Do not support SIGUSR1 and SIGUSR2 syscall handling in windows

Signed-off-by: Ying Li <ying.li@docker.com>

cmd/notary-server/config.go

@@ -3,12 +3,9 @@ package main
 import (
 	"crypto/tls"
 	"fmt"
-	"os"
-	"os/signal"
 	"path"
 	"strconv"
 	"strings"
-	"syscall"
 	"time"
 
 	"github.com/Sirupsen/logrus"
@@ -290,31 +287,3 @@ func parseServerConfig(configFilePath string, hRegister healthRegister, doBootst
 		ConsistentCacheControlConfig: consistentCache,
 	}, nil
 }
-
-func setupSignalTrap() {
-	c := make(chan os.Signal, 1)
-	signal.Notify(c, notary.NotarySupportedSignals...)
-	go func() {
-		for {
-			signalHandle(<-c)
-		}
-	}()
-}
-
-// signalHandle will increase/decrease the logging level via the signal we get.
-func signalHandle(sig os.Signal) {
-	switch sig {
-	case syscall.SIGUSR1:
-		if err := utils.AdjustLogLevel(true); err != nil {
-			fmt.Printf("Attempt to increase log level failed, will remain at %s level, error: %s\n", logrus.GetLevel(), err)
-			return
-		}
-	case syscall.SIGUSR2:
-		if err := utils.AdjustLogLevel(false); err != nil {
-			fmt.Printf("Attempt to decrease log level failed, will remain at %s level, error: %s\n", logrus.GetLevel(), err)
-			return
-		}
-	}
-
-	fmt.Println("Successfully setting log level to ", logrus.GetLevel())
-}

cmd/notary-server/main.go

@@ -7,10 +7,12 @@ import (
 	"net/http"
 	_ "net/http/pprof"
 	"os"
+	"os/signal"
 
 	"github.com/Sirupsen/logrus"
 	"github.com/docker/distribution/health"
 	"github.com/docker/notary/server"
+	"github.com/docker/notary/utils"
 	"github.com/docker/notary/version"
 )
 
@@ -61,7 +63,10 @@ func main() {
 		logrus.Fatal(err.Error())
 	}
 
-	setupSignalTrap()
+	c := utils.SetupSignalTrap(utils.LogLevelSignalHandle)
+	if c != nil {
+		defer signal.Stop(c)
+	}
 
 	if flagStorage.doBootstrap {
 		err = bootstrap(ctx)

cmd/notary-server/main_test.go

@@ -6,14 +6,11 @@ import (
 	"fmt"
 	"io/ioutil"
 	"os"
-	"path/filepath"
 	"reflect"
 	"strings"
-	"syscall"
 	"testing"
 	"time"
 
-	"github.com/Sirupsen/logrus"
 	"github.com/docker/distribution/health"
 	"github.com/docker/notary"
 	"github.com/docker/notary/server/storage"
@@ -416,30 +413,3 @@ func TestSampleConfig(t *testing.T) {
 	// once for the DB, once for the trust service
 	require.Equal(t, registerCalled, 2)
 }
-
-func TestSignalHandle(t *testing.T) {
-	tempdir, err := ioutil.TempDir("", "test-signal-handle")
-	require.NoError(t, err)
-	defer os.RemoveAll(tempdir)
-	f, err := os.Create(filepath.Join(tempdir, "testSignalHandle.json"))
-	require.NoError(t, err)
-
-	f.WriteString(`{"logging": {"level": "info"}}`)
-
-	v := viper.New()
-	utils.SetupViper(v, "envPrefix")
-	err = utils.ParseViper(v, f.Name())
-	require.NoError(t, err)
-
-	// Info + SIGUSR1 -> Debug
-	signalHandle(syscall.SIGUSR1)
-	require.Equal(t, logrus.GetLevel(), logrus.DebugLevel)
-
-	// Debug + SIGUSR1 -> Debug
-	signalHandle(syscall.SIGUSR1)
-	require.Equal(t, logrus.GetLevel(), logrus.DebugLevel)
-
-	// Debug + SIGUSR2-> Info
-	signalHandle(syscall.SIGUSR2)
-	require.Equal(t, logrus.GetLevel(), logrus.InfoLevel)
-}

cmd/notary-signer/main.go

@@ -6,8 +6,10 @@ import (
 	"log"
 	"net/http"
 	"os"
+	"os/signal"
 
 	"github.com/Sirupsen/logrus"
+	"github.com/docker/notary/utils"
 	"github.com/docker/notary/version"
 	_ "github.com/go-sql-driver/mysql"
 )
@@ -66,6 +68,11 @@ func main() {
 		log.Println("RPC server listening on", signerConfig.GRPCAddr)
 	}
 
+	c := utils.SetupSignalTrap(utils.LogLevelSignalHandle)
+	if c != nil {
+		defer signal.Stop(c)
+	}
+
 	grpcServer.Serve(lis)
 }
 

const.go

@@ -1,10 +1,6 @@
 package notary
 
-import (
-	"os"
-	"syscall"
-	"time"
-)
+import "time"
 
 // application wide constants
 const (
@@ -81,11 +77,3 @@ var NotaryDefaultExpiries = map[string]time.Duration{
 	"snapshot":  NotarySnapshotExpiry,
 	"timestamp": NotaryTimestampExpiry,
 }
-
-// NotarySupportedSignals contains the signals we would like to capture:
-// - SIGUSR1, indicates a increment of the log level.
-// - SIGUSR2, indicates a decrement of the log level.
-var NotarySupportedSignals = []os.Signal{
-	syscall.SIGUSR1,
-	syscall.SIGUSR2,
-}

const_nowindows.go

@@ -0,0 +1,16 @@
+// +build !windows
+
+package notary
+
+import (
+	"os"
+	"syscall"
+)
+
+// NotarySupportedSignals contains the signals we would like to capture:
+// - SIGUSR1, indicates a increment of the log level.
+// - SIGUSR2, indicates a decrement of the log level.
+var NotarySupportedSignals = []os.Signal{
+	syscall.SIGUSR1,
+	syscall.SIGUSR2,
+}

const_windows.go

@@ -0,0 +1,8 @@
+// +build windows
+
+package notary
+
+import "os"
+
+// NotarySupportedSignals does not contain any signals, because SIGUSR1/2 are not supported on windows
+var NotarySupportedSignals = []os.Signal{}

docs/reference/signer-config.md

@@ -210,6 +210,42 @@ The environment variables for the older passwords are optional, but Notary
 Signer will not be able to decrypt older keys if they are not provided, and
 attempts to sign data using those keys will fail.
 
+## Hot logging level reload
+We don't support completely reloading notary signer configuration files yet at present. What we support for now is:
+- increase logging level by signaling `SIGUSR1`
+- decrease logging level by signaling `SIGUSR2`
+
+Example:
+
+To increase logging level
+```
+$ kill -s SIGUSR1 PID
+
+or
+
+$ docker exec -i CONTAINER_ID kill -s SIGUSR1 PID
+```
+
+To decrease logging level
+```
+$ kill -s SIGUSR2 PID
+
+or
+
+$ docker exec -i CONTAINER_ID kill -s SIGUSR2 PID
+```
+PID is the process id of `notary-signer` and it may not the PID 1 process if you are running
+the container with some kind of wrapper startup script or something.
+
+You can get the PID of `notary-signer` through
+```
+$ docker exec CONTAINER_ID ps aux
+
+or
+
+$ ps aux | grep "notary-signer -config" | grep -v "grep"
+```
+
 
 ## Related information
 

utils/configuration.go

@@ -5,6 +5,8 @@ package utils
 import (
 	"crypto/tls"
 	"fmt"
+	"os"
+	"os/signal"
 	"path/filepath"
 	"strings"
 
@@ -244,3 +246,20 @@ func AdjustLogLevel(increment bool) error {
 	logrus.SetLevel(lvl)
 	return nil
 }
+
+// SetupSignalTrap is a utility to trap supported signals hand handle them (currently by increasing logging)
+func SetupSignalTrap(handler func(os.Signal)) chan os.Signal {
+	if len(notary.NotarySupportedSignals) == 0 {
+		return nil
+
+	}
+	c := make(chan os.Signal, 1)
+	signal.Notify(c, notary.NotarySupportedSignals...)
+	go func() {
+		for {
+			handler(<-c)
+		}
+	}()
+
+	return c
+}

utils/configuration_nowindows.go

@@ -0,0 +1,29 @@
+// +build !windows
+
+package utils
+
+import (
+	"fmt"
+	"os"
+	"syscall"
+
+	"github.com/Sirupsen/logrus"
+)
+
+// LogLevelSignalHandle will increase/decrease the logging level via the signal we get.
+func LogLevelSignalHandle(sig os.Signal) {
+	switch sig {
+	case syscall.SIGUSR1:
+		if err := AdjustLogLevel(true); err != nil {
+			fmt.Printf("Attempt to increase log level failed, will remain at %s level, error: %s\n", logrus.GetLevel(), err)
+			return
+		}
+	case syscall.SIGUSR2:
+		if err := AdjustLogLevel(false); err != nil {
+			fmt.Printf("Attempt to decrease log level failed, will remain at %s level, error: %s\n", logrus.GetLevel(), err)
+			return
+		}
+	}
+
+	fmt.Println("Successfully setting log level to ", logrus.GetLevel())
+}

utils/configuration_nowindows_test.go

@@ -0,0 +1,33 @@
+// +build !windows
+
+package utils
+
+import (
+	"io/ioutil"
+	"os"
+	"syscall"
+	"testing"
+
+	"github.com/Sirupsen/logrus"
+	"github.com/stretchr/testify/require"
+)
+
+func TestLogLevelSignalHandle(t *testing.T) {
+	tempdir, err := ioutil.TempDir("", "test-signal-handle")
+	require.NoError(t, err)
+	defer os.RemoveAll(tempdir)
+
+	logrus.SetLevel(logrus.InfoLevel)
+
+	// Info + SIGUSR1 -> Debug
+	LogLevelSignalHandle(syscall.SIGUSR1)
+	require.Equal(t, logrus.GetLevel(), logrus.DebugLevel)
+
+	// Debug + SIGUSR1 -> Debug
+	LogLevelSignalHandle(syscall.SIGUSR1)
+	require.Equal(t, logrus.GetLevel(), logrus.DebugLevel)
+
+	// Debug + SIGUSR2-> Info
+	LogLevelSignalHandle(syscall.SIGUSR2)
+	require.Equal(t, logrus.GetLevel(), logrus.InfoLevel)
+}

utils/configuration_test.go

@@ -6,8 +6,10 @@ import (
 	"fmt"
 	"io/ioutil"
 	"os"
+	"os/signal"
 	"path/filepath"
 	"reflect"
+	"syscall"
 	"testing"
 
 	"github.com/Sirupsen/logrus"
@@ -560,3 +562,28 @@ func TestAdjustLogLevel(t *testing.T) {
 	err = AdjustLogLevel(optDecrement)
 	require.Error(t, err)
 }
+
+func TestSetSignalTrap(t *testing.T) {
+	var signalsPassedOn map[string]struct{}
+
+	signalHandler := func(s os.Signal) {
+		signalsPassedOn := make(map[string]struct{})
+		signalsPassedOn[s.String()] = struct{}{}
+	}
+	c := SetupSignalTrap(signalHandler)
+
+	if len(notary.NotarySupportedSignals) == 0 { // currently, windows only
+		require.Nil(t, c)
+	} else {
+		require.NotNil(t, c)
+		defer signal.Stop(c)
+	}
+
+	for _, s := range notary.NotarySupportedSignals {
+		syscallSignal, ok := s.(syscall.Signal)
+		require.True(t, ok)
+		require.NoError(t, syscall.Kill(syscall.Getpid(), syscallSignal))
+		require.Len(t, signalsPassedOn, 0)
+		require.NotNil(t, signalsPassedOn[s.String()])
+	}
+}

utils/configuration_windows.go

@@ -0,0 +1,9 @@
+// +build windows
+
+package utils
+
+import "os"
+
+// LogLevelSignalHandle will do nothing, because we aren't currently supporting signal handling in windows
+func LogLevelSignalHandle(sig os.Signal) {
+}