OpenReq

OpenReq is an open-source API client for building, testing, and debugging HTTP requests with no limits or mandatory registration. It offers a Python script engine, AI-powered collection generation, a WebSocket client, visual test flows, and full support for environments and OAuth 2.0 authentication.

★★★★★

5.0(1 ratings)

• Tabbed request builder. The workspace allows you to handle multiple requests simultaneously in separate tabs. It supports all HTTP methods, query parameters, headers, and bodies in JSON, XML, form, or URL-encoded data formats. Path parameters are defined using the {{variable}} syntax.
• Five built-in authentication methods. In addition to Bearer token, Basic Auth, and API Key, it implements the complete OAuth 2.0 flow with the Authorization Code, Client Credentials, and PKCE grant types. Token exchange is performed within the interface without relying on external services.
• Pre- and post-request scripts in Python. The scripting engine executes Python code with access to the req object. It includes functions like req.test() for assertions, req.expect() for chained validations, req.variables for persistence, and req.sendRequest() to launch additional requests from the script.
• Environments and variables. Management of variables by environment (DEVELOPMENT, TESTING, PRODUCTION) with separate values and secret protection. Environment switching is done from the top bar, and variables can be inserted into any field using the {{variable}} syntax.
• Automatic code generation. Converts any configured request into ready-to-use code. Supported formats are cURL, Python (requests), JavaScript (fetch and axios), Go, Java, C#, and PHP. The generated code exactly reflects the selected headers, body, and method.
• AI assistant for collections. When pasting a URL with OpenAPI or Swagger documentation, the assistant analyzes the content and automatically generates the endpoints with their methods, paths, headers, and example bodies. The user reviews the detected items and selects which ones to import.
• Response viewer with multiple modes. The server response is displayed in Pretty (formatted), Raw, Tree (collapsible JSON tree), and Preview modes for HTML or SVG. Status code, response time, and size are included.
• Built-in WebSocket proxy. Connect to WebSocket servers from the same interface. Send and receive messages with timestamps and direction (sent/received) without needing additional tools.
• Collection import and export. Import data from Postman v2.1 format, OpenAPI 3.0+ specifications, or raw cURL commands. Collections can be exported back to Postman format for migration or backup.
• Visual test builder. A graphical canvas allows you to assemble complex test flows. Nodes (request, assertion, condition, delay, script, loop) are dragged from the palette and visually connected. Execution shows animated edges and per-node results in real time.
• George AI agent. An integrated conversational assistant that knows the entire scripting API. George can write scripts, debug assertions, explain responses, or generate test flows through real-time chat with conversation history.
• Integration with Ollama. Allows AI functions to be run completely locally using Ollama. The client detects available models and can switch between OpenAI and Ollama without data leaving the machine.

OpenReq began its development in 2024 and is primarily written in Python with FastAPI for the backend, while the frontend uses React with TypeScript. The application is published under the MIT license by its creator, n1kozor, and fosters a community around self-hosting. The program relies on SQLite as its database and Docker for simplified deployment.

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