pantafive/smocker

Smocker is a tool that lets you create fake HTTP servers for testing. Instead of calling real APIs during development or testing, you point your code at Smocker, tell it what responses to send back, and it handles the requests. This speeds up testing, lets you test error scenarios easily, and means you don't depend on external services being available. The way it works is straightforward: Smocker runs two ports side by side. One port (8080 by default) is the mock server itself, the fake API your code talks to. The other port (8081) is the control panel where you define what responses should be sent back. You describe your mocks in simple YAML or JSON files, listing the request path and method you want to handle, then the response status code, headers, and body you want to return. Once you upload these mocks to the control port, the mock server immediately knows how to respond to those requests. There's also a web interface on the control port so you can see what mocks are registered, view a history of requests that came in, and reset everything without restarting. You'd use this if you're building a frontend or backend service that depends on calling other APIs. During development, you might not want to hit the real payment processor, email service, or third-party data provider. Smocker lets you simulate those dependencies with whatever responses you need. Testers love it because they can easily set up scenarios, like testing what happens when an API returns a 500 error, or when a response is delayed. It also works well in CI/CD pipelines where you need isolated, repeatable test environments. The project is written in Go for the backend and includes a TypeScript/React frontend. You can run it as a standalone binary or as a Docker container, making it easy to drop into existing workflows. The README doesn't detail advanced features, but links to fuller documentation at smocker.dev for anything beyond the basics.