GitHub - coder/httpjail: HTTP(s) request filter for processes

# Allow only requests to github.com (JS)
httpjail --js "r.host === 'github.com'" -- your-app

# Load JS from a file (auto-reloads on file changes)
echo "/^api\\.example\\.com$/.test(r.host) && r.method === 'GET'" > rules.js
httpjail --js-file rules.js -- curl https://api.example.com/health
# File changes are detected and reloaded automatically on each request

# Log requests to a file
httpjail --request-log requests.log --js "true" -- npm install
# Log format: "<timestamp> <+/-> <METHOD> <URL>" (+ = allowed, - = blocked)

# Use shell script for request evaluation (process per request)
httpjail --sh "/path/to/script.sh" -- ./my-app
# Script receives env vars: HTTPJAIL_URL, HTTPJAIL_METHOD, HTTPJAIL_HOST, etc.
# Exit code 0 allows, non-zero blocks

# Use line processor for request evaluation (efficient persistent process)
httpjail --proc /path/to/filter.py -- ./my-app
# Program receives JSON on stdin (one per line) and outputs allow/deny decisions
# stdin  -> {"method": "GET", "url": "https://api.github.com", "host": "api.github.com", ...}
# stdout -> true

# Run as standalone proxy server (no command execution) and allow all
httpjail --server --js "true"
# Server defaults to ports 8080 (HTTP) and 8443 (HTTPS)
# Configure your application:
# HTTP_PROXY=http://localhost:8080 HTTPS_PROXY=http://localhost:8443

# Run Docker containers with network isolation (Linux only)
httpjail --js "r.host === 'api.github.com'" --docker-run -- --rm alpine:latest wget -qO- https://api.github.com