MongoDB Integration

MongoDB is arguably the most popular NoSQL database in the Node.js ecosystem. DolphJS offers zero-boilerplate auto-initialization for MongoDB when combined with the Mongoose ODM.

Configuration

Setting up MongoDB is as simple as adding the URL to your dolph_config.yaml.

database:
  mongo:
    url: mongodb://127.0.0.1:27017/dolph_app
    options:
      useNewUrlParser: true
      useUnifiedTopology: true

Securing your MongoDB URL: If you do not want to hardcode your MongoDB connection string in the dolph_config.yaml file, you can pass the value "sensitive" to the url field. DolphJS will then automatically check your .env file for a MONGO_URL key and use that instead!

database:
  mongo:
    url: sensitive

When you start your application using DolphFactory, DolphJS automatically establishes the Mongoose connection pool using the settings from dolph_config.yaml.

Programmatic Initialization (Alternative)

If you prefer to skip dolph_config.yaml or want to manually control the connection timing (e.g. for testing or complex setups), you can initialize the database programmatically using autoInitMongo from @dolphjs/packages.

import { autoInitMongo } from '@dolphjs/dolph/packages';

autoInitMongo({
  url: 'mongodb://127.0.0.1:27017/dolph_app',
  options: {
    useNewUrlParser: true,
    useUnifiedTopology: true,
  }
});

Defining the Schema

Create your Mongoose schema in a dedicated .model.ts file.

import { Schema, Document, model } from 'mongoose';

export interface IProduct extends Document {
  title: string;
  price: number;
  inStock: boolean;
}

const ProductSchema = new Schema(
  {
    title: { type: String, required: true },
    price: { type: Number, required: true },
    inStock: { type: Boolean, default: true },
  },
  { timestamps: true }
);

export const ProductModel = model<IProduct>('Product', ProductSchema);

Injecting the Model

Use the @InjectMongo decorator to inject the model into your Dolph Service. This pattern ensures your Service remains testable and decoupled.

import { DolphServiceHandler } from '@dolphjs/dolph/classes';
import { Dolph } from '@dolphjs/dolph/common';
import { InjectMongo } from '@dolphjs/dolph/decorators';
import { Model } from 'mongoose';
import { ProductModel, IProduct } from './product.model';

@InjectMongo('productModel', ProductModel)
export class ProductService extends DolphServiceHandler<Dolph> {
  // Ensure the property name exactly matches the string 'productModel'
  productModel!: Model<IProduct>;

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

  async addProduct(data: { title: string; price: number }) {
    // Utilize Mongoose's create method via the injected property
    const newProduct = await this.productModel.create(data);
    return newProduct;
  }

  async getAllProducts() {
    return await this.productModel.find({ inStock: true });
  }
}