Adding a custom provider for MongoDB [v6]

[usersina]

No mongoose or anything, I just want to add a simple MongoDB provider and I actually managed to do it.

However, I get typescript errors and it's not type-safe.

// adonisrc.ts

...
  providers: [
    ...
    () => import('#providers/mongo_provider'),
  ],
...

// providers/mongo_provider.ts

import type { ApplicationService } from '@adonisjs/core/types'
import { MongoClient } from 'mongodb'

import env from '#start/env'

export default class MongoProvider {
  constructor(protected app: ApplicationService) {}

  /**
   * Register bindings to the container
   */
  register() {
    this.app.container.singleton('mongo', () => { // <-- typescript error "No overload matches this call."
      return new MongoClient(env.get('MONGO_URI'))
    })
  }

  /**
   * The container bindings have booted
   */
  async boot() {
    const mongoClient = await this.app.container.make('mongo') // <-- `mongoClient` is not typesafe
    await mongoClient.connect()
  }

  /**
   * The application has been booted
   */
  async start() {
    const mongoClient = await this.app.container.make('mongo') // <-- `mongoClient` is not typesafe
    await mongoClient.db('admin').command({ ping: 1 })
  }

  /**
   * The process has been started
   */
  async ready() {}

  /**
   * Preparing to shutdown the app
   */
  async shutdown() {
    const mongoClient = await this.app.container.make('mongo') // <-- `mongoClient` is not typesafe
    await mongoClient.close()
  }
}

Needless to say, npm run typecheck fails. Here's the typescript error:

Argument of type String is not assignable to parameter of type AbstractConstructor<any>

No overload matches this call.
Overload 1 of 2, '(binding: keyof ContainerBindings, resolver: BindingResolver<ContainerBindings, ApplicationService | Kernel | Dumper | ... 8 more ... | Repl>): void', gave the following error.
Argument of type '"mongo"' is not assignable to parameter of type 'keyof ContainerBindings'.
Overload 2 of 2, '(binding: AbstractConstructor, resolver: BindingResolver<ContainerBindings, any>): void', gave the following error.
Argument of type 'string' is not assignable to parameter of type 'AbstractConstructor'.

[usersina]

I figured it out reading through the Dependency injection (DI) -> Defining static types for bindings section in the documentation.

// app/types/container.ts

import { MongoClient } from 'mongodb'

declare module '@adonisjs/core/types' {
  interface ContainerBindings {
    mongo: MongoClient
  }
}