Support to reopen file based logs for rotation

server/log.go

@@ -1,10 +1,12 @@
-// Copyright 2012-2015 Apcera Inc. All rights reserved.
+// Copyright 2012-2016 Apcera Inc. All rights reserved.
 
 package server
 
 import (
 	"sync"
 	"sync/atomic"
+
+	"github.com/nats-io/gnatsd/logger"
 )
 
 // Package globals for performance checks
@@ -53,6 +55,29 @@ func (s *Server) SetLogger(logger Logger, debugFlag, traceFlag bool) {
 	log.Unlock()
 }
 
+// If the logger is a file based logger, close and re-open the file.
+// This allows for file rotation by 'mv'ing the file then signalling
+// the process to trigger this function.
+func (s *Server) ReOpenLogFile() {
+	// Check to make sure this is a file logger.
+	log.Lock()
+	ll := log.logger
+	log.Unlock()
+
+	if ll == nil {
+		Noticef("File log re-open ignored, no logger")
+		return
+	}
+	if s.opts.LogFile == "" {
+		Noticef("File log re-open ignored, not a file logger")
+	} else {
+		fileLog := logger.NewFileLogger(s.opts.LogFile,
+			s.opts.Logtime, s.opts.Debug, s.opts.Trace, true)
+		s.SetLogger(fileLog, s.opts.Debug, s.opts.Trace)
+		Noticef("File log re-opened")
+	}
+}
+
 // Noticef logs a notice statement
 func Noticef(format string, v ...interface{}) {
 	executeLogCall(func(logger Logger, format string, v ...interface{}) {

server/server.go

@@ -15,6 +15,7 @@ import (
 	"runtime"
 	"strconv"
 	"sync"
+	"syscall"
 	"time"
 
 	// Allow dynamic profiling.
@@ -187,13 +188,20 @@ func (s *Server) handleSignals() {
 		return
 	}
 	c := make(chan os.Signal, 1)
-	signal.Notify(c, os.Interrupt)
+
+	signal.Notify(c, syscall.SIGINT, syscall.SIGUSR1)
+
 	go func() {
 		for sig := range c {
-			Debugf("Trapped Signal; %v", sig)
-			// FIXME, trip running?
-			Noticef("Server Exiting..")
-			os.Exit(0)
+			Debugf("Trapped %q signal", sig)
+			switch sig {
+			case syscall.SIGINT:
+				Noticef("Server Exiting..")
+				os.Exit(0)
+			case syscall.SIGUSR1:
+				// File log re-open for rotating file logs.
+				s.ReOpenLogFile()
+			}
 		}
 	}()
 }