app.js

var express = require('express'),
	path = require('path'),
	bodyParser = require('body-parser'),
	cons = require('consolidate');
	dust = require('dustjs-helpers'),
	pg = require('pg'),
	app = express();

const {Pool} = require('pg')


// DB connect string
var connectionString = "postgres://root:PriyaPostgres91@localhost/recipebookdb";

const pool = new Pool({
  connectionString: connectionString,
})

//Assign Dust Engine to .dust files
app.engine('dust',cons.dust);

//set Default Ext .dust
app.set('view engine','dust');
app.set('views',__dirname + '/views');

// Set public Folder
app.use(express.static(path.join(__dirname,'public')));

// Body Parser Middleware
app.use(bodyParser.json());
app.use(bodyParser.urlencoded({ extended: false }));

app.get('/',function(req,res){
	//PG connect
	pool.connect((err, client, release) => {
  		if (err) {
    		return console.error('Error acquiring client', err.stack)
  		}
  		client.query('SELECT * FROM recipes', (err, result) => {
    		if (err) {
      			return console.error('Error executing query', err.stack)
    		}
    		res.render('index',{recipes: result.rows});
    		release()
  		})
	})
});

app.post('/add',function(req,res){
	//PG connect
	pool.connect((err, client, release) => {
  		if (err) {
    		return console.error('Error acquiring client', err.stack)
  		}
  		client.query('INSERT INTO recipes(name, ingredients, directions) VALUES($1, $2, $3)', [req.body.name, req.body.ingredients, req.body.directions], (err, result) => {
    		if (err) {
      			return console.error('Error executing query', err.stack)
    		}
    		res.redirect('/');
    		release()
  		})
	});
});

app.delete('/delete/:id',function(req,res){
	//PG connect
	pool.connect((err, client, release) => {
  		if (err) {
    		return console.error('Error acquiring client', err.stack)
  		}
  		client.query('DELETE FROM recipes WHERE id = $1', [req.params.id], (err, result) => {
    		if (err) {
      			return console.error('Error executing query', err.stack)
    		}
    		res.sendStatus(200);
    		release()
  		})
	});
});

app.post('/edit',function(req,res){
	//PG connect
	pool.connect((err, client, release) => {
  		if (err) {
    		return console.error('Error acquiring client', err.stack)
  		}
  		client.query('UPDATE recipes SET name=$1, ingredients=$2, directions=$3 WHERE id=$4', [req.body.name, req.body.ingredients, req.body.directions, req.body.id], (err, result) => {
    		if (err) {
      			return console.error('Error executing query', err.stack)
    		}
    		res.redirect('/');
  		})
	});
});

// Server
app.listen(3000, function(){
	console.log('Server started On Port 3000');
});