Add code to trigger module reinitialization on SIGUSR2

Author: foxcpp

maddy.go

@@ -376,6 +376,12 @@ func moduleStop(c *container.C) {
 func moduleMain(configPath string) error {
 	log.DefaultLogger.Msg("loading configuration...")
 
+	// Make path absolute to make sure we can still read it if current directory changes (in moduleConfigure).
+	configPath, err := filepath.Abs(configPath)
+	if err != nil {
+		return err
+	}
+
 	c, err := moduleConfigure(configPath)
 	if err != nil {
 		return err
@@ -389,7 +395,12 @@ func moduleMain(configPath string) error {
 	c.DefaultLogger.Msg("server started", "version", Version)
 
 	systemdStatus(SDReady, "Listening for incoming connections...")
-	handleSignals()
+	for handleSignals() {
+		systemdStatus(SDReloading, "Reloading state...")
+		hooks.RunHooks(hooks.EventReload)
+
+		c = moduleReload(c, configPath)
+	}
 
 	c.DefaultLogger.Msg("server stopping...")
 	systemdStatus(SDStopping, "Waiting for running transactions to complete...")
@@ -399,6 +410,33 @@ func moduleMain(configPath string) error {
 	return nil
 }
 
+func moduleReload(oldContainer *container.C, configPath string) *container.C {
+	oldContainer.DefaultLogger.Msg("reloading server...")
+
+	oldContainer.DefaultLogger.Msg("loading new configuration...")
+	newContainer, err := moduleConfigure(configPath)
+	if err != nil {
+		oldContainer.DefaultLogger.Error("failed to load new configuration", err)
+		return oldContainer
+	}
+
+	oldContainer.DefaultLogger.Msg("configuration loaded")
+
+	oldContainer.DefaultLogger.Msg("starting new server")
+	if err := moduleStart(newContainer); err != nil {
+		oldContainer.DefaultLogger.Error("failed to start new server", err)
+		container.Global = oldContainer
+		return oldContainer
+	}
+
+	newContainer.DefaultLogger.Msg("server started", "version", Version)
+	oldContainer.DefaultLogger.Msg("stopping server")
+	moduleStop(oldContainer)
+	oldContainer.DefaultLogger.Msg("server stopped")
+
+	return newContainer
+}
+
 func RegisterModules(c *container.C, globals map[string]interface{}, nodes []config.Node) (err error) {
 	var endpoints []struct {
 		Endpoint module.LifetimeModule

signal.go

@@ -36,9 +36,10 @@ import (
 // (SIGTERM, SIGHUP, SIGINT) will cause this function to return.
 //
 // SIGUSR1 will call reinitLogging without returning.
-func handleSignals() os.Signal {
+func handleSignals() (reload bool) {
 	sig := make(chan os.Signal, 5)
 	signal.Notify(sig, os.Interrupt, syscall.SIGTERM, syscall.SIGHUP, syscall.SIGINT, syscall.SIGUSR1, syscall.SIGUSR2)
+	defer signal.Stop(sig)
 
 	for {
 		switch s := <-sig; s {
@@ -48,10 +49,8 @@ func handleSignals() os.Signal {
 			hooks.RunHooks(hooks.EventLogRotate)
 			systemdStatus(SDReady, "Listening for incoming connections...")
 		case syscall.SIGUSR2:
-			log.Printf("signal received (%s), reloading state", s.String())
-			systemdStatus(SDReloading, "Reloading state...")
-			hooks.RunHooks(hooks.EventReload)
-			systemdStatus(SDReady, "Listening for incoming connections...")
+			log.Printf("signal received (%s), reloading configuration", s.String())
+			return true
 		default:
 			go func() {
 				s := handleSignals()
@@ -60,7 +59,7 @@ func handleSignals() os.Signal {
 			}()
 
 			log.Printf("signal received (%v), next signal will force immediate shutdown.", s)
-			return s
+			return false
 		}
 	}
 }