---
title: Bundling Sheets with RollupJS
sidebar_label: RollupJS
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---
import current from '/version.js';
import Tabs from '@theme/Tabs';
import TabItem from '@theme/TabItem';
import CodeBlock from '@theme/CodeBlock';
[RollupJS](https://rollupjs.org/) is a module bundler.
[SheetJS](https://sheetjs.com) 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.
:::note
This demo was last tested on 2023 October 21 against RollupJS 4.1.4
:::
## Integration Details
[The "Frameworks" section](/docs/getting-started/installation/frameworks) 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:
```js
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
```bash
npx rollup index.js --plugin @rollup/plugin-node-resolve --file bundle.js --format iife
```
## Complete Example
0) Initialize a new project:
```bash
mkdir sheetjs-rollup
cd sheetjs-rollup
npm init -y
```
1) Install the tarball using a package manager:
{`\
npm i --save https://cdn.sheetjs.com/xlsx-${current}/xlsx-${current}.tgz`} rollup@4.1.4 @rollup/plugin-node-resolve
{`\
pnpm install https://cdn.sheetjs.com/xlsx-${current}/xlsx-${current}.tgz`} rollup@4.1.4 @rollup/plugin-node-resolve
{`\
yarn add https://cdn.sheetjs.com/xlsx-${current}/xlsx-${current}.tgz`} rollup@4.1.4 @rollup/plugin-node-resolve
2) Save the following to `index.js`:
```js title="index.js"
// highlight-next-line
import { utils, version, writeFileXLSX } from 'xlsx';
document.getElementById("xport").addEventListener("click", async() => {
/* fetch JSON data and parse */
const url = "https://sheetjs.com/data/executive.json";
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"));
/* flatten objects */
const rows = prez.map(row => ({
name: row.name.first + " " + row.name.last,
birthday: row.bio.birthday
}));
/* 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, r.name.length), 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:
```bash
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`:
```html title="index.html"
SheetJS Presidents Demo
```
5) Start a local HTTP server:
```bash
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.