errorHandler()

Turn an uncaught error anywhere downstream into a clean 500, with a server-side log and no leaked stack.

Use case

An unhandled throw in a middleware or handler should never crash the process or leak a stack trace to the client. errorHandler wraps the chain below it: on an error it logs the method, path, and error, then sends a tidy 500, in production without revealing the internal detail.

How it works

Registered first, it wraps everything after it. If a downstream middleware or handler throws, it catches the error, logs it server-side (method + path + error), and replies 500. With production: true (the default) the body is a generic { error: "Internal Server Error" }; with production: false the body includes the real error string, useful in development.

Configuration

Example

Notes

Register errorHandler first so it wraps the whole chain. rune also catches handler throws and returns 500 on its own; errorHandler adds the logging plus the production/dev shaping, and crucially covers the middleware chain, not just route handlers.

Next: httpsRedirect.