docs.sheetjs.com/docz/docs/04-getting-started/03-demos/09-bundler.md

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9	Bundlers

import current from '/version.js'; import Tabs from '@theme/Tabs'; import TabItem from '@theme/TabItem';

SheetJS predates ECMAScript modules and bundler tools like Webpack. As best practices have evolved, stress testing SheetJS libraries have revealed bugs in the respective bundlers. This demo collects various notes and provides basic examples.

:::note

Issues should be reported to the respective bundler projects. Typically it is considered a bundler bug if the tool cannot properly handle JS libraries.

:::

Browserify

browserify is compatible with the library and should "just work" with the require form in a main page or in a web worker:

var XLSX = require("xlsx");
// ... use XLSX ...

After installing the module, bundling is easy:

browserify app.js > browserify.js
uglifyjs browserify.js > browserify.min.js

Web Worker scripts can be bundled using the same approach.

Complete Example (click to show)

1. Install the tarball using a package manager:

{`\
$ npm install --save https://cdn.sheetjs.com/xlsx-${current}/xlsx-${current}.tgz`}

{`\
$ pnpm install --save https://cdn.sheetjs.com/xlsx-${current}/xlsx-${current}.tgz`}

{`\
$ yarn add --save https://cdn.sheetjs.com/xlsx-${current}/xlsx-${current}.tgz`}

2. Download the following files:

• app.js
• index.html
• xlsxworker.js

3. Bundle the scripts:

npx browserify app.js > browserify.js
npx browserify xlsxworker.js > worker.js

4. Spin up a local web server:

npx http-server 

5. Access the site http://localhost:8080/ and use the file input element to select a spreadsheet.

Bun

bun bun is capable of optimizing imported libraries in node_modules. In local testing, a bundled script can save tens of milliseconds per run.

Complete Example (click to show)

1. Install the tarball using a package manager:

{`\
$ npm install --save https://cdn.sheetjs.com/xlsx-${current}/xlsx-${current}.tgz`}

{`\
$ pnpm install --save https://cdn.sheetjs.com/xlsx-${current}/xlsx-${current}.tgz`}

{`\
$ yarn add --save https://cdn.sheetjs.com/xlsx-${current}/xlsx-${current}.tgz`}

2. Save the following script to bun.js:

// highlight-next-line
import * as XLSX from 'xlsx/xlsx.mjs';
// highlight-next-line
import * as fs from 'fs';
// highlight-next-line
XLSX.set_fs(fs);

/* fetch JSON data and parse */
const url = "https://sheetjs.com/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 = XLSX.utils.json_to_sheet(rows);
const workbook = XLSX.utils.book_new();
XLSX.utils.book_append_sheet(workbook, worksheet, "Dates");

/* fix headers */
XLSX.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 */
XLSX.writeFile(workbook, "Presidents.xlsx");

3. Bundle the script with bun bun:

bun bun bun.js

This procedure will generate node_modules.bun.

4. Run the script

bun bun.js

ESBuild

The xlsx.mjs source file are written in a subset of ES6 that ESBuild understands and is able to transpile down for older browsers.

Both the node and browser platforms work out of the box.

Complete Example (click to show)

1. Install the tarball using a package manager:

{`\
$ npm install --save https://cdn.sheetjs.com/xlsx-${current}/xlsx-${current}.tgz`}

{`\
$ pnpm install --save https://cdn.sheetjs.com/xlsx-${current}/xlsx-${current}.tgz`}

{`\
$ yarn add --save https://cdn.sheetjs.com/xlsx-${current}/xlsx-${current}.tgz`}

2. Save the following to esbrowser.js:

// highlight-next-line
import { set_fs, utils, version, writeFile } from 'xlsx/xlsx.mjs';

(async() => {
/* fetch JSON data and parse */
const url = "https://sheetjs.com/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 */
writeFile(workbook, "Presidents.xlsx");
})();

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

<body><script src="esb.browser.js"></script></body>

4. Create bundle:

npx esbuild esbrowser.js --bundle --outfile=esb.browser.js

5. Start a local HTTP server, then go to http://localhost:8080/

npx http-server .

1. Install the tarball using a package manager:

{`\
$ npm install --save https://cdn.sheetjs.com/xlsx-${current}/xlsx-${current}.tgz`}

{`\
$ pnpm install --save https://cdn.sheetjs.com/xlsx-${current}/xlsx-${current}.tgz`}

{`\
$ yarn add --save https://cdn.sheetjs.com/xlsx-${current}/xlsx-${current}.tgz`}

2. Save the following to esbnode.js:

// highlight-next-line
import { set_fs, utils, version, writeFile } from 'xlsx/xlsx.mjs';
// highlight-next-line
import * as fs from 'fs';
// highlight-next-line
set_fs(fs);

(async() => {
/* fetch JSON data and parse */
const url = "https://sheetjs.com/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 */
writeFile(workbook, "Presidents.xlsx");
})();

3. Create bundle:

npx esbuild esbnode.js --bundle --platform=node --outfile=esb.node.js

4. Run the bundle:

node esb.node.js

Parcel

Parcel Bundler should play nice with SheetJS out of the box.

:::warning Parcel Bug

Errors of the form Could not statically evaluate fs call stem from a parcel bug. Upgrade to Parcel version 1.5.0 or later.

:::

Complete Example (click to show)

This demo follows the Presidents Example.

1. Save the following to index.html:

<body>
<h3>SheetJS <span id="vers"></span> export demo</h3>
<button id="xport">Click to Export!</button>
<!-- the script tag must be marked as `type="module"` -->
<!-- highlight-next-line -->
<script type="module">
// ESM-style import from "xlsx"
// highlight-next-line
import { utils, version, writeFile } from 'xlsx';

document.getElementById("vers").innerText = version;
document.getElementById("xport").onclick = async() => {
  /* fetch JSON data and parse */
  const url = "https://sheetjs.com/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 */
  writeFile(workbook, "Presidents.xlsx");
};
</script>
<body>

2. Install the SheetJS node module:

{`\
$ npm install --save https://cdn.sheetjs.com/xlsx-${current}/xlsx-${current}.tgz`}

{`\
$ pnpm install --save https://cdn.sheetjs.com/xlsx-${current}/xlsx-${current}.tgz`}

{`\
$ yarn add --save https://cdn.sheetjs.com/xlsx-${current}/xlsx-${current}.tgz`}

3. Run the Parcel CLI tool:

npx -y parcel index.html

4. Access the page listed in the output (typically http://localhost:1234) and click the "Click to Export!" button to generate a file.