(Self Q&A) HOW TO SETUP AND USE the MULTER MIDDLEWARE) for single file upload ( Expressjs/Nodejs ) - node.js

Question

Just wanted to post an answer to a beginner level question on HOW TO SETUP AND USE the MULTER MIDDLEWARE in Expressjs/Nodejs

Answer 1

Hope this saves your time
There should be two files:
1.Jade file(which shall contain the form lets assume index.jade)
2.JS file(which is located in the routes folder, and which directs to the index.jade file in the views folder)
SETUP index.jade file
//not a jade file so convert it to jade
//enctype is set to multipart/form-data --- multer requirement
<form method="post" role="form" enctype="multipart/form-data">
<div class="form-group">
<label for="upload">Email address:</label>
//name attribute to access in index.js route file
<input type="file" class="form-control" name="upload" id="upload">
</div>
<button type="submit" class="btn btn-default">Submit</button>
</form>
//very important
(a)In the Jade file the form must contain the attribute of enctype = "multipart/form-data"
(b)Input should have a name attribute which gets accessed in the index.js file
SETUP JS ROUTE FILE(index.js) not in app.js
var express = require('express')
var multer = require('multer')
var upload = multer({ dest: 'uploads/' }) //set dest to where you want to upload the file
var app = express()
// SINGLE FILE UPLOAD
app.post('/', upload.single('upload'), function (req, res, next) {
//since we are performing a single file upload req.file will be used and not req.files
// req.file would attach the file with upload fieldname ~ upload is the name attribute given in the form
//now use req.file to access the file
//for example
console.log(req.file); // this would display the file attributes in the log
})