🚀 REST API Client for Firefox

A lightweight, privacy‑focused HTTP client that works on Firefox Extension and Firefox for Android. Inspired by Postman, it lets you craft and send requests, inspect responses, and debug APIs directly from your browser – without leaving your tab.

✨ Features

• 🌐 All standard HTTP methods – GET, POST, PUT, DELETE, PATCH, HEAD, OPTIONS
• 📋 Custom headers – Add, edit, or remove headers on the fly
• 📦 Request body support – Send JSON, plain text, or any raw data
• 🎨 JSON syntax highlighting – View responses with colour‑coded keys, strings, numbers, and booleans
• 🔄 Raw / Pretty toggle – Switch between raw response text and a prettified, highlighted view
• 📊 Response metadata – See status code, time taken, and size at a glance
• 🔒 Privacy first – All requests are sent directly from your browser; no data ever leaves your device
• 📱 Cross‑platform – Works flawlessly on both Firefox desktop and Android (version 142+)
• ⚡ Fast & intuitive – Clean interface with method‑based colour hints and animated buttons

Screenshots

📦 Installation

From addons.mozilla.org (AMO)

1. Visit the REST API Client
2. Click Add to Firefox.
3. Confirm the installation.

🚀 How to Use

1. Click the REST API Client icon in the toolbar to open the popup.
2. Enter the URL you want to call.
3. Select the HTTP method from the dropdown – the button colour changes to match the method.
4. Add any required headers under the Headers tab (e.g., Content-Type, Authorization).
5. If the method supports a body (POST, PUT, PATCH), switch to the Body tab and enter your request data.
6. Click the big Send button.
7. View the response in the Response tab:
   • Pretty – JSON is formatted and syntax‑highlighted
   • Raw – shows the exact response text
8. Check the response status, time, and size below the response area.

🔐 Permissions & Privacy

This extension requests the following permissions:

• <all_urls> – Required to send HTTP requests to any URL you provide.
• tabs – Used to optionally pre‑fill the URL from the active tab (planned for a future update).

No data is ever collected, stored, or transmitted outside your browser.

• The URLs you enter and the responses you receive are processed locally.
• No analytics, tracking, or third‑party services are used.
• The extension declares data_collection_permissions: { "required": ["websiteContent"] } in its manifest, because it temporarily processes request/response data.

A full privacy policy is available here (link to your privacy policy).

🛠 Development

Prerequisites

• Firefox (desktop or Android)
• web-ext (optional, for building and testing)

Getting started

1. Clone the repository:

   git clone https://github.com/yourusername/rest-api-client-firefox.git
   cd rest-api-client-firefox

2. Make changes to the source files.
3. Test the extension temporarily using web-ext:

   web-ext run

4. Build a distributable .xpi package:

   web-ext build

Folder structure

rest-api-client-firefox/
├── icons/               # Extension icons (16, 32, 48, 128)
├── popup.html           # Main popup interface
├── popup.js             # Popup logic
├── popup.css            # Styling
├── background.js        # Background script (event page)
├── manifest.json        # Extension manifest
└── README.md            # This file

Security notes

• The JSON syntax highlighter uses DOMParser (safe, no innerHTML) after escaping <, >, and &.
• All dynamic content is sanitised or rendered via safe DOM methods.
• The extension complies with Firefox’s built‑in data collection consent system (Manifest V3).

📄 License

This project is licensed under the MIT License. See the LICENSE file for details.

🙋 Support & Feedback

• For issues, feature requests, or questions, please open an issue on GitHub.

Happy API testing! 🎉