NodeJS
Package tarballs are available on https://cdn.sheetjs.com.
https://cdn.sheetjs.com/xlsx-0.20.3/xlsx-0.20.3.tgz is the URL for version 0.20.3
Installation
Tarballs can be directly installed using a package manager:
- npm
- pnpm
- Yarn
npm rm --save xlsx
npm i --save https://cdn.sheetjs.com/xlsx-0.20.3/xlsx-0.20.3.tgz
pnpm rm xlsx
pnpm install --save https://cdn.sheetjs.com/xlsx-0.20.3/xlsx-0.20.3.tgz
yarn remove xlsx
yarn add https://cdn.sheetjs.com/xlsx-0.20.3/xlsx-0.20.3.tgz
Newer releases of Yarn may throw an error:
Usage Error: It seems you are trying to add a package using a https:... url; we now require package names to be explicitly specified.
Try running the command again with the package name prefixed: yarn add my-package@https:...
The workaround is to prepend the URL with xlsx@
:
yarn add xlsx@https://cdn.sheetjs.com/xlsx-0.20.3/xlsx-0.20.3.tgz
Watch the repo or subscribe to the RSS feed to be notified when new versions are released!
Snyk security tooling may report errors involving "Prototype Pollution":
Prototype Pollution [Medium Severity][https://security.snyk.io/vuln/SNYK-JS-XLSX-5457926]
As noted in the Snyk report:
The issue is resolved in version 0.19.3
Snyk is falsely reporting vulnerabilities. It is a bug in the Snyk tooling.
Until Snyk fixes the bugs, the official recommendation is to suppress the warning.
Legacy Endpoints
Older releases are technically available on the public npm registry as xlsx
,
but the registry is out of date. The latest version on that registry is 0.18.5
This is a known registry bug
The SheetJS CDN https://cdn.sheetjs.com/ is the authoritative source for SheetJS modules.
For existing projects, the easiest approach is to uninstall and reinstall:
- npm
- pnpm
- Yarn
npm rm --save xlsx
npm i --save https://cdn.sheetjs.com/xlsx-0.20.3/xlsx-0.20.3.tgz
pnpm rm xlsx
pnpm install --save https://cdn.sheetjs.com/xlsx-0.20.3/xlsx-0.20.3.tgz
yarn remove xlsx
yarn add https://cdn.sheetjs.com/xlsx-0.20.3/xlsx-0.20.3.tgz
When the xlsx
library is a dependency of a dependency, the overrides
field
in package.json
can control module resolution:
{
"overrides": {
"xlsx": "https://cdn.sheetjs.com/xlsx-0.20.3/xlsx-0.20.3.tgz"
}
}
Vendoring
For general stability, making a local copy of SheetJS modules ("vendoring") is strongly recommended. Vendoring decouples projects from SheetJS infrastructure.
- Remove any existing dependency on a project named
xlsx
:
- npm
- pnpm
- Yarn
npm rm --save xlsx
pnpm rm xlsx
yarn remove xlsx
Download the tarball (
xlsx-0.20.3.tgz
) for the desired version. The current version is available at https://cdn.sheetjs.com/xlsx-0.20.3/xlsx-0.20.3.tgz
curl -o https://cdn.sheetjs.com/xlsx-0.20.3/xlsx-0.20.3.tgz
- Create a
vendor
subfolder at the root of your project:
mkdir -p vendor
- Move the tarball from step (1) to the
vendor
folder:
mv xlsx-0.20.3.tgz vendor
- If the project is managed with a version control system, add the tarball to
the source repository. The Git VCS supports the
add
subcommand:
git add vendor/xlsx-0.20.3.tgz
- Install the tarball using a package manager:
- npm
- pnpm
- Yarn
npm i --save file:vendor/xlsx-0.20.3.tgz
pnpm install --save file:vendor/xlsx-0.20.3.tgz
yarn add file:vendor/xlsx-0.20.3.tgz
Newer releases of Yarn may throw an error:
Usage Error: The file:vendor/xlsx-0.20.3.tgz string didn't match the required format (package-name@range). Did you perhaps forget to explicitly reference the package name?
The workaround is to prepend the URI with xlsx@
:
yarn add xlsx@file:vendor/xlsx-0.20.3.tgz
The package will be installed and accessible as xlsx
.
Usage
The package supports CommonJS require
and ESM import
module systems.
It is strongly recommended to use CommonJS in NodeJS.
CommonJS require
By default, the module supports require
and it will automatically add support
for encodings, streams and file system access:
var XLSX = require("xlsx");
ESM import
The package also ships with xlsx.mjs
, a script compatible with the ECMAScript
module system. When using the ESM build in NodeJS, some dependencies must be
loaded manually.
The original ECMAScript module specification only supported top-level imports:
import { Readable } from 'stream';
If a module is unavailable, there is no way for scripts to gracefully fail or ignore the error. This presents an insurmountable challenge for libraries.
To contrast, the SheetJS CommonJS modules gracefully handle missing dependencies
since require
failures are errors that the library can catch and handle.
Patches to the specification added two different solutions to the problem:
- "dynamic imports" will throw errors that can be handled by libraries. Dynamic imports will taint APIs that do not use Promise-based methods.
/* Readable will be undefined if stream cannot be imported */
const Readable = await (async() => {
try {
return (await import("stream"))?.Readable;
} catch(e) { /* silently ignore error */ }
})();
- "import maps" control module resolution, allowing library users to manually shunt unsupported modules.
These patches were released after browsers adopted ESM! A number of browsers and other platforms support top-level imports but do not support the patches.
For the ESM build, there were four unpalatable options:
A) Generate a module script for browsers, a module script for ViteJS, a module script for Deno, and a module script for NodeJS and BunJS.
B) Remove all optional features, including support for non-English legacy files.
C) Add all optional features, effectively making the features mandatory.
D) Introduce special methods for optional dependency injection.
The SheetJS team chose option (D). NodeJS native modules are still automatically loaded in the CommonJS build, but NodeJS ESM scripts must now load and pass the dependencies to the library using special methods.
It is strongly recommended to use CommonJS in NodeJS scripts!
Filesystem Operations
The set_fs
method accepts a fs
instance for reading and writing files using
readFile
and writeFile
:
import * as XLSX from 'xlsx';
/* load 'fs' for readFile and writeFile support */
import * as fs from 'fs';
XLSX.set_fs(fs);
Stream Operations
The set_readable
method accepts a stream.Readable
instance for use in stream
methods including XLSX.stream.to_csv
:
import * as XLSX from 'xlsx';
/* load 'stream' for stream support */
import { Readable } from 'stream';
XLSX.stream.set_readable(Readable);
Encoding Support
The set_cptable
method accepts an instance of the SheetJS codepage library for
use in legacy file format processing. The cpexcel.full.mjs
script must be
manually loaded. xlsx/dist/cpexcel.full.mjs
can be imported:
import * as XLSX from 'xlsx';
/* load the codepage support library for extended support with older formats */
import * as cpexcel from 'xlsx/dist/cpexcel.full.mjs';
XLSX.set_cptable(cpexcel);
NextJS
fs
cannot be imported from the top level in NextJS pages. This will not work:
/* it is safe to import the library from the top level */
import { readFile, utils, set_fs } from 'xlsx';
/* it is not safe to import 'fs' from the top level ! */
import * as fs from 'fs'; // this import will fail
set_fs(fs);
This is a design flaw in NextJS!
For server-side file processing, fs
should be loaded with a dynamic import
within a lifecycle function:
/* it is safe to import the library from the top level */
import { readFile, utils, set_fs } from 'xlsx';
import { join } from 'path';
import { cwd } from 'process';
export async function getServerSideProps() {
set_fs(await import("fs")); // dynamically import 'fs' in `getServerSideProps`
const wb = readFile(join(cwd(), "public", "sheetjs.xlsx"));
// ...
}
The NextJS demo includes complete examples.