다.

모델을 작동 가능하게 하려면 상당한 양의 수동 유형 선언이 필요하다.

필요 패키지

• @types/node (this is universally required in node projects)
• @types/validator

사용

strict type-checking for attributes

import {
  Sequelize,
  Model,
  ModelDefined,
  DataTypes,
  HasManyGetAssociationsMixin,
  HasManyAddAssociationMixin,
  HasManyHasAssociationMixin,
  Association,
  HasManyCountAssociationsMixin,
  HasManyCreateAssociationMixin,
  Optional,
} from "sequelize";

const sequelize = new Sequelize("mysql://root:asd123@localhost:3306/mydb");

// 유저 모델 예시
// 인터페이스로 타입 지정
interface UserAttributes {
  id: number;
  name: string;
  preferredName: string | null;
}

// Some attributes are optional in `User.build` and `User.create` calls
interface UserCreationAttributes extends Optional<UserAttributes, "id"> {}

class User extends Model<UserAttributes, UserCreationAttributes>
  implements UserAttributes {
  public id!: number; // Note that the `null assertion` `!` is required in strict mode. // 느낌표 붙은 속성은 반드시 넣어야 되는 column
  public name!: string;
  public preferredName!: string | null; // for nullable fields

  // timestamps!
  public readonly createdAt!: Date;
  public readonly updatedAt!: Date;

  // Since TS cannot determine model association at compile time
  // we have to declare them here purely virtually
  // these will not exist until `Model.init` was called.
  public getProjects!: HasManyGetAssociationsMixin<Project>; // Note the null assertions!
  public addProject!: HasManyAddAssociationMixin<Project, number>;
  public hasProject!: HasManyHasAssociationMixin<Project, number>;
  public countProjects!: HasManyCountAssociationsMixin;
  public createProject!: HasManyCreateAssociationMixin<Project>;

  // You can also pre-declare possible inclusions, these will only be populated if you
  // actively include a relation.
  public readonly projects?: Project[]; // Note this is optional since it's only populated when explicitly requested in code

  public static associations: {
    projects: Association<User, Project>;
  };
}

Usage without strict types for attributes

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

const sequelize = new Sequelize("mysql://root:asd123@localhost:3306/mydb");

class User extends Model {
  public id!: number; // Note that the `null assertion` `!` is required in strict mode.
  public name!: string;
  public preferredName!: string | null; // for nullable fields
}

User.init(
  {
    id: {
      type: DataTypes.INTEGER.UNSIGNED,
      autoIncrement: true,
      primaryKey: true,
    },
    name: {
      type: new DataTypes.STRING(128),
      allowNull: false,
    },
    preferredName: {
      type: new DataTypes.STRING(128),
      allowNull: true,
    },
  },
  {
    tableName: "users",
    sequelize, // passing the `sequelize` instance is required
  }
);

async function doStuffWithUserModel() {
  const newUser = await User.create({
    name: "Johnny",
    preferredName: "John",
  });
  console.log(newUser.id, newUser.name, newUser.preferredName);

  const foundUser = await User.findOne({ where: { name: "Johnny" } });
  if (foundUser === null) return;
  console.log(foundUser.name);
}

참고 문헌

• sequelize 공식 문서 중 typescript 부분