feat: add interval event emitting of CNS config snapshot

Author: jackieluc

cns/logger/constants.go

@@ -7,12 +7,14 @@ const (
 	ConfigSnapshotMetricsStr = "ConfigSnapshot"
 
 	// Dimensions
-	OrchestratorTypeStr = "OrchestratorType"
-	NodeIDStr           = "NodeID"
-	HomeAZStr           = "HomeAZ"
-	IsAZRSupportedStr   = "IsAZRSupported"
-	HomeAZErrorCodeStr  = "HomeAZErrorCode"
-	HomeAZErrorMsgStr   = "HomeAZErrorMsg"
+	OrchestratorTypeStr             = "OrchestratorType"
+	NodeIDStr                       = "NodeID"
+	HomeAZStr                       = "HomeAZ"
+	IsAZRSupportedStr               = "IsAZRSupported"
+	HomeAZErrorCodeStr              = "HomeAZErrorCode"
+	HomeAZErrorMsgStr               = "HomeAZErrorMsg"
+	CNSConfigPropertyStr            = "CNSConfiguration"
+	CNSConfigMD5CheckSumPropertyStr = "CNSConfigurationMD5Checksum"
 
 	// CNS NC Snspshot properties
 	CnsNCSnapshotEventStr         = "CNSNCSnapshot"

cns/metric/configsnapshot.go

@@ -0,0 +1,57 @@
+// Copyright 2018 Microsoft. All rights reserved.
+// MIT License
+
+package metric
+
+import (
+	"context"
+	"crypto/md5" //nolint:gosec // used for checksum
+	"encoding/json"
+	"time"
+
+	"github.com/Azure/azure-container-networking/aitelemetry"
+	"github.com/Azure/azure-container-networking/cns/configuration"
+	"github.com/Azure/azure-container-networking/cns/logger"
+)
+
+// SendCNSConfigSnapshot emits CNS config periodically
+func SendCNSConfigSnapshot(ctx context.Context, config *configuration.CNSConfig) {
+	ticker := time.NewTicker(time.Minute * time.Duration(config.TelemetrySettings.ConfigSnapshotIntervalInMins))
+	defer ticker.Stop()
+
+	event, err := createCNSConfigSnapshotEvent(config)
+	if err != nil {
+		logger.Errorf("[Azure CNS] SendCNSConfigSnapshot failed to create event at an interval: %v", err)
+		return
+	}
+
+	for {
+		select {
+		case <-ctx.Done():
+			return
+		case <-ticker.C:
+			logger.LogEvent(event)
+		}
+	}
+}
+
+func createCNSConfigSnapshotEvent(config *configuration.CNSConfig) (aitelemetry.Event, error) {
+	bb, err := json.Marshal(config) //nolint:musttag // no tag needed for config
+	if err != nil {
+		return aitelemetry.Event{}, err
+	}
+
+	cs := md5.Sum(bb) //nolint:gosec // used for checksum
+	csStr := string(cs[:])
+
+	event := aitelemetry.Event{
+		EventName:  logger.ConfigSnapshotMetricsStr,
+		ResourceID: csStr, // not guaranteed unique, instead use VM ID and Subscription to correlate
+		Properties: map[string]string{
+			logger.CNSConfigPropertyStr:            string(bb),
+			logger.CNSConfigMD5CheckSumPropertyStr: csStr,
+		},
+	}
+
+	return event, nil
+}

cns/metric/configsnapshot_test.go

@@ -0,0 +1,40 @@
+package metric
+
+import (
+	"crypto/md5"
+	"encoding/json"
+	"testing"
+
+	"github.com/Azure/azure-container-networking/aitelemetry"
+	"github.com/Azure/azure-container-networking/cns/configuration"
+	"github.com/Azure/azure-container-networking/cns/logger"
+	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
+)
+
+func TestCreateCNSConfigSnapshotEvent(t *testing.T) {
+	logger.InitLogger("testlogs", 0, 0, "./")
+
+	config, err := configuration.ReadConfig("../configuration/testdata/good.json")
+	require.NoError(t, err)
+
+	event, err := createCNSConfigSnapshotEvent(config)
+	require.NoError(t, err)
+
+	bb, err := json.Marshal(config)
+	require.NoError(t, err)
+
+	cs := md5.Sum(bb)
+	csStr := string(cs[:])
+
+	expected := aitelemetry.Event{
+		EventName:  logger.ConfigSnapshotMetricsStr,
+		ResourceID: csStr,
+		Properties: map[string]string{
+			logger.CNSConfigPropertyStr:            string(bb),
+			logger.CNSConfigMD5CheckSumPropertyStr: csStr,
+		},
+	}
+
+	assert.Equal(t, expected, event)
+}

cns/service/main.go

@@ -578,6 +578,8 @@ func main() {
 		} else {
 			logger.InitAI(aiConfig, ts.DisableTrace, ts.DisableMetric, ts.DisableEvent)
 		}
+
+		go metric.SendCNSConfigSnapshot(rootCtx, cnsconfig)
 	}
 	logger.Printf("[Azure CNS] Using config: %+v", cnsconfig)