refactor: fix code duplication in keyshare server starting

irma/cmd/keyshare-myirma.go

 package cmd
 
 import (
-	"context"
-	"fmt"
-	"net/http"
-	"os"
-	"os/signal"
-	"syscall"
-
 	irma "github.com/privacybydesign/irmago"
 	"github.com/privacybydesign/irmago/server"
 	"github.com/privacybydesign/irmago/server/keyshare/myirmaserver"
@@ -21,55 +14,13 @@ var myirmadCmd = &cobra.Command{
 	Run: func(command *cobra.Command, args []string) {
 		conf := configureMyirmad(command)
 
-		// Determine full listening address.
-		fullAddr := fmt.Sprintf("%s:%d", viper.GetString("listen-addr"), viper.GetInt("port"))
-
-		// Load TLS configuration
-		TLSConfig := configureTLS()
-
 		// Create main server
 		myirmaServer, err := myirmaserver.New(conf)
 		if err != nil {
 			die("", err)
 		}
 
-		serv := &http.Server{
-			Addr:      fullAddr,
-			Handler:   myirmaServer.Handler(),
-			TLSConfig: TLSConfig,
-		}
-
-		stopped := make(chan struct{})
-		interrupt := make(chan os.Signal, 1)
-		signal.Notify(interrupt, os.Interrupt, syscall.SIGTERM)
-
-		go func() {
-			if TLSConfig != nil {
-				err = serv.ListenAndServeTLS("", "")
-			} else {
-				err = serv.ListenAndServe()
-			}
-			conf.Logger.Debug("Server stopped")
-			stopped <- struct{}{}
-		}()
-
-		for {
-			select {
-			case <-interrupt:
-				conf.Logger.Debug("Caught interrupt")
-				err = serv.Shutdown(context.Background())
-				if err != nil {
-					_ = server.LogError(err)
-				}
-				myirmaServer.Stop()
-				conf.Logger.Debug("Sent stop signal to server")
-			case <-stopped:
-				conf.Logger.Info("Exiting")
-				close(stopped)
-				close(interrupt)
-				return
-			}
-		}
+		runServer(myirmaServer, conf.Logger)
 	},
 }
 

irma/cmd/keyshare-root.go

 package cmd
 
-import "github.com/sietseringers/cobra"
+import (
+	"context"
+	"fmt"
+	"net/http"
+	"os"
+	"os/signal"
+	"syscall"
+
+	"github.com/privacybydesign/irmago/server"
+	"github.com/sietseringers/cobra"
+	"github.com/sietseringers/viper"
+	"github.com/sirupsen/logrus"
+)
 
 var keyshareRoot = &cobra.Command{
 	Use:   "keyshare",
@@ -10,3 +22,58 @@ var keyshareRoot = &cobra.Command{
 func init() {
 	RootCmd.AddCommand(keyshareRoot)
 }
+
+type stoppableServer interface {
+	Handler() http.Handler
+	Stop()
+}
+
+func runServer(serv stoppableServer, logger *logrus.Logger) {
+	// Determine full listening address.
+	fullAddr := fmt.Sprintf("%s:%d", viper.GetString("listen-addr"), viper.GetInt("port"))
+
+	// Load TLS configuration
+	TLSConfig := configureTLS()
+
+	httpServer := &http.Server{
+		Addr:      fullAddr,
+		Handler:   serv.Handler(),
+		TLSConfig: TLSConfig,
+	}
+
+	stopped := make(chan struct{})
+	interrupt := make(chan os.Signal, 1)
+	signal.Notify(interrupt, os.Interrupt, syscall.SIGTERM)
+
+	go func() {
+		var err error
+		if TLSConfig != nil {
+			err = server.FilterStopError(httpServer.ListenAndServeTLS("", ""))
+		} else {
+			err = server.FilterStopError(httpServer.ListenAndServe())
+		}
+		logger.Debug("Server stopped")
+		if err != nil {
+			_ = server.LogError(err)
+		}
+		stopped <- struct{}{}
+	}()
+
+	for {
+		select {
+		case <-interrupt:
+			logger.Debug("Caught interrupt")
+			err := httpServer.Shutdown(context.Background())
+			if err != nil {
+				_ = server.LogError(err)
+			}
+			serv.Stop()
+			logger.Debug("Sent stop signal to server")
+		case <-stopped:
+			logger.Info("Exiting")
+			close(stopped)
+			close(interrupt)
+			return
+		}
+	}
+}

irma/cmd/keyshare-server.go

 package cmd
 
 import (
-	"context"
-	"fmt"
-	"net/http"
-	"os"
-	"os/signal"
-	"syscall"
-
 	irma "github.com/privacybydesign/irmago"
 	"github.com/privacybydesign/irmago/server"
 	"github.com/privacybydesign/irmago/server/keyshare/keyshareserver"
@@ -21,55 +14,13 @@ var keysharedCmd = &cobra.Command{
 	Run: func(command *cobra.Command, args []string) {
 		conf := configureKeyshared(command)
 
-		// Determine full listening address.
-		fullAddr := fmt.Sprintf("%s:%d", viper.GetString("listen-addr"), viper.GetInt("port"))
-
-		// Load TLS configuration
-		TLSConfig := configureTLS()
-
 		// Create main server
 		keyshareServer, err := keyshareserver.New(conf)
 		if err != nil {
 			die("", err)
 		}
 
-		serv := &http.Server{
-			Addr:      fullAddr,
-			Handler:   keyshareServer.Handler(),
-			TLSConfig: TLSConfig,
-		}
-
-		stopped := make(chan struct{})
-		interrupt := make(chan os.Signal, 1)
-		signal.Notify(interrupt, os.Interrupt, syscall.SIGTERM)
-
-		go func() {
-			if TLSConfig != nil {
-				err = serv.ListenAndServeTLS("", "")
-			} else {
-				err = serv.ListenAndServe()
-			}
-			conf.Logger.Debug("Server stopped")
-			stopped <- struct{}{}
-		}()
-
-		for {
-			select {
-			case <-interrupt:
-				conf.Logger.Debug("Caught interrupt")
-				err = serv.Shutdown(context.Background())
-				if err != nil {
-					_ = server.LogError(err)
-				}
-				keyshareServer.Stop()
-				conf.Logger.Debug("Sent stop signal to server")
-			case <-stopped:
-				conf.Logger.Info("Exiting")
-				close(stopped)
-				close(interrupt)
-				return
-			}
-		}
+		runServer(keyshareServer, conf.Logger)
 	},
 }
 

server/api.go

@@ -549,3 +549,10 @@ func ParseBody(w http.ResponseWriter, r *http.Request, input interface{}) error
 	}
 	return nil
 }
+
+func FilterStopError(err error) error {
+	if err == http.ErrServerClosed {
+		return nil
+	}
+	return err
+}

server/requestorserver/server.go

@@ -117,19 +117,12 @@ func (s *Server) startServer(handler http.Handler, name, addr string, port int,
 
 	if tlsConf != nil {
 		s.conf.Logger.Info(name, " TLS enabled")
-		return filterStopError(serv.ListenAndServeTLS("", ""))
+		return server.FilterStopError(serv.ListenAndServeTLS("", ""))
 	} else {
-		return filterStopError(serv.ListenAndServe())
+		return server.FilterStopError(serv.ListenAndServe())
 	}
 }
 
-func filterStopError(err error) error {
-	if err == http.ErrServerClosed {
-		return nil
-	}
-	return err
-}
-
 func (s *Server) Stop() {
 	s.irmaserv.Stop()
 	s.stop <- struct{}{}