Create-backend-project NPM

Package: Create-backend-project

Description: Creates entire express backend project with all the necessary files and folders that follows industry standard template.

Usage:

npx create-backend-app

cd <project_name>
npm install

write your database name in the database/index.js
const DBName = ""; //replace your database name
Add your mongoDB connection string, password and CORS origin in the .env file
  MONGO_URI=mongodb+srv://USERNAME:<db_password>@cluster-test.dyzrsx0.mongodb.net/
  MONGO_PASS=abcde12345
  CORS_ORIGIN=http://localhost:3000

Folder structure:

project-name
├── src
│   ├── app.js
│   ├── server.js
│   ├── constants.js
│   ├── models
│   ├── routes
│   ├── utils
│   │   ├── catchAsyncError.js
│   │   └── appError.js
│   ├── cors
│   │   └── index.js
│   ├── database
│   │   └── index.js
│   ├── middlewares
│   │   └── error.middleware.js
│   └── controllers
│       └── error.controller.js
├── .gitignore
├── .env
└── package.json

Comoponents

Error handling middleware

const handleError = (err, req, res, next) => {
  err.statusCode = err.statusCode || 500;
  err.status = err.status || `error`;
  if (process.env.NODE_ENV === `development`) {
    return sendDevelopmentError(err, res);
  }
  let error = { ...err };
  error.message = err.message;
  // console.log(error);
  // console.log(err.message);
  if (err.code === 11000) error = duplicationError(error);
  return sendProductionError(error, res);
};

Usage:
This middleware will be used to handle all the errors in the application. It will send a detailed error message in the development environment and will send a user-friendly message in the production environment.

CatchAsyncError

const catchAsyncError = (cb) => {
  return (req, res, next) => {
    cb(req, res, next).catch((error) => {
      next(error);
    });
  };
};
export default catchAsyncError;

Usage:

No need to write try-catch block in the controller function.
Wrap all your controller function with this catchAsyncError(controller_function) function to handle all the errors in the application.
Import the class AppError from #utils/appError.js and Just throw new AppError(message, statusCode) the error will be handled automatically by the AppError class.
Example:

import catchAsyncError from '#utils/catchAsyncError.js';
import AppError from '#utils/appError.js';

export const getOne = catchAsyncError(async (req, res, next) => {
  const user = await User.findById(req.params.id);
    if (!user) {
        throw new AppError(`No user found with that ID`, 404);
    }
    res.status(200).json({
        status: `success`,
        data: {
            user
        }
    });
});

MongoDb Connection

import mongoose from "mongoose";

const DBName = ""; //replace your database name

const connectDB = async () => {
  const DBUrl = process.env.MONGO_URI.replace(
    `<db_password>`, //make sure names in env are correct and the password part in the uri is same like this
    process.env.MONGO_PASS
  );
  const response = await mongoose.connect(`${DBUrl}/${DBName}`);
};
export default connectDB;

Usage:
1. Replace the DBName with your database name.
2. In .env file add the mongoDB connection string into the MONGO_URI.
3. In .env file add your mongoDb into the MONGO_PASS.
Example:
```
MONGO_URI=mongodb+srv://USERNAME:<db_password>@cluster-test.dyzrsx0.mongodb.net/
MONGO_PASS=abcde12345
```

CORS

import cors from "cors";

const corsOptions = {
  origin: process.env.CORS_ORIGIN || "http://localhost:8003",
  optionsSuccessStatus: 200,
  credentials: true,
};

export default cors(corsOptions);