Hands-On Dependency Injection in Go

Applying the method injection of context to the REST package

Finally, now for the key changes. First, we extract the context from the request:

// ServeHTTP implements http.Handlerfunc (h *RegisterHandler) ServeHTTP(response http.ResponseWriter, request *http.Request) {   // extract payload from request   requestPayload, err := h.extractPayload(request)   if err != nil {      // output error      response.WriteHeader(http.StatusBadRequest)      return   }   // call the business logic using the request data and context   id, err := h.register(request.Context(), requestPayload)   if err != nil {      // not need to log here as we can expect other layers to do so      response.WriteHeader(http.StatusBadRequest)      return   }   // happy path   response.Header().Add("Location", fmt.Sprintf