A simple dev HTTP/HTTPS proxy for replacing CORS headers.

Core features

• CORS header replacement
• Host mapping with named placeholders
• HTTPS support with auto-generated certificates
• Response mocking
• Script handler (Lua with a JSON module)
• HTTP/HTTPS proxy support
• Static file serving
• Response caching
• Request rewriting
• HAR traffic recording

The full documentation is on the wiki.

Quick install

Homebrew (macOS, Linux)

brew install evg4b/tap/uncors

Scoop (Windows)

scoop bucket add evg4b https://github.com/evg4b/scoop-bucket.git
scoop install evg4b/uncors

npm (cross-platform)

# Run without installing
npx -y uncors --from 'http://localhost:8080' --to 'https://github.com'
# Or add it to your project
npm install uncors --save-dev
# yarn add uncors --dev
# pnpm add -D uncors

Docker (cross-platform)

docker run -p 80:80 evg4b/uncors --interactive=false --from 'http://local.github.com' --to 'https://github.com'

Stew (cross-platform)

stew install evg4b/uncors

Other options, including prebuilt binaries and building from source, are described on the Installation wiki page.

Usage

Start a proxy from http://localhost:8080 to https://github.com:

uncors --from 'http://localhost:8080' --to 'https://github.com'

For larger setups, put the mappings in a YAML file and run uncors --config .uncors.yaml. The Configuration wiki page describes every option.

Caution

Rewriting CORS headers weakens browser security. UNCORS is meant for local development and testing. Do not run it in production or expose it as a remote proxy. It has not had a security review.

Stargazers over time

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