how to save byte array as zip in angular - arrays

Question

I'm trying to download (using FileSaver.saveAs) a byte array getting from the server (nodejs\express) as a zip. I'm manage to download it as zip, but it doesn't open (it is invalid).
I had few miss-clarities regarding the way the data should be defined - content type, responseType both in the server and in the client, should I convert it to a blob, etc) - but I think I over-come them with the detailed below code.
The problem is at the final function, in the exportAsZip function - the data reaches there in the right size, but converting it to a Blob inflate it and probably corrupt it.
Here is my code (server side - node.js-express using middleware function):
THIS IS ALREADY UPDATED AS FIXED CODE:
The router is express-router:
router.use(<some route>,(req, res, next) => {
return getData(req.query).then((dataResult) =>
{
{
res.contentType('application/zip');
return res.send([dataResult]); //Data result is byte array
}).catch((err) => {
console.error(err);
});
});
In the client side (angular):
This is the component function:
downloadAsZip()
{
let fileName : string = <fileName>;
this.srv.getData().subscribe(result =>
{
// const blob = new Blob([result], { type: 'application/octet-stream' })
/*This is the needed fix:*/
const byteArray = new Uint8Array(result);
const blob = new Blob([byteArray]);
this.fileService.exportAsZip(blob, fileName);
},
error => console.log(error)
);
}
This is the srv.getData code:
getData() : Observable<any>
{
return this.http.get(<path>, /*{ responseType: 'blob' } - not needed*/)
}
This is the fileService function (exportAsZip):
exportAsZip(data, fileName)
{
/*The data is with a correct size, but converting it to a blob object inflate its size*/
/*this should be removed also*/
//const blobData: Blob = new Blob([data], {type: 'application/zip'});
FileSaver.saveAs(/*blobD*/data, fileName + '.zip');
}

Answer 1

Fixed the problem - The main change is to convert the byte Array data to Uint8Array and then create a blob which will be saved using the FileSaver.saveAs.
Also, removed the { responseType: 'blob' } from the get request header.
The above code is now fixed !