XSD file always corrupt when uploaded to server

Hello, sorry if this duplicate.
So my server code always gave me the corrupt xsd file.
So here is my server code.

``` javascript
var myCustomStorage = require('./custom-storage');
var storage = myCustomStorage({
destination: function (req, file, cb) {
cb(null, './files/' + Date.now() + file.originalname)
}
});

var cpUpload = multer({ storage: storage, limits: {fieldSize: 10000000, fieldNameSize: 10000000}}).single('schema-file');

var app = express();
app.use(function(req, res, next) {
res.header("Access-Control-Allow-Origin", "*");
res.header("Access-Control-Allow-Headers", "Origin, X-Requested-With, Content-Type, Accept");
res.header('Access-Control-Allow-Methods', 'GET,PUT,POST,DELETE,PATCH,OPTIONS');
next();
});
app.use(cpUpload);
app.use(timeout(200000));
app.use(haltOnTimedout);

function haltOnTimedout(req, res, next){
if (!req.timedout){
next();
}else{
res.set('Content-Type', 'application/json');
res.end(JSON.stringify({
status: 'SUCCESS 1',
description: 'success'
}));
}
}

app.post('/ws-api-designer-upload-files', cpUpload, function (req, res, next) {
cpUpload(req,res,function(err){
if(err){
res.set('Content-Type', 'application/json');
res.end(JSON.stringify({
status: 'ERROR 1',
description: err.message
}));
return;
}else{
res.set('Content-Type', 'application/json');
res.end(JSON.stringify({
status: 'SUCCESS 1',
description: 'success'
}));
return;
}
});
});
```
front-end code
``` javascript
postFile(fileToUpload: File)/*: Observable*/ {
const endpoint = 'http://localhost:3000/ws-api-designer-upload-files';
const file: FormData = new FormData();
file.append('schema-file', fileToUpload, fileToUpload.name);
let headers = new HttpHeaders();
headers.append('Content-Type', 'application/x-www-form-urlencoded');

return new Promise((resolve, reject) => {
this.http.
post(endpoint, file, { headers: headers })
.subscribe(res => {
resolve(res);
}, (err) => {
reject(err);
});
});
}
```

When i execute by uploading the xsd file it says success. But when i compare the [original file ](https://i.stack.imgur.com/GfGg0.png)and [uploaded file](https://i.stack.imgur.com/URapv.png) are not the same.
[This is the original file](https://pastebin.com/RsEeY5fJ)
[This is the uploaded file](https://pastebin.com/2xfe5yds)
Any help would be appreciated!