inanzzz | Panic recovery middleware for Golang HTTP server

You can use example below to recover from panic and let your HTTP server carry on serving requests otherwise it will crash. Any panic is a kind of internal error so we will return 500 response in such case.

Middleware

If you cause a panic on purpose in one of your endpoints and call it, you will see that the response will be 500 Internal Server Error.

package pkg

import (
	"net/http"
)

func PanicRecovery(handler http.Handler) http.Handler {
	return http.HandlerFunc(func(rw http.ResponseWriter, rq *http.Request) {
		defer func() {
			if err := recover(); err != nil {
				log.Error(err)

				// To avoid 'superfluous response.WriteHeader call' error
				if rw.Header().Get("Content-Type") == "" {
					rw.WriteHeader(http.StatusInternalServerError)
				}
			}
		}()

		handler.ServeHTTP(rw, rq)
	})
}

return &http.Server{Addr: ":8080", Handler: pkg.PanicRecovery(yourRouter)}