My productController.js

const Product = require('../models/product');



const ErrorHandler = require('../utils/errorHandler');

const catchAsyncError = require('../middlewares/catchAsyncErrors');

const APIFeatures = require('../utils/apiFeatures');



// Get all products => /api/v1/products

exports.getProducts = catchAsyncError(async (req, res, next) => {



    const resPerPage = 4;

    const productCount = await Product.countDocuments();



    const apiFeatures = new APIFeatures(Product.find(), req.query)

                        .search()

                        .filter()

                        .pagination(resPerPage)

    const products = await apiFeatures.query;



    res.status(200).json({

        success: true,

        count: products.length,

        message: 'All products fetched from the database successfully.',

        productCount,

        products

    })

}

)

My APIFeatures.js

const { remove } = require("../models/product");



class APIFeatures {

    constructor(query, queryStr) {

        this.query = query;

        this.queryStr = queryStr;

    }



    search() {

        const keyword = this.queryStr.keyword ? {

            name: {

                $regex: this.queryStr.keyword,

                $options: 'i' // Case insensitive option

            }

        } : {}



        this.query = this.query.find({ ...keyword })

        return this;

    }



    filter() {

        const queryCopy = { ...this.queryStr };



        // Remove the fields from the query string

        const removeFields = ['keyword', 'limit', 'page']

        removeFields.forEach(el => delete queryCopy[el]);



        // Advanced filtering

        let queryStr = JSON.stringify(queryCopy);

        queryStr = queryStr.replace(/b(gt|gte|lt|lte|in)b/g, match => `$${match}`);



        this.query = this.query.find(JSON.parse(queryStr));

        return this;

    }



    pagination(resPerPage) {

        const currentPage = Number(this.queryStr.page) || 1;

        const skip = resPerPage * (currentPage - 1);



        this.query = this.query.limit(resPerPage).skip(skip)

    }

}



module.exports = APIFeatures; 

There's a problem with getting all products. Getting single product works fine so I removed that part of the code. The problem is with the query.

I have 2 sample product in my database and it was working fine. I didn't make changes this file but I can't fetch all products using postman.

  const products = await apiFeatures.query;