Deriving podIps of the pods for k8s service if target pod has service…

…Mesh sidecar

Signed-off-by: Shubham Chaudhary <shubham.chaudhary@harness.io>

chaoslib/litmus/network-chaos/lib/network-chaos.go

@@ -2,6 +2,8 @@ package lib
 
 import (
 	"context"
+	"fmt"
+	k8serrors "k8s.io/apimachinery/pkg/api/errors"
 	"net"
 	"strconv"
 	"strings"
@@ -19,6 +21,8 @@ import (
 	v1 "k8s.io/apimachinery/pkg/apis/meta/v1"
 )
 
+var serviceMesh = []string{"istio", "envoy"}
+
 //PrepareAndInjectChaos contains the prepration & injection steps
 func PrepareAndInjectChaos(experimentsDetails *experimentTypes.ExperimentDetails, clients clients.ClientSets, resultDetails *types.ResultDetails, eventsDetails *types.EventDetails, chaosDetails *types.ChaosDetails, args string) error {
 
@@ -103,11 +107,6 @@ func PrepareAndInjectChaos(experimentsDetails *experimentTypes.ExperimentDetails
 		}
 	}
 
-	experimentsDetails.DestinationIPs, err = GetTargetIps(experimentsDetails.DestinationIPs, experimentsDetails.DestinationHosts)
-	if err != nil {
-		return err
-	}
-
 	if experimentsDetails.EngineName != "" {
 		if err := common.SetHelperData(chaosDetails, experimentsDetails.SetHelperData, clients); err != nil {
 			return err
@@ -146,6 +145,11 @@ func injectChaosInSerialMode(experimentsDetails *experimentTypes.ExperimentDetai
 	// creating the helper pod to perform network chaos
 	for _, pod := range targetPodList.Items {
 
+		experimentsDetails.DestinationIPs, err = GetTargetIps(experimentsDetails.DestinationIPs, experimentsDetails.DestinationHosts, clients, isServiceMeshEnabledForPod(pod))
+		if err != nil {
+			return err
+		}
+
 		//Get the target container name of the application pod
 		if !experimentsDetails.IsTargetContainerProvided {
 			experimentsDetails.TargetContainer, err = common.GetTargetContainer(experimentsDetails.AppNS, pod.Name, clients)
@@ -207,6 +211,11 @@ func injectChaosInParallelMode(experimentsDetails *experimentTypes.ExperimentDet
 	// creating the helper pod to perform network chaos
 	for _, pod := range targetPodList.Items {
 
+		experimentsDetails.DestinationIPs, err = GetTargetIps(experimentsDetails.DestinationIPs, experimentsDetails.DestinationHosts, clients, isServiceMeshEnabledForPod(pod))
+		if err != nil {
+			return err
+		}
+
 		//Get the target container name of the application pod
 		//It checks the empty target container for the first iteration only
 		if !experimentsDetails.IsTargetContainerProvided {
@@ -350,9 +359,9 @@ func getPodEnv(experimentsDetails *experimentTypes.ExperimentDetails, podName, a
 // GetTargetIps return the comma separated target ips
 // It fetch the ips from the target ips (if defined by users)
 // it append the ips from the host, if target host is provided
-func GetTargetIps(targetIPs, targetHosts string) (string, error) {
+func GetTargetIps(targetIPs, targetHosts string, clients clients.ClientSets, serviceMesh bool) (string, error) {
 
-	ipsFromHost, err := getIpsForTargetHosts(targetHosts)
+	ipsFromHost, err := getIpsForTargetHosts(targetHosts, clients, serviceMesh)
 	if err != nil {
 		return "", err
 	}
@@ -364,15 +373,51 @@ func GetTargetIps(targetIPs, targetHosts string) (string, error) {
 	return targetIPs, nil
 }
 
+// it derive the pod ips from the kubernetes service
+func getPodIPFromService(host string, clients clients.ClientSets) ([]string, error) {
+	var ips []string
+	svcFields := strings.Split(host, ".")
+	if len(svcFields) != 5 {
+		return ips, fmt.Errorf("provide the valid FQDN for service in '<svc-name>.<namespace>.svc.cluster.local format, host: %v", host)
+	}
+	svcName, svcNs := svcFields[0], svcFields[1]
+	svc, err := clients.KubeClient.CoreV1().Services(svcNs).Get(context.Background(), svcName, v1.GetOptions{})
+	if err != nil {
+		if k8serrors.IsForbidden(err) {
+			log.Warnf("forbidden - failed to get %v service in %v namespace, err: %v", svcName, svcNs, err)
+			return ips, nil
+		}
+		return ips, err
+	}
+	for k, v := range svc.Spec.Selector {
+		pods, err := clients.KubeClient.CoreV1().Pods(svcNs).List(context.Background(), v1.ListOptions{LabelSelector: fmt.Sprintf("%s=%s", k, v)})
+		if err != nil {
+			return ips, err
+		}
+		for _, p := range pods.Items {
+			ips = append(ips, p.Status.PodIP)
+		}
+	}
+	return ips, nil
+}
+
 // getIpsForTargetHosts resolves IP addresses for comma-separated list of target hosts and returns comma-separated ips
-func getIpsForTargetHosts(targetHosts string) (string, error) {
+func getIpsForTargetHosts(targetHosts string, clients clients.ClientSets, serviceMesh bool) (string, error) {
 	if targetHosts == "" {
 		return "", nil
 	}
 	hosts := strings.Split(targetHosts, ",")
 	finalHosts := ""
 	var commaSeparatedIPs []string
 	for i := range hosts {
+		if strings.Contains(hosts[i], "svc.cluster.local") && serviceMesh {
+			ips, err := getPodIPFromService(hosts[i], clients)
+			if err != nil {
+				return "", err
+			}
+			commaSeparatedIPs = append(commaSeparatedIPs, ips...)
+			continue
+		}
 		ips, err := net.LookupIP(hosts[i])
 		if err != nil {
 			log.Warnf("Unknown host: {%v}, it won't be included in the scope of chaos", hosts[i])
@@ -404,3 +449,13 @@ func SetChaosTunables(experimentsDetails *experimentTypes.ExperimentDetails) {
 	experimentsDetails.PodsAffectedPerc = common.ValidateRange(experimentsDetails.PodsAffectedPerc)
 	experimentsDetails.Sequence = common.GetRandomSequence(experimentsDetails.Sequence)
 }
+
+// It checks if pod contains service mesh sidecar
+func isServiceMeshEnabledForPod(pod apiv1.Pod) bool {
+	for _, c := range pod.Spec.Containers {
+		if common.StringExistsInSlice(c.Name, serviceMesh) {
+			return true
+		}
+	}
+	return false
+}

chaoslib/litmus/pod-network-partition/lib/network-policy.go

@@ -1,6 +1,7 @@
 package lib
 
 import (
+	"github.com/litmuschaos/litmus-go/pkg/clients"
 	"strings"
 
 	network_chaos "github.com/litmuschaos/litmus-go/chaoslib/litmus/network-chaos/lib"
@@ -179,7 +180,7 @@ func getPort(port int32, protocol corev1.Protocol) networkv1.NetworkPolicyPort {
 // for which traffic should be blocked
 func (np *NetworkPolicy) setExceptIPs(experimentsDetails *experimentTypes.ExperimentDetails) error {
 	// get all the target ips
-	destinationIPs, err := network_chaos.GetTargetIps(experimentsDetails.DestinationIPs, experimentsDetails.DestinationHosts)
+	destinationIPs, err := network_chaos.GetTargetIps(experimentsDetails.DestinationIPs, experimentsDetails.DestinationHosts, clients.ClientSets{}, false)
 	if err != nil {
 		return err
 	}

chaoslib/pumba/network-chaos/lib/network-chaos.go

@@ -289,7 +289,7 @@ func createHelperPod(experimentsDetails *experimentTypes.ExperimentDetails, clie
 // AddTargetIpsArgs inserts a comma-separated list of targetIPs (if provided by the user) into the pumba command/args
 func AddTargetIpsArgs(targetIPs, targetHosts string, args []string) ([]string, error) {
 
-	targetIPs, err := network_chaos.GetTargetIps(targetIPs, targetHosts)
+	targetIPs, err := network_chaos.GetTargetIps(targetIPs, targetHosts, clients.ClientSets{}, false)
 	if err != nil {
 		return nil, err
 	}

pkg/utils/common/common.go

@@ -212,3 +212,13 @@ func getRandomValue(a, b int) int {
 	rand.Seed(time.Now().Unix())
 	return (a + rand.Intn(b-a+1))
 }
+
+// StringExistsInSlice checks the existence of element in slice
+func StringExistsInSlice(val string, slice []string) bool {
+	for _, v := range slice {
+		if strings.Contains(val, v) {
+			return true
+		}
+	}
+	return false
+}