express-cors

library0.0.3jsnpmunverified

A lightweight middleware for Express.js (versions 0.x to 3.x) that enables Cross-Origin Resource Sharing (CORS) by adding appropriate HTTP headers. Version 0.0.3 is the latest and final release; the package has been abandoned in favor of the more popular 'cors' package. It allows configuration of allowed origins with flexible patterns (including scheme, subdomain, and port wildcards), as well as custom methods, headers, and max age. No longer maintained and incompatible with Express 4+ due to internal API changes and missing CORS preflight handling for non-simple requests.

web-framework http-networking auth-security

npm install express-cors

package ↗

INSTALL

IMPORT

SIG · EXPRESS-CORS

express-cors

web-frameworkjavascriptv0.0.3

Install

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Import

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Disk

—

Pass rate

0/ 6

Env Coverage0 / 6

glibc

18–22

musl

18–22

Install & Compatibility

Where this runs

tested against v? · npm install

Install × environment matrix

Each cell = how many times install + import succeeded across repeated harness runs. Partial = flaky.
glibc = Debian/Ubuntu slim · musl = Alpine Linux

musl

node 18–226 runs

build_error

glibc

node 18–226 runs

build_error

Code

Verified usage

Verified import paths — ran on the pinned version, not inferred.

default

✓ const cors = require('express-cors')

✗ import cors from 'express-cors'

This package is CommonJS-only and does not support ES modules.

cors function

✓ require('express-cors')

✗ require('express-cors').default

Module exports the middleware function directly; there is no default export.

default

✓ const cors = require('express-cors')

✗ const { cors } = require('express-cors')

No named exports; only the function itself is exported.

Set up Express middleware to allow CORS from example.com and subdomains, with custom methods and headers.

const express = require('express'); const cors = require('express-cors'); const app = express(); app.use(cors({ allowedOrigins: ['example.com', '*.example.com'], methods: ['GET', 'POST'], headers: ['Content-Type', 'Authorization'], maxAge: 3600 })); app.get('/', (req, res) => { res.send('Hello World!'); }); app.listen(3000, () => console.log('Server running on port 3000'));

Debug

Known issues

deprecatedexpress-cors is deprecated and no longer maintained. Use the cors package instead.

fix

Replace with 'cors' package: npm uninstall express-cors && npm install cors

affects: >=0.0.0

breakingexpress-cors does not support Express 4+; it relies on deprecated Express 3.x internal APIs (e.g., res.setHeader instead of res.set) and may cause errors.

fix

Migrate to cors package which supports Express 4+.

affects: >=0.0.0

gotchaexpress-cors does not handle non-simple CORS requests (preflight) automatically; the OPTIONS method must be explicitly handled.

fix

Add a separate OPTIONS route or use cors package which handles preflight automatically.

affects: >=0.0.0

gotchaThe allowedOrigins option does not support a boolean 'true' to allow any origin; each origin must be explicitly listed.

fix

Use '*' as an origin string if needed, but note that this package's pattern matching may behave unexpectedly.

affects: >=0.0.0

Errors

Common errors & fixes

cors is not defined

Using ES module import (import cors from 'express-cors') with a CommonJS-only package.

fix

Use require('express-cors') instead: const cors = require('express-cors');

TypeError: app.use() requires a middleware function

Passing incorrect configuration object or forgetting to call cors() as a function.

fix

Ensure you pass the options object to cors(): app.use(cors({ ... }))

Cannot find module 'express-cors'

Package not installed or missing in node_modules.

fix

Run: npm install express-cors

Upgrade

Version history

0.0.3latest on npm

Audit

Dependencies

No dependency data recorded yet.

Agent activity

19 hits · last 30 days

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Resources

packagehttps://www.npmjs.com/package/express-cors ↗