How to upload an image in NodeJS?

Good afternoon,

I want to make a POST request from the client in JAVASCRIPT with DATA Send (file .jpg) in date URL for server in NODEJS.

[Client] - JavaScript 

    finalImg.onload = function(event){
        var request = new XMLHttpRequest();
        request.onload = function (event) {
            if (request.readyState == 4 && request.status == 200) {
                console.log(request.responseText);
            }
        };

        request.open('post', '/setimageprofile', true);
        request.setRequestHeader('Content-type', 'image/JPEG;charset=UTF-8');
        request.send(finalImg);
    }

[Server] - NodeJs 

app.post('/setimageprofile', function(req, res) {
    //var request_data = '';
    var writable = fs.createWriteStream('./client_imgs/getusername.jpg');
    req.on('data', function(data){
        writable.write(data);
    });

    req.on('end', function() {
        writable.end();
    });
});

[problem] When I open file ./ client_imgs / getusername.jpg with the image viewer I have the error "we do not support this file format". Apparently I should make a cast of the date that it's being sent to me, Am I right? If so, how to do?

[Note] On the server I have, 

const bodyParser = require("body-parser");
var express = require('express');
var fs = require('fs');
var url = require('url');
var app = express();

app.use(bodyParser.urlencoded({
    extended: true
}));
app.use(bodyParser.json());
Author: Pedro Correia, 2019-02-20
Source

1 answers

[UPDATE] found solution

[server] 

app.post('/setimageprofile', function(req, res) {
    var request_data = '';
    var writable = fs.createWriteStream('./client_imgs/getusername.png', 'base64');
    req.on('data', function(data){
        request_data += data;
    });

    req.on('end', function() {
        request_data = JSON.parse(request_data).data;
        var base64Data = request_data.replace(/^data:image\/png;base64,/, "");
        console.log(base64Data);
        writable.write(base64Data);

        writable.end();
    });
});

[client] 

var data = { data : finalImgURL};
        console.log('type: ' + dataTypeFromParent);
        // post - send image to server
        finalImg.onload = function(event){
            var request = new XMLHttpRequest();
            request.onload = function (event) {
                if (request.readyState == 4 && request.status == 200) {
                    console.log(request.responseText);
                }
            };

            request.open('post', '/setimageprofile', true);
            request.setRequestHeader('Content-type', 'plain/text;charset=UTF-8');
            request.send(JSON.stringify(data));
        }
 2
Author: Pedro Correia, 2019-02-20 17:09:12