Sheetjs: Add support for streaming to xlsx or xlsb

[msahil432]

First of all, thanks for the library.

Second, I need support for streaming files to xlsx or xlsb
Currently there is the support for streaming files as csv, json and html, is there a workaround to do the same for xls?
I mean there is an option to save files as xlsx directly, so may be same can be used here?!

Thanks again.

[msahil432]

Well, I found the functionality within the library, at least for my specific case.

I needed to pipe/stream xlsx object as blob or buffer to a client from my express server. And here is the code which I ended up using, as it turns out library provides in built support for buffer and expressJS can send a buffer successfully to the client.

response.setHeader('Content-Type', 'application/octet-stream');
response.setHeader('Content-Disposition', 'attachment; filename="File.xlsx"');

let data = JSON.parse(request.body.data);
var wb = XLSX.utils.book_new();
var ws = XLSX.utils.json_to_sheet(data);
XLSX.utils.book_append_sheet(wb, ws, "Sheet1");
var wbopts = {
type: 'buffer',
bookType: "xlsx",
bookSST: false
};
var wbout = XLSX.write(wb, wbopts);
response.send(wbout);

In above code, I am writing a file to storage, Converting JSON to XLSX inside code, and client can save the result to file.

As for CSV, here is the code if again, someone wants it:

response.setHeader('Content-Type', 'application/octet-stream');
response.setHeader('Content-Disposition', 'attachment; filename="File.csv"');
....
XLSX.utils.book_append_sheet(workbook, worksheet, 'Sheet1');

var stream = XLSX.stream.to_csv(ws);
stream.pipe(response);

Thanks @SheetJSDev again, for this great library.

[jedwards1211]

It's extremely strange that there aren't streaming functions for all supported output formats