RequestFlow Pro — HTTP Request Header & Query Param Overrider

Effortlessly override, add, or modify HTTP request headers, query parameters, and upstream responses using URL matching.

RequestFlow Pro is a powerful, lightweight developer tool designed for software engineers, QA testers, and security professionals. It allows you to dynamically intercept, add, or override HTTP request headers and query parameters for external AJAX (XHR/Fetch) requests on the fly. 🚀 New Feature: Intercept and modify upstream server responses before they reach your web application! Whether you are debugging APIs, testing staging environments against production frontends, bypassing CORS constraints, or injecting temporary authentication tokens, RequestFlow Pro provides an intuitive interface to manage your network layer rules efficiently. 🌟 Key Features Flexible Network Injection: Easily add, modify, or completely override request headers and query string parameters. Upstream Response Modification: Intercept and alter server responses to test frontend UI edge cases and mock data payload changes. Targeted URL Matching: Define specific URL substrings so your rules only apply to the exact endpoints you want to target, preventing unintended side effects on other websites. High Performance Architecture: Built utilizing Chrome's native declarativeNetRequest engine. Rules are executed efficiently at the browser level without degrading page load speeds or draining system resources. Sleek Developer UX: A clean, minimal UI built with React makes enabling, disabling, and organizing your rules completely effortless. 🛠️ Common Use Cases API Authentication: Inject Authorization headers or custom API keys into third-party or backend requests without changing your local codebase. Environment Mocking: Append query parameters (such as debug flags, version overrides, or staging environments) to outgoing requests automatically. Frontend/Backend Decoupling: Point local frontend applications to different backend microservices seamlessly. ⚙️ How It Works For every rule you create, you can configure: Header/Query Param: The target key you want to inject or modify. Value: The value to be assigned to that key. URL Substring: The conditional trigger. The rule strictly applies only if the request URL contains this text. 🔒 Privacy, Security & Trust Your network data is sensitive. This extension runs entirely locally inside your browser using local storage. It does not track your browsing history, contains no external analytics scripts, and never sends data to remote servers. 100% Free: No hidden paywalls, no premium tiers. Free now, free always. Fully Open Source: Transparent and auditable. Review the code, submit issues, or contribute to the project on GitHub: https://github.com/paulb896/request-header-override-chrome-extension