Implement proper signal handler

cmd/backer/main.go

@@ -41,6 +41,10 @@ func main() {
 		log.Fatalf("Failed to create server: %v", err)
 	}
 
+	// Setup signal handling for immediate shutdown.
+	log.Infof("Installing signal handler")
+	setupSignalHandler(server)
+
 	log.Infof("Starting backer version %s at %s", version, server.Addr)
 
 	if backer.C.NoHTTPS {
@@ -60,6 +64,8 @@ func main() {
 			log.Fatalf("Failed to start server: %v", err)
 		}
 	}
+
+	log.Infof("Server stopped")
 }
 
 // defaultConfigPath returns the default config file path based on the OS.

cmd/backer/sigHandler.go

@@ -0,0 +1,29 @@
+package main
+
+import (
+	"os"
+	"os/signal"
+	"syscall"
+
+	"backer/internal/backer"
+	"backer/internal/log"
+)
+
+// setupSignalHandler sets up signal handling for immediate shutdown.
+// SIGTERM is commonly sent by systemd, k8s, and other container orchestrators.
+// SIGINT is sent on Ctrl+C.
+func setupSignalHandler(server *backer.ServerWrapper) {
+	signalCh := make(chan os.Signal, 1)
+	signal.Notify(signalCh, os.Interrupt, syscall.SIGTERM)
+
+	go func() {
+		<-signalCh
+		log.Warnf("Shutdown signal received, shutting down immediately...")
+		// Close the embedded http.Server directly.
+		if closeErr := server.Close(); closeErr != nil {
+			log.Errorf("Error during server shutdown: %v", closeErr)
+		}
+	}()
+}
+
+/* vim: setlocal ft=go noet ai ts=4 sw=4 sts=4: */