Merge pull request #112 from Random-Liu/cleanup-kmsg-log-watcher

Cleanup kmsg log watcher

Author: dchen1107

pkg/systemlogmonitor/README.md

@@ -47,7 +47,7 @@ System log monitor supports different log management tools with different log
 watchers:
 * [filelog](./logwatchers/filelog): Log watcher for
 arbitrary file based log.
-* [journald](.//logwatchers/journald): Log watcher for
+* [journald](.//logwatchers/journald): Log watcher for journald.
 * [kmsg](./logwatchers/kmsg): Log watcher for the kernel ring buffer device, /dev/kmsg.
 Set `plugin` in the configuration file to specify log watcher.
 
@@ -67,7 +67,7 @@ Log watcher specific configurations are configured in `pluginConfig`.
   * timestampFormat: The format of the timestamp. The format string is the time
     `2006-01-02T15:04:05Z07:00` in the expected format. (See
     [golang timestamp format](https://golang.org/pkg/time/#pkg-constants))
-* **kmsg**
+* **kmsg**: No configuration for now.
 
 ### Change Log Path
 

pkg/systemlogmonitor/logwatchers/kmsg/log_watcher.go

@@ -17,7 +17,6 @@ limitations under the License.
 package kmsg
 
 import (
-	"bufio"
 	"fmt"
 	"strings"
 	"time"
@@ -32,18 +31,16 @@ import (
 )
 
 type kernelLogWatcher struct {
-	cfg    types.WatcherConfig
-	logCh  chan *logtypes.Log
-	tomb   *util.Tomb
-	reader *bufio.Reader
+	cfg   types.WatcherConfig
+	logCh chan *logtypes.Log
+	tomb  *util.Tomb
 
 	kmsgParser kmsgparser.Parser
 	clock      utilclock.Clock
 }
 
 // NewKmsgWatcher creates a watcher which will read messages from /dev/kmsg
 func NewKmsgWatcher(cfg types.WatcherConfig) types.LogWatcher {
-	kmsgparser.NewParser()
 	return &kernelLogWatcher{
 		cfg:  cfg,
 		tomb: util.NewTomb(),
@@ -92,7 +89,9 @@ func (k *kernelLogWatcher) watchLoop(lookback time.Duration) {
 		select {
 		case <-k.tomb.Stopping():
 			glog.Infof("Stop watching kernel log")
-			k.kmsgParser.Close()
+			if err := k.kmsgParser.Close(); err != nil {
+				glog.Errorf("Failed to close kmsg parser: %v", err)
+			}
 			return
 		case msg := <-kmsgs:
 			glog.V(5).Infof("got kernel message: %+v", msg)
@@ -102,7 +101,7 @@ func (k *kernelLogWatcher) watchLoop(lookback time.Duration) {
 
 			// Discard too old messages
 			if k.clock.Since(msg.Timestamp) > lookback {
-				glog.V(5).Infof("throwing away msg %v for being too old: %v > %v", msg.Message, msg.Timestamp.String(), lookback.String())
+				glog.V(5).Infof("Throwing away msg %v for being too old: %v > %v", msg.Message, msg.Timestamp.String(), lookback.String())
 				continue
 			}
 

pkg/systemlogmonitor/logwatchers/kmsg/log_watcher_test.go

@@ -17,7 +17,6 @@ limitations under the License.
 package kmsg
 
 import (
-	"io"
 	"testing"
 
 	"code.cloudfoundry.org/clock/fakeclock"
@@ -140,21 +139,3 @@ func TestWatch(t *testing.T) {
 		}
 	}
 }
-
-type fakeKmsgReader struct {
-	logLines []string
-}
-
-func (r *fakeKmsgReader) Read(data []byte) (int, error) {
-	if len(r.logLines) == 0 {
-		return 0, io.EOF
-	}
-	l := r.logLines[0]
-	r.logLines = r.logLines[1:]
-	copy(data, []byte(l))
-	return len(l), nil
-}
-
-func (r *fakeKmsgReader) Close() error {
-	return nil
-}