Implement error pages, improve request logging

cmd/app/main.go

@@ -6,20 +6,11 @@ import (
 	"encoding/base64"
 	"fmt"
 	"net/http"
-	"os"
-	"os/signal"
-	"strings"
-	"sync/atomic"
 	"time"
 
-	"github.com/knadh/koanf"
 	"github.com/knadh/koanf/parsers/toml"
 	"github.com/knadh/koanf/providers/confmap"
-	"github.com/knadh/koanf/providers/env"
-	"github.com/knadh/koanf/providers/file"
-	"github.com/knadh/koanf/providers/posflag"
 	log "github.com/sirupsen/logrus"
-	flag "github.com/spf13/pflag"
 
 	"git.cacert.org/oidc_login/app/handlers"
 	"git.cacert.org/oidc_login/app/services"
@@ -28,48 +19,21 @@ import (
 )
 
 func main() {
-	f := flag.NewFlagSet("config", flag.ContinueOnError)
-	f.Usage = func() {
-		fmt.Println(f.FlagUsages())
-		os.Exit(0)
-	}
-	f.StringSlice("conf", []string{"resource_app.toml"}, "path to one or more .toml files")
 	logger := log.New()
-	var err error
-
-	if err = f.Parse(os.Args[1:]); err != nil {
-		logger.Fatal(err)
-	}
-
-	config := koanf.New(".")
-
-	_ = config.Load(confmap.Provider(map[string]interface{}{
-		"server.port":        4000,
-		"server.name":        "app.cacert.localhost",
-		"server.key":         "certs/app.cacert.localhost.key",
-		"server.certificate": "certs/app.cacert.localhost.crt.pem",
-		"oidc.server":        "https://auth.cacert.localhost:4444/",
-		"session.path":       "sessions/app",
-		"i18n.languages":     []string{"en", "de"},
-	}, "."), nil)
-	cFiles, _ := f.GetStringSlice("conf")
-	for _, c := range cFiles {
-		if err := config.Load(file.Provider(c), toml.Parser()); err != nil {
-			logger.Fatalf("error loading config file: %s", err)
-		}
-	}
-	if err := config.Load(posflag.Provider(f, ".", config), nil); err != nil {
-		logger.Fatalf("error loading configuration: %s", err)
-	}
-	if err := config.Load(file.Provider("resource_app.toml"), toml.Parser()); err != nil && !os.IsNotExist(err) {
-		log.Fatalf("error loading config: %v", err)
-	}
-	const prefix = "RESOURCE_APP_"
-	if err := config.Load(env.Provider(prefix, ".", func(s string) string {
-		return strings.Replace(strings.ToLower(
-			strings.TrimPrefix(s, prefix)), "_", ".", -1)
-	}), nil); err != nil {
-		log.Fatalf("error loading config: %v", err)
+	config, err := commonServices.ConfigureApplication(
+		logger,
+		"RESOURCE_APP",
+		map[string]interface{}{
+			"server.port":        4000,
+			"server.name":        "app.cacert.localhost",
+			"server.key":         "certs/app.cacert.localhost.key",
+			"server.certificate": "certs/app.cacert.localhost.crt.pem",
+			"oidc.server":        "https://auth.cacert.localhost:4444/",
+			"session.path":       "sessions/app",
+			"i18n.languages":     []string{"en", "de"},
+		})
+	if err != nil {
+		log.Fatalf("error loading configuration: %v", err)
 	}
 
 	oidcServer := config.MustString("oidc.server")
@@ -151,6 +115,14 @@ func main() {
 	tracing := commonHandlers.Tracing(nextRequestId)
 	logging := commonHandlers.Logging(logger)
 	hsts := commonHandlers.EnableHSTS()
+	errorMiddleware, err := commonHandlers.ErrorHandling(
+		ctx,
+		logger,
+		"templates/app",
+	)
+	if err != nil {
+		logger.Fatalf("could not initialize request error handling: %v", err)
+	}
 
 	tlsConfig := &tls.Config{
 		ServerName: config.String("server.name"),
@@ -158,40 +130,12 @@ func main() {
 	}
 	server := &http.Server{
 		Addr:         serverAddr,
-		Handler:      tracing(logging(hsts(router))),
+		Handler:      tracing(logging(hsts(errorMiddleware(router)))),
 		ReadTimeout:  5 * time.Second,
 		WriteTimeout: 10 * time.Second,
 		IdleTimeout:  15 * time.Second,
 		TLSConfig:    tlsConfig,
 	}
 
-	done := make(chan bool)
-	quit := make(chan os.Signal, 1)
-	signal.Notify(quit, os.Interrupt)
-
-	go func() {
-		<-quit
-		logger.Infoln("Server is shutting down...")
-		atomic.StoreInt32(&commonHandlers.Healthy, 0)
-
-		ctx, cancel := context.WithTimeout(ctx, 30*time.Second)
-		defer cancel()
-
-		server.SetKeepAlivesEnabled(false)
-		if err := server.Shutdown(ctx); err != nil {
-			logger.Fatalf("Could not gracefully shutdown the server: %v\n", err)
-		}
-		close(done)
-	}()
-
-	logger.Infof("Server is ready to handle requests at https://%s/", server.Addr)
-	atomic.StoreInt32(&commonHandlers.Healthy, 1)
-	if err := server.ListenAndServeTLS(
-		config.String("server.certificate"), config.String("server.key"),
-	); err != nil && err != http.ErrServerClosed {
-		logger.Fatalf("Could not listen on %s: %v\n", server.Addr, err)
-	}
-
-	<-done
-	logger.Infoln("Server stopped")
+	commonHandlers.StartApplication(logger, ctx, server, config)
 }