From a986976a1d8716ba36ba301c3e0043e051b06b43 Mon Sep 17 00:00:00 2001
From: Random-Liu <lantaol@google.com>
Date: Fri, 27 Jan 2017 13:30:10 -0800
Subject: [PATCH] Only change transition timestamp when condition is changed.

---
 pkg/kernelmonitor/kernel_monitor.go      |  9 ++++++--
 pkg/kernelmonitor/kernel_monitor_test.go | 29 +++++++++++++++++++++---
 2 files changed, 33 insertions(+), 5 deletions(-)

diff --git a/pkg/kernelmonitor/kernel_monitor.go b/pkg/kernelmonitor/kernel_monitor.go
index 3092c476..60ec9e6b 100644
--- a/pkg/kernelmonitor/kernel_monitor.go
+++ b/pkg/kernelmonitor/kernel_monitor.go
@@ -161,10 +161,15 @@ func (k *kernelMonitor) generateStatus(logs []*kerntypes.KernelLog, rule kerntyp
 			condition := &k.conditions[i]
 			if condition.Type == rule.Condition {
 				condition.Type = rule.Condition
+				// Update transition timestamp and message when the condition
+				// changes. Condition is considered to be changed only when
+				// status or reason changes.
+				if !condition.Status || condition.Reason != rule.Reason {
+					condition.Transition = timestamp
+					condition.Message = message
+				}
 				condition.Status = true
-				condition.Transition = timestamp
 				condition.Reason = rule.Reason
-				condition.Message = message
 				break
 			}
 		}
diff --git a/pkg/kernelmonitor/kernel_monitor_test.go b/pkg/kernelmonitor/kernel_monitor_test.go
index 26dc1856..8d84f297 100644
--- a/pkg/kernelmonitor/kernel_monitor_test.go
+++ b/pkg/kernelmonitor/kernel_monitor_test.go
@@ -36,12 +36,13 @@ func TestGenerateStatus(t *testing.T) {
 		{
 			Type:       testConditionA,
 			Status:     true,
-			Transition: time.Now(),
+			Transition: time.Unix(500, 500),
+			Reason:     "initial reason",
 		},
 		{
 			Type:       testConditionB,
 			Status:     false,
-			Transition: time.Now(),
+			Transition: time.Unix(500, 500),
 		},
 	}
 	logs := []*kerntypes.KernelLog{
@@ -79,6 +80,26 @@ func TestGenerateStatus(t *testing.T) {
 				},
 			},
 		},
+		// Should not update transition time when status and reason are not changed.
+		{
+			rule: kerntypes.Rule{
+				Type:      kerntypes.Perm,
+				Condition: testConditionA,
+				Reason:    "initial reason",
+			},
+			expected: types.Status{
+				Source: testSource,
+				Conditions: []types.Condition{
+					{
+						Type:       testConditionA,
+						Status:     true,
+						Transition: time.Unix(500, 500),
+						Reason:     "initial reason",
+					},
+					initConditions[1],
+				},
+			},
+		},
 		{
 			rule: kerntypes.Rule{
 				Type:   kerntypes.Temp,
@@ -100,7 +121,9 @@ func TestGenerateStatus(t *testing.T) {
 			config: MonitorConfig{
 				Source: testSource,
 			},
-			conditions: initConditions,
+			// Copy the init conditions to make sure it's not changed
+			// during the test.
+			conditions: append([]types.Condition{}, initConditions...),
 		}
 		got := k.generateStatus(logs, test.rule)
 		if !reflect.DeepEqual(&test.expected, got) {