Netreq - Browser Extension for Request Redirection

A powerful Chrome/Brave/Edge browser extension that intercepts and redirects API requests from a source URL to a target URL while preserving all headers, parameters, and request bodies.

Features

✨ Request Interception & Redirection

• Intercept requests matching a source URL prefix
• Redirect them to a target URL transparently
• All headers, query parameters, and request bodies are preserved

🔐 Header Preservation

• All original request headers are automatically copied to redirected requests
• Authorization headers, cookies, and custom headers are maintained
• CORS headers are handled correctly

📝 Query Parameters & Path Preservation

• URL parameters and query strings are automatically included
• Request paths are properly appended to the target URL
• Full payload bodies are forwarded

🎛️ Easy Configuration

• Simple popup interface for quick setup
• Advanced options page for detailed configuration
• Enable/disable toggle for quick activation

📊 Debug Logging

• Real-time logging of intercepted requests
• Request details and redirect information
• Status tracking and configuration display

Installation

For Chrome/Brave/Edge:

1. Clone or download this repository
2. Open your browser and navigate to chrome://extensions/ (Chrome) or brave://extensions/ (Brave)
3. Enable "Developer mode" (toggle in top-right corner)
4. Click "Load unpacked" and select the extension folder
5. The extension will appear in your extensions list

For Firefox:

The extension uses Manifest V3 which is Chrome-based. Firefox support would require a Manifest V2 conversion.

Usage

Quick Setup

1. Click the Netreq icon in your browser toolbar
2. Enter Source URL Prefix: The URL prefix to intercept (e.g., https://backendhach.com)
3. Enter Target/Redirect URL: Where requests should go (e.g., https://staging-api.example.com)
4. Click "Save Configuration"
5. Enable the toggle to activate request redirection

Example

Configuration:

• Source Prefix: https://api.myapp.com
• Target URL: https://api.staging.com

Result:

• Request to: https://api.myapp.com/users/123?role=admin
• Gets redirected to: https://api.staging.com/users/123?role=admin
• All headers (Authorization, Content-Type, etc.) are preserved
• Request body (if POST/PUT/PATCH) is forwarded as-is

How It Works

Request Interception Flow

1. Browser initiates request
   ↓
2. Extension's background service worker intercepts it
   ↓
3. Checks if URL matches source prefix
   ↓
4. If match found:
   - Extracts endpoint/path from original URL
   - Constructs new URL with target URL + endpoint
   - Preserves all headers
   - Preserves request body
   ↓
5. Redirects request to target URL
   ↓
6. Browser sends request with all original details

File Structure

netreq-extension/
├── manifest.json        # Extension configuration and permissions
├── background.js        # Main request interception logic
├── popup.html          # Quick settings popup
├── popup.js            # Popup functionality
├── options.html        # Advanced settings page
├── options.js          # Options page functionality
├── styles.css          # Styling for popup and options
└── images/             # Extension icons (16x16, 48x48, 128x128)

Technical Details

Permissions Used

• webRequest - Intercept HTTP requests
• webRequestBlocking - Block and modify requests
• storage - Store configuration locally
• tabs - Access tab information
• webNavigation - Monitor page navigation

Key Components

Background Service Worker (background.js)

• Intercepts requests using chrome.webRequest.onBeforeRequest
• Modifies headers using chrome.webRequest.onBeforeSendHeaders
• Handles response headers with chrome.webRequest.onHeadersReceived
• Logs request completion and errors
• Manages configuration storage

Popup Interface (popup.html + popup.js)

• Quick toggle to enable/disable redirection
• Configure source and target URLs
• Display current status
• Auto-save functionality

Options Page (options.html + options.js)

• Detailed configuration interface
• Advanced settings
• Debug logging interface
• Import/export configuration
• Clear log functionality

Configuration Details

Storage Format

Configurations are stored in Chrome's local storage as JSON:

{
  "enabled": true,
  "sourcePrefix": "https://api.myapp.com",
  "targetUrl": "https://api.staging.com"
}

URL Matching

• Uses prefix matching (not full URL matching)
• Source prefix should include protocol (http/https)
• Trailing slashes matter: https://api.com ≠ https://api.com/

Advanced Features

Request Logging

The extension logs all intercepted requests to the browser console and the debug panel:

• Request URL
• Redirect target
• Response status code
• Any errors encountered

Header Handling

All headers are automatically preserved:

• Authorization headers (Bearer tokens, API keys, etc.)
• Content-Type headers
• Custom headers
• CORS headers
• Cookies

Request Body Preservation

• POST, PUT, PATCH request bodies are fully preserved
• JSON payloads are maintained
• Form data is preserved
• File uploads are handled correctly

Troubleshooting

Requests Not Being Redirected

1. Check if extension is enabled: Look at popup status
2. Verify source prefix: Make sure it exactly matches the request URL
3. Check configuration: Open options page to see saved settings
4. Look at debug log: Check the options page debug console for errors

Headers Not Copied

The extension copies headers automatically. If specific headers are missing:

1. Check browser console for errors
2. Verify the target server accepts the headers
3. Some security headers might be filtered by the browser

CORS Issues

If you see CORS errors:

1. The extension doesn't bypass CORS - it only redirects requests
2. The target server must accept requests from your origin
3. Configure appropriate CORS headers on the target server

Security Considerations

• The extension only operates on locally-stored configuration
• No data is sent to external servers
• All redirection happens locally in the browser
• Configuration is stored only in Chrome's local storage

Limitations

• Manifest V3 only (Chrome/Brave/Edge)
• Cannot redirect WebSocket connections (only HTTP/HTTPS)
• Cross-origin redirects may fail due to browser security restrictions
• Cannot modify some security-related headers

Development

Making Changes

1. Edit the relevant file (background.js, popup.js, etc.)
2. Reload the extension in chrome://extensions/
3. Test in your browser

Testing

1. Open the extension popup to check basic functionality
2. Open the options page to view debug logs
3. Open DevTools (F12) → Background page to see background script logs
4. Monitor Network tab to verify redirects

License

This extension is provided as-is for personal and educational use.

Support & Issues

For issues or feature requests, please check:

1. Debug log in options page
2. Browser console for errors
3. Ensure configuration is correct
4. Verify target URL is accessible

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Version: 1.0.0
Compatibility: Chrome 88+, Brave, Edge, other Chromium-based browsers