MongoDB

Typetta offers full support for MongoDB and all compatible document databases. Access to the database is developed using the official MongoDB Node Driver internally.

All the features of Typetta allow direct access to the driver, ensuring maximum flexibility and fast adoption of the features present in the latest versions of the database.

How to connect

In line with official documentation, connecting to an instance of MongoDB or to a replica set using the Node JS driver can be implemented as follows:

import { MongoClient } from "mongodb";

const uri = "mongodb+srv://sample-hostname:27017/?maxPoolSize=20&w=majority";
const client = new MongoClient(uri);

async function run() {
  try {
    await client.connect();
    const db = await client.db("dbname")
  } finally {
    await client.close();
  }
}
run().catch(console.dir);

Note that it is the driver that deals with the connection pooling, that is, each JS Node process usually has to make only one connection and take only one reference from the db that can then be reused in each call or procedure. Therefore, it is not recommended to make repeated connections.

Creation of the EntityManager

Unlike connection, the EntityManager can be instantiated multiple times and with different parameters. For example, it is advisable to create an EntityManager for each calling context (for example, each REST or GraphQL call).

The EntityManager requires as input a reference to the MongoDB database to be accessed to provide access to the various entities of the data model. Here is an example configuration:

const entityManager = new EntityManager({
  mongo: {
    default: db,
  },
})

And finally a complete example:

import { MongoClient } from "mongodb";

const uri = "mongodb+srv://sample-hostname:27017/?maxPoolSize=20&w=majority";
const client = new MongoClient(uri);

async function run() {
  try {
    await client.connect();
    const db = await client.db("dbname")
    const entityManager = new EntityManager({
      mongo: {
        default: db,
      },
    })

    // ...
    // const users = entityManager.user.findAll();
    // ...

  } finally {
    await client.close();
  }
}
run().catch(console.dir);