fix comments

Author: paulyufan2

cns/middlewares/k8sSwiftV2.go

@@ -238,8 +238,8 @@ func (k *K8sSWIFTv2Middleware) AddRoutes(cidrs []string, gatewayIP string) []cns
 	return routes
 }
 
-// CNS gets node and service CIDRs from configuration env and parse them to get the v4 and v6 IPs
-func (k *K8sSWIFTv2Middleware) GetCidrs() (v4IPs, v6IPs []string, err error) {
+// Both Linux and Windows CNS gets infravnet and service CIDRs from configuration env
+func (k *K8sSWIFTv2Middleware) GetCidrs() ([]string, []string, error) {
 	v4Cidrs := []string{}
 	v6Cidrs := []string{}
 

cns/middlewares/k8sSwiftV2_linux.go

@@ -32,7 +32,7 @@ func (k *K8sSWIFTv2Middleware) setRoutes(podIPInfo *cns.PodIpInfo) error {
 		routes = append(routes, virtualGWRoute, route)
 
 	case cns.InfraNIC:
-		// get service and infravnet routes
+		// Linux CNS middleware sets the infra routes(infravnet/pod/service cidrs) to infraNIC interface for the podIPInfo used in SWIFT V2 Linux scenario
 		infraRoutes, err := k.getInfraRoutes(podIPInfo)
 		if err != nil {
 			return errors.Wrap(err, "failed to get infra routes for infraNIC interface")
@@ -50,9 +50,10 @@ func (k *K8sSWIFTv2Middleware) setRoutes(podIPInfo *cns.PodIpInfo) error {
 	return nil
 }
 
-// CNS gets pod CIDRs from configuration env and parse them to get the v4 and v6 IPs
-// Containerd reassigns the IP to the adapter and kernel configures the pod cidr route by default, so windows swiftv2 does not require pod cidr
-func (k *K8sSWIFTv2Middleware) GetPodCidrs() (v4IPs, v6IPs []string, err error) {
+// Linux CNS gets pod CIDRs from configuration env
+// Containerd reassigns the IP to the adapter and kernel configures the pod cidr route by default on Windows VM
+// Hence the windows swiftv2 scenario does not require pod cidr
+func (k *K8sSWIFTv2Middleware) GetPodCidrs() ([]string, []string, error) {
 	v4PodCidrs := []string{}
 	v6PodCidrs := []string{}
 
@@ -72,6 +73,8 @@ func (k *K8sSWIFTv2Middleware) GetPodCidrs() (v4IPs, v6IPs []string, err error)
 	return v4PodCidrs, v6PodCidrs, nil
 }
 
+// getInfraRoutes() returns the infra routes including infravnet/pod/service cidrs for the podIPInfo used in SWIFT V2 Linux scenario
+// Linux uses 169.254.1.1 as the default ipv4 gateway and fe80::1234:5678:9abc as the default ipv6 gateway
 func (k *K8sSWIFTv2Middleware) getInfraRoutes(podIPInfo *cns.PodIpInfo) ([]cns.Route, error) {
 	var routes []cns.Route
 
@@ -93,7 +96,6 @@ func (k *K8sSWIFTv2Middleware) getInfraRoutes(podIPInfo *cns.PodIpInfo) ([]cns.R
 	v4IPs = append(v4IPs, v4PodIPs...)
 	v6IPs = append(v6IPs, v6PodIPs...)
 
-	// Linux uses 169.254.1.1 as the default ipv4 gateway and fe80::1234:5678:9abc as the default ipv6 gateway
 	if ip.Is4() {
 		routes = append(routes, k.AddRoutes(v4IPs, overlayGatewayv4)...)
 	} else {

cns/middlewares/k8sSwiftV2_linux_test.go

@@ -3,7 +3,6 @@ package middlewares
 import (
 	"context"
 	"fmt"
-	"reflect"
 	"testing"
 
 	"github.com/Azure/azure-container-networking/cns"
@@ -12,6 +11,7 @@ import (
 	"github.com/Azure/azure-container-networking/cns/middlewares/mock"
 	"github.com/Azure/azure-container-networking/cns/types"
 	"github.com/Azure/azure-container-networking/crd/multitenancy/api/v1alpha1"
+	"github.com/google/go-cmp/cmp"
 	"gotest.tools/v3/assert"
 )
 
@@ -346,7 +346,7 @@ func TestSetRoutesSuccess(t *testing.T) {
 	}
 
 	for i := range podIPInfo {
-		reflect.DeepEqual(podIPInfo[i].Routes, desiredPodIPInfo[i].Routes)
+		cmp.Equal(podIPInfo[i].Routes, desiredPodIPInfo[i].Routes)
 	}
 }
 

cns/middlewares/k8sSwiftV2_windows.go

@@ -36,7 +36,7 @@ func (k *K8sSWIFTv2Middleware) setRoutes(podIPInfo *cns.PodIpInfo) error {
 		}
 		podIPInfo.Routes = append(podIPInfo.Routes, route)
 
-		// set routes(infravnet and service cidrs) for infraNIC interface
+		// // Linux CNS middleware sets the infra routes(infravnet and service cidrs) to infraNIC interface for the podIPInfo used in SWIFT V2 Windows scenario
 		infraRoutes, err := k.getInfraRoutes(podIPInfo)
 		if err != nil {
 			return errors.Wrap(err, "failed to set routes for infraNIC interface")
@@ -220,6 +220,9 @@ func GetDefaultDenyBool(mtpnc v1alpha1.MultitenantPodNetworkConfig) bool {
 	return mtpnc.Status.DefaultDenyACL
 }
 
+// getInfraRoutes() returns the infra routes including infravnet/ and service cidrs for the podIPInfo used in SWIFT V2 Windows scenario
+// Windows uses default route 0.0.0.0 as the gateway IP for containerd to configure;
+// For example, containerd would set route like: ip route 10.0.0.0/16 via 0.0.0.0 dev eth0
 func (k *K8sSWIFTv2Middleware) getInfraRoutes(podIPInfo *cns.PodIpInfo) ([]cns.Route, error) {
 	var routes []cns.Route
 
@@ -228,16 +231,13 @@ func (k *K8sSWIFTv2Middleware) getInfraRoutes(podIPInfo *cns.PodIpInfo) ([]cns.R
 		return nil, errors.Wrapf(err, "failed to parse podIPConfig IP address %s", podIPInfo.PodIPConfig.IPAddress)
 	}
 
-	// swiftv2 windows does not support ipv6
+	// TODO: add ipv6 when supported
 	v4IPs, _, err := k.GetCidrs()
 	if err != nil {
 		return nil, errors.Wrap(err, "failed to get CIDRs")
 	}
 
 	if ip.Is4() {
-		// add routes to podIPInfo for the given CIDRs and gateway IP
-		// always use default gateway IP for containerd to configure routes;
-		// containerd will set route with default gateway ip like 10.0.0.0/16 via 0.0.0.0 dev eth0
 		routes = append(routes, k.AddRoutes(v4IPs, defaultGateway)...)
 	}
 

cns/middlewares/k8sSwiftV2_windows_test.go

@@ -20,6 +20,7 @@ func TestSetRoutesSuccess(t *testing.T) {
 	middleware := K8sSWIFTv2Middleware{Cli: mock.NewClient()}
 	t.Setenv(configuration.EnvServiceCIDRs, "10.0.0.0/16")
 	t.Setenv(configuration.EnvInfraVNETCIDRs, "10.240.0.10/16")
+	t.Setenv(configuration.EnvPodCIDRs, "10.1.0.10/24") // make sure windows swiftv2 does not set pod cidr route
 
 	podIPInfo := []cns.PodIpInfo{
 		{