What is the proper way to do seed mongoDB in NestJS, using mongoose and taking advantage of my already defined schmas

I've done using the nestjs-command library like that.

1. Install the library:

https://www.npmjs.com/package/nestjs-command

2. Then I've created a command to seed my userService like:

src/modules/user/seeds/user.seed.ts

import { Command, Positional } from 'nestjs-command';import { Injectable } from '@nestjs/common';import { UserService } from '../../../shared/services/user.service';@Injectable()export class UserSeed {constructor(    private readonly userService: UserService,) { }@Command({ command: 'create:user', describe: 'create a user', autoExit: true })async create() {    const user = await this.userService.create({        firstName: 'First name',        lastName: 'Last name',        mobile: 999999999,        email: 'test@test.com',        password: 'foo_b@r',    });    console.log(user);}}

3. Add that seed command into your module. I've created a SeedsModule in a shared folder to add more seeds in future

src/shared/seeds.module.ts

import { Module } from '@nestjs/common';import { CommandModule } from 'nestjs-command';import { UserSeed } from '../modules/user/seeds/user.seed';import { SharedModule } from './shared.module';@Module({    imports: [CommandModule, SharedModule],    providers: [UserSeed],    exports: [UserSeed],})export class SeedsModule {}

Btw I'm importing my userService into my SharedModule

4. Add the SeedsModule into your AppModule

On your AppModule usually at src/app.module.ts add the SeedsModule into imports

Final

If you followed the steps in the nestjs-command repo you should be able to run

npx nestjs-command create:user

That will bootstrap a new application and run that command and then seed to your mongo/mongoose

Hope that help others too.