Sequelize + Decorators = ❤

A proof of concept for using Sequelize with decorators.

• Usage with TypeScript
• Usage with Babel

Usage with TypeScript

Installation

npm install --save sequelize sequelize-decorators

Add to your tsconfig.json:

"experimentalDecorators": true,
"emitDecoratorMetadata": true

The second setting lets sequelize-decorators infer the type of attributes from the type declaration.

Example:

import {Sequelize, Model, DataTypes} from 'sequelize'
import {Options, Attribute} from 'sequelize-decorators'
 
const sequelize = new Sequelize(process.env.DB)
 
@Options({
    sequelize,
    tableName: 'users'
})
export class User extends Model {
 
    @Attribute({
        type: DataTypes.STRING,
        primaryKey: true
    })
    public username: string;
 
    @Attribute(DataTypes.STRING)
    public firstName: string;
 
    @Attribute() // Type is inferred as DataTypes.STRING
    public lastName: string;
 
    get fullName(): string {
        return this.firstName + ' ' + this.lastName;
    }
 
    set fullName(fullName: string) {
        const names = fullName.split(' ');
        this.lastName = names.pop();
        this.firstName = names.join(' ');
    }
}

The @Options decorator is required and must include the sequelize option (the connection to use).

Type inference

TypeScript type	Sequelize data type
string	STRING
number	INTEGER
Date	DATE
Buffer	BLOB

Usage with Babel

Installation

npm install --save sequelize sequelize-decorators
npm install --save-dev babel-plugin-transform-decorators-legacy

Add to your .babelrc:

"plugins": ["transform-decorators-legacy"]

Example:

import {Sequelize, Model, DataTypes} from 'sequelize'
import {Options, Attributes} from 'sequelize-decorators'
 
const sequelize = new Sequelize(process.env.DB)
 
@Options({
    sequelize,
    tableName: 'users'
})
@Attributes({
    username: {
        type: DataTypes.STRING,
        primaryKey: true
    },
    lastName: DataTypes.STRING,
    firstName: DataTypes.STRING,
})
export class User extends Model {
 
    get fullName(): string {
        return this.firstName + ' ' + this.lastName;
    }
 
    set fullName(fullName: string) {
        const names = fullName.split(' ');
        this.lastName = names.pop();
        this.firstName = names.join(' ');
    }
}

The @Options decorator is required and must include the sequelize option (the connection to use).