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Bundling Sheets with RollupJS

RollupJS is a module bundler.

SheetJS is a JavaScript library for reading and writing data from spreadsheets.

This demo uses RollupJS and SheetJS to export data. We'll explore how to bundle SheetJS in a site using RollupJS and how to export data to spreadsheets.

This demo focuses on integration details with the RollupJS bundler.

The demos follow the "Export Tutorial", which covers SheetJS library usage in more detail.

Tested Deployments

This demo was tested in the following environments:


Integration Details

The "Frameworks" section covers installation with Yarn and other package managers.

After installing the SheetJS module in a RollupJS project, import statements can load relevant parts of the library:

import { read, utils, writeFileXLSX } from 'xlsx';

Required Plugin

RollupJS can support NodeJS modules using the @rollup/plugin-node-resolve plugin. The flag --plugin @rollup/plugin-node-resolve should be passed to the RollupJS CLI tool

npx rollup index.js --plugin @rollup/plugin-node-resolve --file bundle.js --format iife

Complete Example

0) Initialize a new project:

mkdir sheetjs-rollup
cd sheetjs-rollup
npm init -y

1) Install the tarball using a package manager:

yarn add [email protected] @rollup/plugin-node-resolve

2) Save the following to index.js:

import { utils, version, writeFileXLSX } from 'xlsx';

document.getElementById("xport").addEventListener("click", async() => {
/* fetch JSON data and parse */
const url = "";
const raw_data = await (await fetch(url)).json();

/* filter for the Presidents */
const prez = raw_data.filter(row => row.terms.some(term => term.type === "prez"));

/* sort by first presidential term */
prez.forEach(row => row.start = row.terms.find(term => term.type === "prez").start);
prez.sort((l,r) => l.start.localeCompare(r.start));

/* flatten objects */
const rows = => ({
name: + " " +,

/* generate worksheet and workbook */
const worksheet = utils.json_to_sheet(rows);
const workbook = utils.book_new();
utils.book_append_sheet(workbook, worksheet, "Dates");

/* fix headers */
utils.sheet_add_aoa(worksheet, [["Name", "Birthday"]], { origin: "A1" });

/* calculate column width */
const max_width = rows.reduce((w, r) => Math.max(w,, 10);
worksheet["!cols"] = [ { wch: max_width } ];

/* create an XLSX file and try to save to Presidents.xlsx */
writeFileXLSX(workbook, "Presidents.xlsx");

3) Bundle the script:

npx rollup index.js --plugin @rollup/plugin-node-resolve --file bundle.js --format iife

This step will create bundle.js

4) Create a small HTML page that loads the script. Save to index.html:

<!DOCTYPE html>
<html lang="en">
<h1>SheetJS Presidents Demo</h1>
<button id="xport">Click here to export</button>
<script type="module" src="./bundle.js"></script>

5) Start a local HTTP server:

npx http-server .

Access the displayed URL (typically http://localhost:8080/) in a web browser. Click on "Click here to export" to generate a file.