Right now this package is used as a quick way to generate very large but very simple excel xlsx files. No formatting yet, no date conversions etc.

Creating an xlsx blob in browser for 150000 rows x 80 columns of different data takes around 60 seconds.

This was rewritten from coffee script https://github.com/rubenv/node-xlsx-writer and changed to work both in browser and nodejs. Api is completely different from rubenv implementation.

It is actually capable of streaming rows into xlsx file both in browser and nodejs.

It uses JSZip to compress resulting structure. Lucky for us JSZip is capable of processing readable streams, so we just stream rows into xlxs file (which is a zip file).

Plans:

• improve api
• add tests
• make browser build, put on some cdn
• optimize shared string stuff
• (maybe) use web workers to build xlsx in browser
• (maybe) implement some specifis for nodejs

You can add rows:

const XlsxStreamWriter = require("xlsx-stream-writer");
const fs = require("fs");

const rows = [
  ["Name", "Location"],
  ["Alpha", "Adams"],
  ["Bravo", "Boston"],
  ["Charlie", "Chicago"],
];

const xlsx = new XlsxStreamWriter();
xlsx.addRows(rows);

xlsx.getFile().then(buffer => {
  fs.writeFileSync("result.xlsx", buffer);
});

Or add readable stream of rows:

const XlsxStreamWriter = require("xlsx-stream-writer");
const Readable = require("stream-browserify").Readable;
const fs = require("fs");

const rows = [
  ["Name", "Location"],
  ["Alpha", "Adams"],
  ["Bravo", "Boston"],
  ["Charlie", "Chicago"],
];

function wrapRowsInStream(rows) {
  const rs = Readable({ objectMode: true });
  let c = 0;
  rs._read = function() {
    if (c === rows.length) rs.push(null);
    else rs.push(rows[c]);
    c++;
  };
  return rs;
}
const streamOfRows = wrapRowsInStream(rows);

const xlsx = new XlsxStreamWriter();
xlsx.addRows(streamOfRows);

xlsx.getFile().then(buffer => {
  fs.writeFileSync("result.xlsx", buffer);
});