fix: Fix broken shutdown handler

This is a #PATCH release.

cmd/app/shutdown.go

@@ -3,9 +3,7 @@ package app
 import (
 	"context"
 	"encoding/json"
-	"errors"
 	"fmt"
-	"io"
 	"net/http"
 	"os"
 )
@@ -19,22 +17,20 @@ func (k killer) String() string {
 
 type ShutdownHandler interface {
 	WatchForShutdown(server *http.Server)
-	shutdownHandler(w http.ResponseWriter, r *http.Request)
+	ServeHTTP(w http.ResponseWriter, r *http.Request)
 }
 
-type shutdown struct {
+type shutdownService struct {
 	sigCh chan os.Signal
 }
 
-func (s shutdown) WatchForShutdown(server *http.Server) {
+func (s shutdownService) WatchForShutdown(server *http.Server) {
 	/* Handles shutdown requests */
 	<-s.sigCh
 	err := server.Shutdown(context.Background())
 	if err != nil {
 		fmt.Fprintf(os.Stderr, "Server could not shut down gracefully: %s\n", err)
 		os.Exit(1)
-	} else {
-		os.Exit(0)
 	}
 }
 
@@ -42,36 +38,20 @@ type ShutdownRequest struct {
 	Restart bool `json:"restart"`
 }
 
-/* shutdownHandler will shutdown the HTTP server and exit the process by signaling to the shutdown channel */
-func (s shutdown) shutdownHandler(w http.ResponseWriter, r *http.Request) {
-	if r.Method != http.MethodPost {
-		w.Header().Set("Allow", http.MethodPost)
-		handleError(w, errors.New("Invalid request type"), "That request type is not allowed", http.StatusMethodNotAllowed)
-		return
-	}
+/* Shuts down the HTTP server and exit the process by signaling to the shutdown channel */
+func (s shutdownService) ServeHTTP(w http.ResponseWriter, r *http.Request) {
 
-	body, err := io.ReadAll(r.Body)
-	if err != nil {
-		handleError(w, err, "Could not read request body", http.StatusBadRequest)
-		return
-	}
-
-	var shutdownRequest ShutdownRequest
-	err = json.Unmarshal(body, &shutdownRequest)
-	if err != nil {
-		handleError(w, err, "Could not unmarshal data from request body", http.StatusBadRequest)
-		return
-	}
+	payload := r.Context().Value(payload("payload")).(*ShutdownRequest)
 
 	var text = "Shut down server"
-	if shutdownRequest.Restart {
+	if payload.Restart {
 		text = "Restarted server"
 	}
 
 	w.WriteHeader(http.StatusOK)
 	response := SuccessResponse{Message: text}
 
-	err = json.NewEncoder(w).Encode(response)
+	err := json.NewEncoder(w).Encode(response)
 	if err != nil {
 		handleError(w, err, "Could not encode response", http.StatusInternalServerError)
 	} else {