MySQL Integration

DolphJS provides first-class support for MySQL databases. While you can use any ORM you prefer, the framework is heavily optimized for seamless integration with Sequelize through the auto-initialization sequence and the @InjectMySQL decorator.

Configuration

To connect to MySQL, you define the connection parameters in your dolph_config.yaml. The framework will read this file and attempt to establish a connection before starting the server.

database:
  mysql:
    host: localhost
    user: root
    password: my_secure_password
    database: dolph_db

Defining the Model (Sequelize)

Let’s create a Sequelize model for a User.

import { DataTypes, Model } from 'sequelize';
// Note: Assuming you export the sequelize instance from a central db file
// or DolphJS provides it. In standard DolphJS, you often define models
// and let the framework or your db initializer sync them.
import { sequelize } from '../db';

export class UserModel extends Model {
  public id!: number;
  public username!: string;
  public email!: string;
}

UserModel.init(
  {
    id: {
      type: DataTypes.INTEGER.UNSIGNED,
      autoIncrement: true,
      primaryKey: true,
    },
    username: {
      type: new DataTypes.STRING(128),
      allowNull: false,
    },
    email: {
      type: new DataTypes.STRING(128),
      allowNull: false,
      unique: true,
    },
  },
  {
    tableName: 'users',
    sequelize, // Pass the connection instance
  }
);

Injecting the Model

To keep your business logic clean, use Dependency Injection to provide the model to your Service.

import { DolphServiceHandler } from '@dolphjs/dolph/classes';
import { Dolph } from '@dolphjs/dolph/common';
import { InjectMySQL } from '@dolphjs/dolph/decorators';
import { ModelStatic, Model as SqlModel } from 'sequelize';
import { UserModel } from './user.model';

@InjectMySQL('userModel', UserModel)
export class UserService extends DolphServiceHandler<Dolph> {
  // TypeScript declaration matching the string in @InjectMySQL
  userModel!: ModelStatic<SqlModel<any, any>>;

  constructor() {
    super('userService');
  }

  async createUser(data: { username: string; email: string }) {
    // We now have full access to Sequelize methods on this.userModel
    const user = await this.userModel.create(data);
    return user;
  }

  async findByEmail(email: string) {
    return await this.userModel.findOne({ where: { email } });
  }
}