index.js

const express = require('express');
const bodyParser = require('body-parser');
const mongoose = require('mongoose');
const multer = require('multer');
const path = require('path');

const app = express();
const authRoutes = require('./src/routes/auth')
const blogRouters = require('./src/routes/blog')

const fileStorage = multer.diskStorage({
    destination: (req, file, cb) => {
        cb(null, 'images');
    },
    filename: (req, file, cb) => {
        cb(null, new Date().getTime() + '-' + file.originalname)
    }
})

const fileFilter = (req, file, cb) => {
    if( 
        file.mimetype === 'image/png' || 
        file.mimetype === 'image/jpg' || 
        file.mimetype === 'image/jpeg'
    ){
        cb(null, true);
    } else {
        cb(null, false);
    }
}

app.use(bodyParser.json())
app.use('/images', express.static(path.join(__dirname, 'images')))
app.use(multer({storage: fileStorage, fileFilter: fileFilter}).single('image'));

app.use((req, res, next) => {
    res.setHeader('Access-Control-Allow-Origin', '*');
    res.setHeader('Access-control-Allow-Methods', 'GET, POST, PUT, PATCH, DELETE, OPTIONS');
    res.setHeader('Acces-Control-Allow-Headers', 'Content-Type, Authorization');
    next();
})


app.use('/v1/', authRoutes);
app.use('/v1/blog', blogRouters)

app.use((error, req, res, next) => {
    const status = error.errorStatus || 500;
    const message = error.message;
    const data = error.data;

    res.status(status).json({mesage: message, data: data})
});

    mongoose.connect('mongodb://giw:1234@ac-b71ykod-shard-00-00.jgl16sn.mongodb.net:27017,ac-b71ykod-shard-00-01.jgl16sn.mongodb.net:27017,ac-b71ykod-shard-00-02.jgl16sn.mongodb.net:27017/blog?ssl=true&replicaSet=atlas-11fm9u-shard-0&authSource=admin&retryWrites=true&w=majority')
    .then(() => {
        app.listen(4000, () => console.log('Connection Success'));
    })
    .catch(err => console.log(err));