Nest JS, Mongoose: Inject service into model - mongodb

Question

I'm having a problem with Nest Js and mongoose, Im trying to make a seed for my database,
And the main problem I'm having is I cannot import service from my module, into other module.
And it constantly gives me error:
Nest can't resolve dependencies of the CategoryModel (?). Please make sure that the argument at index [0] is available in the MongooseModule context.
the main thing I'm trying to do is to create seed for my categories.
Here is my Category Module:
import { Module } from '#nestjs/common';
import { CategoryController } from './category.controller';
import { CategoryService } from './category.service';
import { MongooseModule } from '#nestjs/mongoose';
import { CategorySchema } from 'src/models/category.schema';
#Module({
imports: [MongooseModule.forFeature([{ name: 'Category', schema: CategorySchema }])],
controllers: [CategoryController],
providers: [CategoryService]
})
export class CategoryModule {}
My Category service:
import { Model } from 'mongoose';
import { Injectable, Inject } from '#nestjs/common';
import { CategoryInterface } from '../interfaces/category.interface';
import { InjectModel } from '#nestjs/mongoose';
#Injectable()
export class CategoryService {
constructor(#InjectModel('Category') private categoryModel: Model<CategoryInterface>) {}
async create(category){
const createdQuestion = new this.categoryModel(category);
return createdQuestion.save();
}
async getMainCategories() {
return this.categoryModel.find( { parent: null } );
}
}
My Category Controller:
import { Controller, Post, Get, Body, HttpCode } from '#nestjs/common';
import { CategoryService } from './category.service';
#Controller('category')
export class CategoryController {
constructor(private categoryService: CategoryService) { }
#Post()
#HttpCode(204)
async createCategory(#Body() category) {
console.log('evo je kategorija ', category);
const data = await this.categoryService.create(category);
}
#Get('/main')
async getAllCategories() {
const data = await this.categoryService.getMainCategories();
return data;
}
}
My Seeder module where I'm having provider that seed database:
import { Module } from '#nestjs/common';
import { Seeder } from './seeder';
#Module({
providers: [Seeder],
})
export class SeederModule {}
and my seeder.ts
import { Injectable } from '#nestjs/common';
import { CategoryService } from 'src/category/category.service';
#Injectable()
export class Seeder {
constructor(private categoryService: CategoryService) { }
async seed() {
}
async categories() {
// const data = await this.categoryService.createMultiple(categories);
}
}
My App.module
import { Module } from '#nestjs/common';
import { MongooseModule } from '#nestjs/mongoose';
import { AppController } from './app.controller';
import { AppService } from './app.service';
import { CategoryModule } from './category/category.module';
import { QuizModule } from './quiz/quiz.module';
import { ConfigModule } from '#nestjs/config';
import config from './config/config';
#Module({
imports: [
MongooseModule.forRoot('mongodb://localhost:27017'),
ConfigModule.forRoot({ load: [config], isGlobal: true }),
CategoryModule,
QuizModule
],
controllers: [AppController],
providers: [AppService],
})
export class AppModule {}
Category Model:
import * as mongoose from 'mongoose';
export const CategorySchema = new mongoose.Schema({
name: { type:String, required:true, unique: true },
slug: { type:String, required:true, unique: true },
});
And for some reason it is not working, even If I import whole
GitHub Repository of Project: https://github.com/HunterJS-bit/react-quiz-app
CategoryModule, or CategoryService into Seeder.module ??
Note: To reproduce error try running npm run seed from
server/package.json
Thanks for the help :)

Answer 1

You need to have the CategoryModule add exports: [CategoryService] to allow for other modules to import the module and make use to the CategoryService. This is how you share providers in NestJS. The, you need to add imports: [CategoryModule] to the SeederModule to allow the providers of the SeederModule to use the exports of the CategoryModule. Then, everything should load up just fine.