pkg: support structured logger

Signed-off-by: Gyuho Lee <gyuhox@gmail.com>

pkg/fileutil/purge.go

@@ -20,14 +20,16 @@ import (
 	"sort"
 	"strings"
 	"time"
+
+	"go.uber.org/zap"
 )
 
-func PurgeFile(dirname string, suffix string, max uint, interval time.Duration, stop <-chan struct{}) <-chan error {
+func PurgeFile(lg *zap.Logger, dirname string, suffix string, max uint, interval time.Duration, stop <-chan struct{}) <-chan error {
-	return purgeFile(dirname, suffix, max, interval, stop, nil)
+	return purgeFile(lg, dirname, suffix, max, interval, stop, nil)
 }
 
 // purgeFile is the internal implementation for PurgeFile which can post purged files to purgec if non-nil.
-func purgeFile(dirname string, suffix string, max uint, interval time.Duration, stop <-chan struct{}, purgec chan<- string) <-chan error {
+func purgeFile(lg *zap.Logger, dirname string, suffix string, max uint, interval time.Duration, stop <-chan struct{}, purgec chan<- string) <-chan error {
 	errC := make(chan error, 1)
 	go func() {
 		for {
@@ -55,11 +57,19 @@ func purgeFile(dirname string, suffix string, max uint, interval time.Duration,
 					return
 				}
 				if err = l.Close(); err != nil {
+					if lg != nil {
+						lg.Warn("failed to unlock/close", zap.String("path", l.Name()), zap.Error(err))
+					} else {
 						plog.Errorf("error unlocking %s when purging file (%v)", l.Name(), err)
+					}
 					errC <- err
 					return
 				}
+				if lg != nil {
+					lg.Info("purged", zap.String("path", f))
+				} else {
 					plog.Infof("purged file %s successfully", f)
+				}
 				newfnames = newfnames[1:]
 			}
 			if purgec != nil {

pkg/fileutil/purge_test.go

@@ -22,6 +22,8 @@ import (
 	"reflect"
 	"testing"
 	"time"
+
+	"go.uber.org/zap"
 )
 
 func TestPurgeFile(t *testing.T) {
@@ -43,7 +45,7 @@ func TestPurgeFile(t *testing.T) {
 	stop, purgec := make(chan struct{}), make(chan string, 10)
 
 	// keep 3 most recent files
-	errch := purgeFile(dir, "test", 3, time.Millisecond, stop, purgec)
+	errch := purgeFile(zap.NewExample(), dir, "test", 3, time.Millisecond, stop, purgec)
 	select {
 	case f := <-purgec:
 		t.Errorf("unexpected purge on %q", f)
@@ -114,7 +116,7 @@ func TestPurgeFileHoldingLockFile(t *testing.T) {
 	}
 
 	stop, purgec := make(chan struct{}), make(chan string, 10)
-	errch := purgeFile(dir, "test", 3, time.Millisecond, stop, purgec)
+	errch := purgeFile(zap.NewExample(), dir, "test", 3, time.Millisecond, stop, purgec)
 
 	for i := 0; i < 5; i++ {
 		select {

pkg/osutil/interrupt_unix.go

@@ -21,6 +21,8 @@ import (
 	"os/signal"
 	"sync"
 	"syscall"
+
+	"go.uber.org/zap"
 )
 
 // InterruptHandler is a function that is called on receiving a
@@ -43,7 +45,7 @@ func RegisterInterruptHandler(h InterruptHandler) {
 }
 
 // HandleInterrupts calls the handler functions on receiving a SIGINT or SIGTERM.
-func HandleInterrupts() {
+func HandleInterrupts(lg *zap.Logger) {
 	notifier := make(chan os.Signal, 1)
 	signal.Notify(notifier, syscall.SIGINT, syscall.SIGTERM)
 
@@ -57,7 +59,11 @@ func HandleInterrupts() {
 
 		interruptExitMu.Lock()
 
+		if lg != nil {
+			lg.Info("received signal; shutting down", zap.String("signal", sig.String()))
+		} else {
 			plog.Noticef("received %v signal, shutting down...", sig)
+		}
 
 		for _, h := range ihs {
 			h()

pkg/osutil/interrupt_windows.go

@@ -16,7 +16,11 @@
 
 package osutil
 
-import "os"
+import (
+	"os"
+
+	"go.uber.org/zap"
+)
 
 type InterruptHandler func()
 
@@ -24,7 +28,7 @@ type InterruptHandler func()
 func RegisterInterruptHandler(h InterruptHandler) {}
 
 // HandleInterrupts is a no-op on windows
-func HandleInterrupts() {}
+func HandleInterrupts(*zap.Logger) {}
 
 // Exit calls os.Exit
 func Exit(code int) {

pkg/osutil/osutil_test.go

@@ -21,6 +21,8 @@ import (
 	"syscall"
 	"testing"
 	"time"
+
+	"go.uber.org/zap"
 )
 
 func init() { setDflSignal = func(syscall.Signal) {} }
@@ -69,7 +71,7 @@ func TestHandleInterrupts(t *testing.T) {
 		c := make(chan os.Signal, 2)
 		signal.Notify(c, sig)
 
-		HandleInterrupts()
+		HandleInterrupts(zap.NewExample())
 		syscall.Kill(syscall.Getpid(), sig)
 
 		// we should receive the signal once from our own kill and