how to connect mongodb using koa js through mongoose

Question

I have already done connect MongoDB using mongodbClient. but I want to connect MongoDB through mongoose.

This is my current configuration

this is Db Connection import { MongoClient } from 'mongodb';

const URI = 'xxxxxxxxxxxxxxxxxxxxx';

const mongoClient = new MongoClient(URI);

mongoClient.connect().then(() => {
    console.log("Db connected");
});

export default mongoClient;

Server configuration start here it will use to call middleware

import Koa from 'koa';
import bodyParser from 'koa-bodyparser';
import postRouter from './postRouter.js';
import './db/mongoClient.js'
const app = new Koa();



app.use(bodyParser());
app.use(postRouter.routes())
    .use(postRouter.allowedMethods());


app.use(ctx => {
    ctx.response.set('Access-Control-Allow-Origin', 'http://localhost:1234');
    ctx.response.set('Access-Control-Allow-Origin', 'GET, POST, OPTIONS, PUT, DELETE');
    ctx.response.set('Access-Control-Allow-Origin', '*');
    next();
});

app.use((ctx) => {
    ctx.body = 'Resource you are looking for was not found';
    ctx.status = 404;
})




app.listen(3000);

console.log("App is running on port 3000");

Controller configuration starts here,

import { ObjectId } from "mongodb";
import mongoClient from "./db/mongoClient.js";

const collection = mongoClient.db('posts').collection('post');

const save = async (post) => {
    const inserted = await collection.insertOne({ ...post });
    return inserted.insertedId;
};

const getAll = async () => {
    const cursor = await collection.find();
    const posts = [];
    await cursor.forEach(doc => {
        const { _id: id, title, description, user, posted } = doc;
        posts.push({ id, title, description, user, posted });
    });


    return posts;


};

const getByDataId = async (findId) => {
    const doc = await collection.findOne({ _id: ObjectId(findId) });
    const { _id: id, title, description, user, posted } = doc;
    return { id, title, description, user, posted };

};

export { save, getAll, getByDataId };

Answer 1

CourseModels

const mongoose = require('mongoose');



const CourseScheema = new mongoose.Schema({



   courseName:
    {
        type: String,
        require: true,
    },



   coursefee:
    {
        type: Number,
        require: true,
    },



   student:
        [{
            type: mongoose.Schema.Types.ObjectId,
            require: false,
            ref: "students"
        }],





});



const Course = mongoose.model("course", CourseScheema);



module.exports = Course;

Router-course

const KoaRouter = require('koa-router');
const { addCourse, getcourse, updatecourse, deleteCourse } = require('../controller/courseController');
const router = new KoaRouter({ prefix: "/course" })



router.post("/add", addCourse);
router.put("/:courseId", updatecourse);
router.delete("/:courseId", deleteCourse);
router.get("/", getcourse);





module.exports = router;

Controller- course

const Course = require("../models/courseModel");




const addCourse = async (ctx) => {



   try {
        const { courseName, coursefee, student } = ctx.request.body;




        const course = await Course.create({



           courseName: courseName,
            coursefee: coursefee,
            student: student,
        });



       return (ctx.body = { course: course });
    } catch {



       return (ctx.body = { message: error.message });
    }
}




//get function



const getcourse = async (ctx) => {



   try {
        const courses = await Course.find({});



       return (ctx.body = { courses: courses })
    } catch (error) {
        return (ctx.body = { message: error.message })
    }
}



//update
const updatecourse = async (ctx) => {



   try {
        const courseId = ctx.params.courseId;



       const { courseName, coursefee, student } = ctx.request.body;
        const course = await Course.findByIdAndUpdate(courseId, {
            courseName: courseName,
            coursefee: coursefee,
            student: student
        });
        return (ctx.body = course);
    } catch (error) {
        return (ctx.body = { message: error.message })
    }
};



//delete function



const deleteCourse = async (ctx) => {



   try {
        const courseId = ctx.params.courseId;
        const course = await Course.findByIdAndDelete(courseId);
        return (ctx.body = course);



   } catch (error) {
        return (ctx.body = { message: error.message })
    }
}



module.exports = {
    addCourse,
    getcourse,
    updatecourse,
    deleteCourse,
}

Package.json

{
  "name": "backend",
  "version": "1.0.0",
  "description": "",
  "main": "index.js",
  "scripts": {
    "dev" : "nodemon index.js",
    "start": "node index.js"
  },
  "author": "shanu",
  "license": "ISC",
  "dependencies": {
    "@koa/cors": "^3.3.0",
    "dotenv": "^16.0.1",
    "koa": "^2.13.4",
    "koa-bodyparser": "^4.3.0",
    "koa-json": "^2.0.2",
    "koa-router": "^10.1.1",
    "mongoose": "^6.4.0"
  },
  "devDependencies": {
    "nodemon": "^2.0.18"
  }
}