Prometheus add nodes gauge for SQS mode

cmd/node-termination-handler.go

@@ -120,7 +120,7 @@ func main() {
 		log.Fatal().Err(err).Msg("Unable to instantiate a node for various kubernetes node functions,")
 	}
 
-	metrics, err := observability.InitMetrics(nthConfig.EnablePrometheus, nthConfig.PrometheusPort)
+	metrics, err := observability.InitMetrics(nthConfig)
 	if err != nil {
 		nthConfig.Print()
 		log.Fatal().Err(err).Msg("Unable to instantiate observability metrics,")
@@ -215,6 +215,12 @@ func main() {
 		}
 		log.Debug().Msgf("AWS Credentials retrieved from provider: %s", creds.ProviderName)
 
+		ec2Client := ec2.New(sess)
+
+		if nthConfig.EnablePrometheus {
+			go metrics.InitNodeMetrics(node, ec2Client)
+		}
+
 		completeLifecycleActionDelay := time.Duration(nthConfig.CompleteLifecycleActionDelaySeconds) * time.Second
 		sqsMonitor := sqsevent.SQSMonitor{
 			CheckIfManaged:                nthConfig.CheckTagBeforeDraining,
@@ -224,7 +230,7 @@ func main() {
 			CancelChan:                    cancelChan,
 			SQS:                           sqsevent.GetSqsClient(sess),
 			ASG:                           autoscaling.New(sess),
-			EC2:                           ec2.New(sess),
+			EC2:                           ec2Client,
 			BeforeCompleteLifecycleAction: func() { <-time.After(completeLifecycleActionDelay) },
 		}
 		monitoringFns[sqsEvents] = sqsMonitor

pkg/ec2helper/ec2helper.go

@@ -0,0 +1,98 @@
+// Copyright 2016-2017 Amazon.com, Inc. or its affiliates. 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. A copy of the
+// License is located at
+//
+//     http://aws.amazon.com/apache2.0/
+//
+// or in the "license" file accompanying this file. This file 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 ec2helper
+
+import (
+	"fmt"
+
+	"github.com/aws/aws-sdk-go/aws"
+	"github.com/aws/aws-sdk-go/service/ec2"
+	"github.com/aws/aws-sdk-go/service/ec2/ec2iface"
+)
+
+type IEC2Helper interface {
+	GetInstanceIdsMapByTagKey(tag string) (map[string]bool, error)
+}
+
+type EC2Helper struct {
+	ec2ServiceClient ec2iface.EC2API
+}
+
+func New(ec2 ec2iface.EC2API) EC2Helper {
+	return EC2Helper{
+		ec2ServiceClient: ec2,
+	}
+}
+
+func (h EC2Helper) GetInstanceIdsByTagKey(tag string) ([]string, error) {
+	ids := []string{}
+	var nextToken string
+
+	for {
+		result, err := h.ec2ServiceClient.DescribeInstances(&ec2.DescribeInstancesInput{
+			Filters: []*ec2.Filter{
+				{
+					Name:   aws.String("tag-key"),
+					Values: []*string{aws.String(tag)},
+				},
+			},
+			NextToken: &nextToken,
+		})
+
+		if err != nil {
+			return nil, err
+		}
+
+		if result == nil || result.Reservations == nil {
+			return nil, fmt.Errorf("failed to describe instances")
+		}
+
+		for _, reservation := range result.Reservations {
+			if reservation.Instances == nil {
+				continue
+			}
+			for _, instance := range reservation.Instances {
+				if instance == nil || instance.InstanceId == nil {
+					continue
+				}
+				ids = append(ids, *instance.InstanceId)
+			}
+		}
+
+		if result.NextToken == nil {
+			break
+		}
+		nextToken = *result.NextToken
+	}
+
+	return ids, nil
+}
+
+func (h EC2Helper) GetInstanceIdsMapByTagKey(tag string) (map[string]bool, error) {
+	idMap := map[string]bool{}
+	ids, err := h.GetInstanceIdsByTagKey(tag)
+	if err != nil {
+		return nil, err
+	}
+
+	if ids == nil {
+		return nil, fmt.Errorf("failed to describe instances")
+	}
+
+	for _, id := range ids {
+		idMap[id] = true
+	}
+
+	return idMap, nil
+}

pkg/ec2helper/ec2helper_test.go

@@ -0,0 +1,74 @@
+// Copyright 2016-2017 Amazon.com, Inc. or its affiliates. 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. A copy of the
+// License is located at
+//
+//     http://aws.amazon.com/apache2.0/
+//
+// or in the "license" file accompanying this file. This file 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 ec2helper_test
+
+import (
+	"testing"
+
+	"github.com/aws/aws-node-termination-handler/pkg/ec2helper"
+	h "github.com/aws/aws-node-termination-handler/pkg/test"
+	"github.com/aws/aws-sdk-go/aws"
+	"github.com/aws/aws-sdk-go/service/ec2"
+)
+
+const (
+	instanceId1 = "i-1"
+	instanceId2 = "i-2"
+)
+
+func TestGetInstanceIdsByTagKey(t *testing.T) {
+	ec2Mock := h.MockedEC2{
+		DescribeInstancesResp: getDescribeInstancesResp(),
+	}
+	ec2Helper := ec2helper.New(ec2Mock)
+	instanceIds, err := ec2Helper.GetInstanceIdsByTagKey("myNTHManagedTag")
+	h.Ok(t, err)
+
+	h.Equals(t, 2, len(instanceIds))
+	h.Equals(t, instanceId1, instanceIds[0])
+	h.Equals(t, instanceId2, instanceIds[1])
+}
+
+func TestGetInstanceIdsMapByTagKey(t *testing.T) {
+	ec2Mock := h.MockedEC2{
+		DescribeInstancesResp: getDescribeInstancesResp(),
+	}
+	ec2Helper := ec2helper.New(ec2Mock)
+	instanceIdsMap, err := ec2Helper.GetInstanceIdsMapByTagKey("myNTHManagedTag")
+	h.Ok(t, err)
+
+	_, exist := instanceIdsMap[instanceId1]
+	h.Equals(t, true, exist)
+	_, exist = instanceIdsMap[instanceId2]
+	h.Equals(t, true, exist)
+	_, exist = instanceIdsMap["non-existent instance id"]
+	h.Equals(t, false, exist)
+}
+
+func getDescribeInstancesResp() ec2.DescribeInstancesOutput {
+	return ec2.DescribeInstancesOutput{
+		Reservations: []*ec2.Reservation{
+			{
+				Instances: []*ec2.Instance{
+					{
+						InstanceId: aws.String(instanceId1),
+					},
+					{
+						InstanceId: aws.String(instanceId2),
+					},
+				},
+			},
+		},
+	}
+}

pkg/node/node.go

@@ -17,6 +17,7 @@ import (
 	"context"
 	"encoding/json"
 	"fmt"
+	"regexp"
 	"strconv"
 	"strings"
 	"time"
@@ -74,6 +75,7 @@ const (
 var (
 	maxRetryDeadline      time.Duration = 5 * time.Second
 	conflictRetryInterval time.Duration = 750 * time.Millisecond
+	instanceIDRegex                     = regexp.MustCompile(`^i-.*`)
 )
 
 // Node represents a kubernetes node with functions to manipulate its state via the kubernetes api server
@@ -635,6 +637,41 @@ func (n Node) fetchKubernetesNode(nodeName string) (*corev1.Node, error) {
 	return &matchingNodes.Items[0], nil
 }
 
+// fetchKubernetesNode will send an http request to the k8s api server and return list of AWS EC2 instance id
+func (n Node) FetchKubernetesNodeInstanceIds() ([]string, error) {
+	ids := []string{}
+
+	if n.nthConfig.DryRun {
+		log.Info().Msgf("Would have retrieved nodes, but dry-run flag was set")
+		return ids, nil
+	}
+	matchingNodes, err := n.drainHelper.Client.CoreV1().Nodes().List(context.TODO(), metav1.ListOptions{})
+	if err != nil {
+		log.Warn().Msgf("Unable to list Nodes")
+		return nil, err
+	}
+
+	if matchingNodes == nil || matchingNodes.Items == nil {
+		return nil, fmt.Errorf("failed to list nodes")
+	}
+
+	for _, node := range matchingNodes.Items {
+		// sample providerID: aws:///us-west-2a/i-0abcd1234efgh5678
+		parts := strings.Split(node.Spec.ProviderID, "/")
+		if len(parts) < 2 {
+			log.Warn().Msgf("Found invalid providerID: %s", node.Spec.ProviderID)
+			continue
+		}
+
+		instanceId := parts[len(parts)-1]
+		if instanceIDRegex.MatchString(instanceId) {
+			ids = append(ids, parts[len(parts)-1])
+		}
+	}
+
+	return ids, nil
+}
+
 func (n Node) fetchAllPods(nodeName string) (*corev1.PodList, error) {
 	if n.nthConfig.DryRun {
 		log.Info().Msgf("Would have retrieved running pod list on node %s, but dry-run flag was set", nodeName)

pkg/node/node_test.go

@@ -15,6 +15,7 @@ package node_test
 
 import (
 	"context"
+	"fmt"
 	"strconv"
 	"strings"
 	"testing"
@@ -35,7 +36,11 @@ import (
 )
 
 // Size of the fakeRecorder buffer
-const recorderBufferSize = 10
+const (
+	recorderBufferSize = 10
+	instanceId1        = "i-0abcd1234efgh5678"
+	instanceId2        = "i-0wxyz5678ijkl1234"
+)
 
 var nodeName = "NAME"
 
@@ -379,6 +384,31 @@ func TestUncordonIfRebootedTimeParseFailure(t *testing.T) {
 	h.Assert(t, err != nil, "Failed to return error on UncordonIfReboted failure to parse time")
 }
 
+func TestFetchKubernetesNodeInstanceIds(t *testing.T) {
+	client := fake.NewSimpleClientset(
+		&v1.Node{
+			ObjectMeta: metav1.ObjectMeta{Name: "node-1"},
+			Spec:       v1.NodeSpec{ProviderID: fmt.Sprintf("aws:///us-west-2a/%s", instanceId1)},
+		},
+		&v1.Node{
+			ObjectMeta: metav1.ObjectMeta{Name: "node-2"},
+			Spec:       v1.NodeSpec{ProviderID: fmt.Sprintf("aws:///us-west-2a/%s", instanceId2)},
+		},
+	)
+
+	_, err := client.CoreV1().Nodes().List(context.Background(), metav1.ListOptions{})
+	h.Ok(t, err)
+
+	node, err := newNode(config.Config{}, client)
+	h.Ok(t, err)
+
+	instanceIds, err := node.FetchKubernetesNodeInstanceIds()
+	h.Ok(t, err)
+	h.Equals(t, 2, len(instanceIds))
+	h.Equals(t, instanceId1, instanceIds[0])
+	h.Equals(t, instanceId2, instanceIds[1])
+}
+
 func TestFilterOutDaemonSetPods(t *testing.T) {
 	tNode, err := newNode(config.Config{IgnoreDaemonSets: true}, fake.NewSimpleClientset())
 	h.Ok(t, err)