Add first version of node-problem-detector

pkg/kernelmonitor/translator/translator.go

@@ -0,0 +1,86 @@
+/*
+Copyright 2016 The Kubernetes Authors All rights reserved.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package translator
+
+import (
+	"fmt"
+	"strconv"
+	"strings"
+
+	"k8s.io/node-problem-detector/pkg/kernelmonitor/types"
+)
+
+// Translator translates a log line into types.KernelLog, so that kernel monitor
+// could parse it whatever the original format is.
+type Translator interface {
+	// Translate translates one log line into types.KernelLog.
+	Translate(string) (*types.KernelLog, error)
+}
+
+// defaultTranslator works well for ubuntu and debian, but may not work well with
+// other os distros. However it is easy to add a new translator for new os distro.
+type defaultTranslator struct{}
+
+// NewDefaultTranslator creates a default translator.
+func NewDefaultTranslator() Translator {
+	return &defaultTranslator{}
+}
+
+func (t *defaultTranslator) Translate(line string) (*types.KernelLog, error) {
+	timestr, message, err := parseLine(line)
+	if err != nil {
+		return nil, err
+	}
+	timestamp, err := parseTimestamp(timestr)
+	if err != nil {
+		return nil, err
+	}
+	return &types.KernelLog{
+		Timestamp: timestamp,
+		Message:   message,
+	}, nil
+}
+
+func parseLine(line string) (string, string, error) {
+	// Example line: Jan  1 00:00:00 hostname kernel: [0.000000] component: log message
+	timestampPrefix := "kernel: ["
+	timestampSuffix := "]"
+	idx := strings.Index(line, timestampPrefix)
+	if idx == -1 {
+		return "", "", fmt.Errorf("can't find timestamp prefix %q in line %q", timestampPrefix, line)
+	}
+	line = line[idx+len(timestampPrefix):]
+
+	idx = strings.Index(line, timestampSuffix)
+	if idx == -1 {
+		return "", "", fmt.Errorf("can't find timestamp suffix %q in line %q", timestampSuffix, line)
+	}
+
+	timestamp := strings.Trim(line[:idx], " ")
+	message := strings.Trim(line[idx+1:], " ")
+
+	return timestamp, message, nil
+}
+
+func parseTimestamp(timestamp string) (int64, error) {
+	f, err := strconv.ParseFloat(timestamp, 64)
+	if err != nil {
+		return 0, err
+	}
+	// seconds to microseconds
+	return int64(f * 1000000), nil
+}

pkg/kernelmonitor/translator/translator_test.go

@@ -0,0 +1,64 @@
+/*
+Copyright 2016 The Kubernetes Authors All rights reserved.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package translator
+
+import (
+	"testing"
+)
+
+func TestDefaultTranslator(t *testing.T) {
+	tr := NewDefaultTranslator()
+
+	testCases := []struct {
+		input     string
+		err       bool
+		timestamp int64
+		message   string
+	}{
+		{
+			input:     "Jan  1 00:00:00 hostname kernel: [9.999999] component: log message",
+			timestamp: 9999999,
+			message:   "component: log message",
+		},
+		{
+			input:     "Jan  1 00:00:00 hostname kernel: [9.999999]",
+			timestamp: 9999999,
+			message:   "",
+		},
+		{
+			input: "Jan  1 00:00:00 hostname kernel: [9.999999 component: log message",
+			err:   true,
+		},
+		{
+			input: "Jan  1 00:00:00 hostname user: [9.999999] component: log message",
+			err:   true,
+		},
+	}
+
+	for c, test := range testCases {
+		log, err := tr.Translate(test.input)
+		if test.err {
+			if err == nil {
+				t.Errorf("case %d: expect error should occur, got %+v, %v", c+1, log, err)
+			}
+			continue
+		}
+		if test.timestamp != log.Timestamp || test.message != log.Message {
+			t.Errorf("case %d: expect timestamp: %d, message: %q; got %+v", c+1, test.timestamp, test.message, log)
+		}
+	}
+}