Merge pull request #55265 from MrHohn/kubelet-network-codes-move

Automatic merge from submit-queue (batch tested with PRs 55265, 54092, 55353, 53733, 55385). If you want to cherry-pick this change to another branch, please follow the instructions <a href="https://github.com/kubernetes/community/blob/master/contributors/devel/cherry-picks.md">here</a>.

Rearrange kubelet networking codes

**What this PR does / why we need it**:
kubelet package contains multiple `*network.go` files, also some of the networking related codes scatter in different places. This PR rearranges the networking codes into `kubelet_network.go`. There is no functional changes.

**Which issue(s) this PR fixes** *(optional, in `fixes #<issue number>(, fixes #<issue_number>, ...)` format, will close the issue(s) when PR gets merged)*:
Fixes #55451 

**Special notes for your reviewer**:

**Release note**:

```release-note
NONE
```

pkg/kubelet/BUILD

@@ -18,7 +18,6 @@ go_library(
         "kubelet_pods.go",
         "kubelet_resources.go",
         "kubelet_volumes.go",
-        "networks.go",
         "oom_watcher.go",
         "pod_container_deletor.go",
         "pod_workers.go",
@@ -153,7 +152,6 @@ go_test(
         "kubelet_resources_test.go",
         "kubelet_test.go",
         "kubelet_volumes_test.go",
-        "networks_test.go",
         "oom_watcher_test.go",
         "pod_container_deletor_test.go",
         "pod_workers_test.go",

pkg/kubelet/kubelet.go

@@ -19,13 +19,11 @@ package kubelet
 import (
 	"crypto/tls"
 	"fmt"
-	"io/ioutil"
 	"net"
 	"net/http"
 	"net/url"
 	"os"
 	"path"
-	"path/filepath"
 	goruntime "runtime"
 	"sort"
 	"strings"
@@ -1401,64 +1399,6 @@ func (kl *Kubelet) GetKubeClient() clientset.Interface {
 	return kl.kubeClient
 }
 
-// GetClusterDNS returns a list of the DNS servers, a list of the DNS search
-// domains of the cluster, and a list of resolv.conf options.
-func (kl *Kubelet) GetClusterDNS(pod *v1.Pod) ([]string, []string, []string, bool, error) {
-	var hostDNS, hostSearch, hostOptions []string
-	// Get host DNS settings
-	if kl.resolverConfig != "" {
-		f, err := os.Open(kl.resolverConfig)
-		if err != nil {
-			return nil, nil, nil, false, err
-		}
-		defer f.Close()
-
-		hostDNS, hostSearch, hostOptions, err = kl.parseResolvConf(f)
-		if err != nil {
-			return nil, nil, nil, false, err
-		}
-	}
-	useClusterFirstPolicy := ((pod.Spec.DNSPolicy == v1.DNSClusterFirst && !kubecontainer.IsHostNetworkPod(pod)) || pod.Spec.DNSPolicy == v1.DNSClusterFirstWithHostNet)
-	if useClusterFirstPolicy && len(kl.clusterDNS) == 0 {
-		// clusterDNS is not known.
-		// pod with ClusterDNSFirst Policy cannot be created
-		kl.recorder.Eventf(pod, v1.EventTypeWarning, "MissingClusterDNS", "kubelet does not have ClusterDNS IP configured and cannot create Pod using %q policy. Falling back to DNSDefault policy.", pod.Spec.DNSPolicy)
-		log := fmt.Sprintf("kubelet does not have ClusterDNS IP configured and cannot create Pod using %q policy. pod: %q. Falling back to DNSDefault policy.", pod.Spec.DNSPolicy, format.Pod(pod))
-		kl.recorder.Eventf(kl.nodeRef, v1.EventTypeWarning, "MissingClusterDNS", log)
-
-		// fallback to DNSDefault
-		useClusterFirstPolicy = false
-	}
-
-	if !useClusterFirstPolicy {
-		// When the kubelet --resolv-conf flag is set to the empty string, use
-		// DNS settings that override the docker default (which is to use
-		// /etc/resolv.conf) and effectively disable DNS lookups. According to
-		// the bind documentation, the behavior of the DNS client library when
-		// "nameservers" are not specified is to "use the nameserver on the
-		// local machine". A nameserver setting of localhost is equivalent to
-		// this documented behavior.
-		if kl.resolverConfig == "" {
-			hostDNS = []string{"127.0.0.1"}
-			hostSearch = []string{"."}
-		} else {
-			hostSearch = kl.formDNSSearchForDNSDefault(hostSearch, pod)
-		}
-		return hostDNS, hostSearch, hostOptions, useClusterFirstPolicy, nil
-	}
-
-	// for a pod with DNSClusterFirst policy, the cluster DNS server is the only nameserver configured for
-	// the pod. The cluster DNS server itself will forward queries to other nameservers that is configured to use,
-	// in case the cluster DNS server cannot resolve the DNS query itself
-	dns := make([]string, len(kl.clusterDNS))
-	for i, ip := range kl.clusterDNS {
-		dns[i] = ip.String()
-	}
-	dnsSearch := kl.formDNSSearch(hostSearch, pod)
-
-	return dns, dnsSearch, hostOptions, useClusterFirstPolicy, nil
-}
-
 // syncPod is the transaction script for the sync of a single pod.
 //
 // Arguments:
@@ -2224,36 +2164,6 @@ func (kl *Kubelet) cleanUpContainersInPod(podID types.UID, exitedContainerID str
 	}
 }
 
-// Replace the nameserver in containerized-mounter's rootfs/etc/resolve.conf with kubelet.ClusterDNS
-func (kl *Kubelet) setupDNSinContainerizedMounter(mounterPath string) {
-	resolvePath := filepath.Join(strings.TrimSuffix(mounterPath, "/mounter"), "rootfs", "etc", "resolv.conf")
-	dnsString := ""
-	for _, dns := range kl.clusterDNS {
-		dnsString = dnsString + fmt.Sprintf("nameserver %s\n", dns)
-	}
-	if kl.resolverConfig != "" {
-		f, err := os.Open(kl.resolverConfig)
-		defer f.Close()
-		if err != nil {
-			glog.Error("Could not open resolverConf file")
-		} else {
-			_, hostSearch, _, err := kl.parseResolvConf(f)
-			if err != nil {
-				glog.Errorf("Error for parsing the reslov.conf file: %v", err)
-			} else {
-				dnsString = dnsString + "search"
-				for _, search := range hostSearch {
-					dnsString = dnsString + fmt.Sprintf(" %s", search)
-				}
-				dnsString = dnsString + "\n"
-			}
-		}
-	}
-	if err := ioutil.WriteFile(resolvePath, []byte(dnsString), 0600); err != nil {
-		glog.Errorf("Could not write dns nameserver in file %s, with error %v", resolvePath, err)
-	}
-}
-
 // isSyncPodWorthy filters out events that are not worthy of pod syncing
 func isSyncPodWorthy(event *pleg.PodLifecycleEvent) bool {
 	// ContatnerRemoved doesn't affect pod state

pkg/kubelet/kubelet_network.go

@@ -21,13 +21,17 @@ import (
 	"io"
 	"io/ioutil"
 	"os"
+	"path/filepath"
 	"strings"
 
 	"github.com/golang/glog"
 	"k8s.io/api/core/v1"
+	clientset "k8s.io/client-go/kubernetes"
 	"k8s.io/kubernetes/pkg/kubelet/apis/kubeletconfig"
+	kubecontainer "k8s.io/kubernetes/pkg/kubelet/container"
 	"k8s.io/kubernetes/pkg/kubelet/network"
 	kubetypes "k8s.io/kubernetes/pkg/kubelet/types"
+	"k8s.io/kubernetes/pkg/kubelet/util/format"
 	utiliptables "k8s.io/kubernetes/pkg/util/iptables"
 )
 
@@ -46,6 +50,77 @@ const (
 	KubeFirewallChain utiliptables.Chain = "KUBE-FIREWALL"
 )
 
+// This just exports required functions from kubelet proper, for use by network
+// plugins.
+// TODO(#35457): get rid of this backchannel to the kubelet. The scope of
+// the back channel is restricted to host-ports/testing, and restricted
+// to kubenet. No other network plugin wrapper needs it. Other plugins
+// only require a way to access namespace information, which they can do
+// directly through the methods implemented by criNetworkHost.
+type networkHost struct {
+	kubelet *Kubelet
+}
+
+func (nh *networkHost) GetPodByName(name, namespace string) (*v1.Pod, bool) {
+	return nh.kubelet.GetPodByName(name, namespace)
+}
+
+func (nh *networkHost) GetKubeClient() clientset.Interface {
+	return nh.kubelet.kubeClient
+}
+
+func (nh *networkHost) GetRuntime() kubecontainer.Runtime {
+	return nh.kubelet.GetRuntime()
+}
+
+func (nh *networkHost) SupportsLegacyFeatures() bool {
+	return true
+}
+
+// criNetworkHost implements the part of network.Host required by the
+// cri (NamespaceGetter). It leechs off networkHost for all other
+// methods, because networkHost is slated for deletion.
+type criNetworkHost struct {
+	*networkHost
+	// criNetworkHost currently support legacy features. Hence no need to support PortMappingGetter
+	*network.NoopPortMappingGetter
+}
+
+// GetNetNS returns the network namespace of the given containerID.
+// This method satisfies the network.NamespaceGetter interface for
+// networkHost. It's only meant to be used from network plugins
+// that are directly invoked by the kubelet (aka: legacy, pre-cri).
+// Any network plugin invoked by a cri must implement NamespaceGetter
+// to talk directly to the runtime instead.
+func (c *criNetworkHost) GetNetNS(containerID string) (string, error) {
+	return c.kubelet.GetRuntime().GetNetNS(kubecontainer.ContainerID{Type: "", ID: containerID})
+}
+
+// NoOpLegacyHost implements the network.LegacyHost interface for the remote
+// runtime shim by just returning empties. It doesn't support legacy features
+// like host port and bandwidth shaping.
+type NoOpLegacyHost struct{}
+
+// GetPodByName always returns "nil, true" for 'NoOpLegacyHost'
+func (n *NoOpLegacyHost) GetPodByName(namespace, name string) (*v1.Pod, bool) {
+	return nil, true
+}
+
+// GetKubeClient always returns "nil" for 'NoOpLegacyHost'
+func (n *NoOpLegacyHost) GetKubeClient() clientset.Interface {
+	return nil
+}
+
+// GetRuntime always returns "nil" for 'NoOpLegacyHost'
+func (n *NoOpLegacyHost) GetRuntime() kubecontainer.Runtime {
+	return nil
+}
+
+// SupportsLegacyFeatures always returns "false" for 'NoOpLegacyHost'
+func (n *NoOpLegacyHost) SupportsLegacyFeatures() bool {
+	return false
+}
+
 // effectiveHairpinMode determines the effective hairpin mode given the
 // configured mode, container runtime, and whether cbr0 should be configured.
 func effectiveHairpinMode(hairpinMode kubeletconfig.HairpinMode, containerRuntime string, networkPlugin string) (kubeletconfig.HairpinMode, error) {
@@ -89,7 +164,7 @@ func (kl *Kubelet) providerRequiresNetworkingConfiguration() bool {
 	return supported
 }
 
-func omitDuplicates(kl *Kubelet, pod *v1.Pod, combinedSearch []string) []string {
+func omitDuplicates(pod *v1.Pod, combinedSearch []string) []string {
 	uniqueDomains := map[string]bool{}
 
 	for _, dnsDomain := range combinedSearch {
@@ -101,7 +176,7 @@ func omitDuplicates(kl *Kubelet, pod *v1.Pod, combinedSearch []string) []string
 	return combinedSearch[:len(uniqueDomains)]
 }
 
-func formDNSSearchFitsLimits(kl *Kubelet, pod *v1.Pod, composedSearch []string) []string {
+func (kl *Kubelet) formDNSSearchFitsLimits(pod *v1.Pod, composedSearch []string) []string {
 	// resolver file Search line current limitations
 	resolvSearchLineDNSDomainsLimit := 6
 	resolvSearchLineLenLimit := 255
@@ -137,12 +212,12 @@ func formDNSSearchFitsLimits(kl *Kubelet, pod *v1.Pod, composedSearch []string)
 }
 
 func (kl *Kubelet) formDNSSearchForDNSDefault(hostSearch []string, pod *v1.Pod) []string {
-	return formDNSSearchFitsLimits(kl, pod, hostSearch)
+	return kl.formDNSSearchFitsLimits(pod, hostSearch)
 }
 
 func (kl *Kubelet) formDNSSearch(hostSearch []string, pod *v1.Pod) []string {
 	if kl.clusterDomain == "" {
-		formDNSSearchFitsLimits(kl, pod, hostSearch)
+		kl.formDNSSearchFitsLimits(pod, hostSearch)
 		return hostSearch
 	}
 
@@ -152,8 +227,8 @@ func (kl *Kubelet) formDNSSearch(hostSearch []string, pod *v1.Pod) []string {
 
 	combinedSearch := append(dnsSearch, hostSearch...)
 
-	combinedSearch = omitDuplicates(kl, pod, combinedSearch)
+	combinedSearch = omitDuplicates(pod, combinedSearch)
-	return formDNSSearchFitsLimits(kl, pod, combinedSearch)
+	return kl.formDNSSearchFitsLimits(pod, combinedSearch)
 }
 
 func (kl *Kubelet) checkLimitsForResolvConf() {
@@ -246,6 +321,94 @@ func (kl *Kubelet) parseResolvConf(reader io.Reader) (nameservers []string, sear
 	return nameservers, searches, options, nil
 }
 
+// GetClusterDNS returns a list of the DNS servers, a list of the DNS search
+// domains of the cluster, and a list of resolv.conf options.
+func (kl *Kubelet) GetClusterDNS(pod *v1.Pod) ([]string, []string, []string, bool, error) {
+	var hostDNS, hostSearch, hostOptions []string
+	// Get host DNS settings
+	if kl.resolverConfig != "" {
+		f, err := os.Open(kl.resolverConfig)
+		if err != nil {
+			return nil, nil, nil, false, err
+		}
+		defer f.Close()
+
+		hostDNS, hostSearch, hostOptions, err = kl.parseResolvConf(f)
+		if err != nil {
+			return nil, nil, nil, false, err
+		}
+	}
+	useClusterFirstPolicy := ((pod.Spec.DNSPolicy == v1.DNSClusterFirst && !kubecontainer.IsHostNetworkPod(pod)) || pod.Spec.DNSPolicy == v1.DNSClusterFirstWithHostNet)
+	if useClusterFirstPolicy && len(kl.clusterDNS) == 0 {
+		// clusterDNS is not known.
+		// pod with ClusterDNSFirst Policy cannot be created
+		kl.recorder.Eventf(pod, v1.EventTypeWarning, "MissingClusterDNS", "kubelet does not have ClusterDNS IP configured and cannot create Pod using %q policy. Falling back to DNSDefault policy.", pod.Spec.DNSPolicy)
+		log := fmt.Sprintf("kubelet does not have ClusterDNS IP configured and cannot create Pod using %q policy. pod: %q. Falling back to DNSDefault policy.", pod.Spec.DNSPolicy, format.Pod(pod))
+		kl.recorder.Eventf(kl.nodeRef, v1.EventTypeWarning, "MissingClusterDNS", log)
+
+		// fallback to DNSDefault
+		useClusterFirstPolicy = false
+	}
+
+	if !useClusterFirstPolicy {
+		// When the kubelet --resolv-conf flag is set to the empty string, use
+		// DNS settings that override the docker default (which is to use
+		// /etc/resolv.conf) and effectively disable DNS lookups. According to
+		// the bind documentation, the behavior of the DNS client library when
+		// "nameservers" are not specified is to "use the nameserver on the
+		// local machine". A nameserver setting of localhost is equivalent to
+		// this documented behavior.
+		if kl.resolverConfig == "" {
+			hostDNS = []string{"127.0.0.1"}
+			hostSearch = []string{"."}
+		} else {
+			hostSearch = kl.formDNSSearchForDNSDefault(hostSearch, pod)
+		}
+		return hostDNS, hostSearch, hostOptions, useClusterFirstPolicy, nil
+	}
+
+	// for a pod with DNSClusterFirst policy, the cluster DNS server is the only nameserver configured for
+	// the pod. The cluster DNS server itself will forward queries to other nameservers that is configured to use,
+	// in case the cluster DNS server cannot resolve the DNS query itself
+	dns := make([]string, len(kl.clusterDNS))
+	for i, ip := range kl.clusterDNS {
+		dns[i] = ip.String()
+	}
+	dnsSearch := kl.formDNSSearch(hostSearch, pod)
+
+	return dns, dnsSearch, hostOptions, useClusterFirstPolicy, nil
+}
+
+// Replace the nameserver in containerized-mounter's rootfs/etc/resolve.conf with kubelet.ClusterDNS
+func (kl *Kubelet) setupDNSinContainerizedMounter(mounterPath string) {
+	resolvePath := filepath.Join(strings.TrimSuffix(mounterPath, "/mounter"), "rootfs", "etc", "resolv.conf")
+	dnsString := ""
+	for _, dns := range kl.clusterDNS {
+		dnsString = dnsString + fmt.Sprintf("nameserver %s\n", dns)
+	}
+	if kl.resolverConfig != "" {
+		f, err := os.Open(kl.resolverConfig)
+		defer f.Close()
+		if err != nil {
+			glog.Error("Could not open resolverConf file")
+		} else {
+			_, hostSearch, _, err := kl.parseResolvConf(f)
+			if err != nil {
+				glog.Errorf("Error for parsing the reslov.conf file: %v", err)
+			} else {
+				dnsString = dnsString + "search"
+				for _, search := range hostSearch {
+					dnsString = dnsString + fmt.Sprintf(" %s", search)
+				}
+				dnsString = dnsString + "\n"
+			}
+		}
+	}
+	if err := ioutil.WriteFile(resolvePath, []byte(dnsString), 0600); err != nil {
+		glog.Errorf("Could not write dns nameserver in file %s, with error %v", resolvePath, err)
+	}
+}
+
 // syncNetworkStatus updates the network state
 func (kl *Kubelet) syncNetworkStatus() {
 	// For cri integration, network state will be updated in updateRuntimeUp,

pkg/kubelet/kubelet_network_test.go

@@ -28,6 +28,76 @@ import (
 	"k8s.io/client-go/tools/record"
 )
 
+func TestNetworkHostGetsPodNotFound(t *testing.T) {
+	testKubelet := newTestKubelet(t, true)
+	defer testKubelet.Cleanup()
+	nh := networkHost{testKubelet.kubelet}
+
+	actualPod, _ := nh.GetPodByName("", "")
+	if actualPod != nil {
+		t.Fatalf("Was expected nil, received %v instead", actualPod)
+	}
+}
+
+func TestNetworkHostGetsKubeClient(t *testing.T) {
+	testKubelet := newTestKubelet(t, true)
+	defer testKubelet.Cleanup()
+	nh := networkHost{testKubelet.kubelet}
+
+	if nh.GetKubeClient() != testKubelet.fakeKubeClient {
+		t.Fatalf("NetworkHost client does not match testKubelet's client")
+	}
+}
+
+func TestNetworkHostGetsRuntime(t *testing.T) {
+	testKubelet := newTestKubelet(t, true)
+	defer testKubelet.Cleanup()
+	nh := networkHost{testKubelet.kubelet}
+
+	if nh.GetRuntime() != testKubelet.fakeRuntime {
+		t.Fatalf("NetworkHost runtime does not match testKubelet's runtime")
+	}
+}
+
+func TestNetworkHostSupportsLegacyFeatures(t *testing.T) {
+	testKubelet := newTestKubelet(t, true)
+	defer testKubelet.Cleanup()
+	nh := networkHost{testKubelet.kubelet}
+
+	if nh.SupportsLegacyFeatures() == false {
+		t.Fatalf("SupportsLegacyFeatures should not be false")
+	}
+}
+
+func TestNoOpHostGetsName(t *testing.T) {
+	nh := NoOpLegacyHost{}
+	pod, err := nh.GetPodByName("", "")
+	if pod != nil && err != true {
+		t.Fatalf("noOpLegacyHost getpodbyname expected to be nil and true")
+	}
+}
+
+func TestNoOpHostGetsKubeClient(t *testing.T) {
+	nh := NoOpLegacyHost{}
+	if nh.GetKubeClient() != nil {
+		t.Fatalf("noOpLegacyHost client expected to be nil")
+	}
+}
+
+func TestNoOpHostGetsRuntime(t *testing.T) {
+	nh := NoOpLegacyHost{}
+	if nh.GetRuntime() != nil {
+		t.Fatalf("noOpLegacyHost runtime expected to be nil")
+	}
+}
+
+func TestNoOpHostSupportsLegacyFeatures(t *testing.T) {
+	nh := NoOpLegacyHost{}
+	if nh.SupportsLegacyFeatures() != false {
+		t.Fatalf("noOpLegacyHost legacy features expected to be false")
+	}
+}
+
 func TestNodeIPParam(t *testing.T) {
 	testKubelet := newTestKubelet(t, false /* controllerAttachDetachEnabled */)
 	defer testKubelet.Cleanup()
@@ -183,6 +253,93 @@ func TestComposeDNSSearch(t *testing.T) {
 	}
 }
 
+func TestGetClusterDNS(t *testing.T) {
+	testKubelet := newTestKubelet(t, false /* controllerAttachDetachEnabled */)
+	defer testKubelet.Cleanup()
+	kubelet := testKubelet.kubelet
+
+	clusterNS := "203.0.113.1"
+	kubelet.clusterDomain = "kubernetes.io"
+	kubelet.clusterDNS = []net.IP{net.ParseIP(clusterNS)}
+
+	pods := newTestPods(4)
+	pods[0].Spec.DNSPolicy = v1.DNSClusterFirstWithHostNet
+	pods[1].Spec.DNSPolicy = v1.DNSClusterFirst
+	pods[2].Spec.DNSPolicy = v1.DNSClusterFirst
+	pods[2].Spec.HostNetwork = false
+	pods[3].Spec.DNSPolicy = v1.DNSDefault
+
+	options := make([]struct {
+		DNS       []string
+		DNSSearch []string
+	}, 4)
+	for i, pod := range pods {
+		var err error
+		options[i].DNS, options[i].DNSSearch, _, _, err = kubelet.GetClusterDNS(pod)
+		if err != nil {
+			t.Fatalf("failed to generate container options: %v", err)
+		}
+	}
+	if len(options[0].DNS) != 1 || options[0].DNS[0] != clusterNS {
+		t.Errorf("expected nameserver %s, got %+v", clusterNS, options[0].DNS)
+	}
+	if len(options[0].DNSSearch) == 0 || options[0].DNSSearch[0] != ".svc."+kubelet.clusterDomain {
+		t.Errorf("expected search %s, got %+v", ".svc."+kubelet.clusterDomain, options[0].DNSSearch)
+	}
+	if len(options[1].DNS) != 1 || options[1].DNS[0] != "127.0.0.1" {
+		t.Errorf("expected nameserver 127.0.0.1, got %+v", options[1].DNS)
+	}
+	if len(options[1].DNSSearch) != 1 || options[1].DNSSearch[0] != "." {
+		t.Errorf("expected search \".\", got %+v", options[1].DNSSearch)
+	}
+	if len(options[2].DNS) != 1 || options[2].DNS[0] != clusterNS {
+		t.Errorf("expected nameserver %s, got %+v", clusterNS, options[2].DNS)
+	}
+	if len(options[2].DNSSearch) == 0 || options[2].DNSSearch[0] != ".svc."+kubelet.clusterDomain {
+		t.Errorf("expected search %s, got %+v", ".svc."+kubelet.clusterDomain, options[2].DNSSearch)
+	}
+	if len(options[3].DNS) != 1 || options[3].DNS[0] != "127.0.0.1" {
+		t.Errorf("expected nameserver 127.0.0.1, got %+v", options[3].DNS)
+	}
+	if len(options[3].DNSSearch) != 1 || options[3].DNSSearch[0] != "." {
+		t.Errorf("expected search \".\", got %+v", options[3].DNSSearch)
+	}
+
+	kubelet.resolverConfig = "/etc/resolv.conf"
+	for i, pod := range pods {
+		var err error
+		options[i].DNS, options[i].DNSSearch, _, _, err = kubelet.GetClusterDNS(pod)
+		if err != nil {
+			t.Fatalf("failed to generate container options: %v", err)
+		}
+	}
+	t.Logf("nameservers %+v", options[1].DNS)
+	if len(options[0].DNS) != 1 {
+		t.Errorf("expected cluster nameserver only, got %+v", options[0].DNS)
+	} else if options[0].DNS[0] != clusterNS {
+		t.Errorf("expected nameserver %s, got %v", clusterNS, options[0].DNS[0])
+	}
+	expLength := len(options[1].DNSSearch) + 3
+	if expLength > 6 {
+		expLength = 6
+	}
+	if len(options[0].DNSSearch) != expLength {
+		t.Errorf("expected prepend of cluster domain, got %+v", options[0].DNSSearch)
+	} else if options[0].DNSSearch[0] != ".svc."+kubelet.clusterDomain {
+		t.Errorf("expected domain %s, got %s", ".svc."+kubelet.clusterDomain, options[0].DNSSearch)
+	}
+	if len(options[2].DNS) != 1 {
+		t.Errorf("expected cluster nameserver only, got %+v", options[2].DNS)
+	} else if options[2].DNS[0] != clusterNS {
+		t.Errorf("expected nameserver %s, got %v", clusterNS, options[2].DNS[0])
+	}
+	if len(options[2].DNSSearch) != expLength {
+		t.Errorf("expected prepend of cluster domain, got %+v", options[2].DNSSearch)
+	} else if options[2].DNSSearch[0] != ".svc."+kubelet.clusterDomain {
+		t.Errorf("expected domain %s, got %s", ".svc."+kubelet.clusterDomain, options[0].DNSSearch)
+	}
+}
+
 func TestGetIPTablesMark(t *testing.T) {
 	tests := []struct {
 		bit    int

pkg/kubelet/kubelet_test.go

@@ -19,7 +19,6 @@ package kubelet
 import (
 	"fmt"
 	"io/ioutil"
-	"net"
 	"os"
 	"sort"
 	"testing"
@@ -2171,90 +2170,3 @@ type podsByUID []*v1.Pod
 func (p podsByUID) Len() int           { return len(p) }
 func (p podsByUID) Swap(i, j int)      { p[i], p[j] = p[j], p[i] }
 func (p podsByUID) Less(i, j int) bool { return p[i].UID < p[j].UID }
-
-func TestGetClusterDNS(t *testing.T) {
-	testKubelet := newTestKubelet(t, false /* controllerAttachDetachEnabled */)
-	defer testKubelet.Cleanup()
-	kubelet := testKubelet.kubelet
-
-	clusterNS := "203.0.113.1"
-	kubelet.clusterDomain = "kubernetes.io"
-	kubelet.clusterDNS = []net.IP{net.ParseIP(clusterNS)}
-
-	pods := newTestPods(4)
-	pods[0].Spec.DNSPolicy = v1.DNSClusterFirstWithHostNet
-	pods[1].Spec.DNSPolicy = v1.DNSClusterFirst
-	pods[2].Spec.DNSPolicy = v1.DNSClusterFirst
-	pods[2].Spec.HostNetwork = false
-	pods[3].Spec.DNSPolicy = v1.DNSDefault
-
-	options := make([]struct {
-		DNS       []string
-		DNSSearch []string
-	}, 4)
-	for i, pod := range pods {
-		var err error
-		options[i].DNS, options[i].DNSSearch, _, _, err = kubelet.GetClusterDNS(pod)
-		if err != nil {
-			t.Fatalf("failed to generate container options: %v", err)
-		}
-	}
-	if len(options[0].DNS) != 1 || options[0].DNS[0] != clusterNS {
-		t.Errorf("expected nameserver %s, got %+v", clusterNS, options[0].DNS)
-	}
-	if len(options[0].DNSSearch) == 0 || options[0].DNSSearch[0] != ".svc."+kubelet.clusterDomain {
-		t.Errorf("expected search %s, got %+v", ".svc."+kubelet.clusterDomain, options[0].DNSSearch)
-	}
-	if len(options[1].DNS) != 1 || options[1].DNS[0] != "127.0.0.1" {
-		t.Errorf("expected nameserver 127.0.0.1, got %+v", options[1].DNS)
-	}
-	if len(options[1].DNSSearch) != 1 || options[1].DNSSearch[0] != "." {
-		t.Errorf("expected search \".\", got %+v", options[1].DNSSearch)
-	}
-	if len(options[2].DNS) != 1 || options[2].DNS[0] != clusterNS {
-		t.Errorf("expected nameserver %s, got %+v", clusterNS, options[2].DNS)
-	}
-	if len(options[2].DNSSearch) == 0 || options[2].DNSSearch[0] != ".svc."+kubelet.clusterDomain {
-		t.Errorf("expected search %s, got %+v", ".svc."+kubelet.clusterDomain, options[2].DNSSearch)
-	}
-	if len(options[3].DNS) != 1 || options[3].DNS[0] != "127.0.0.1" {
-		t.Errorf("expected nameserver 127.0.0.1, got %+v", options[3].DNS)
-	}
-	if len(options[3].DNSSearch) != 1 || options[3].DNSSearch[0] != "." {
-		t.Errorf("expected search \".\", got %+v", options[3].DNSSearch)
-	}
-
-	kubelet.resolverConfig = "/etc/resolv.conf"
-	for i, pod := range pods {
-		var err error
-		options[i].DNS, options[i].DNSSearch, _, _, err = kubelet.GetClusterDNS(pod)
-		if err != nil {
-			t.Fatalf("failed to generate container options: %v", err)
-		}
-	}
-	t.Logf("nameservers %+v", options[1].DNS)
-	if len(options[0].DNS) != 1 {
-		t.Errorf("expected cluster nameserver only, got %+v", options[0].DNS)
-	} else if options[0].DNS[0] != clusterNS {
-		t.Errorf("expected nameserver %s, got %v", clusterNS, options[0].DNS[0])
-	}
-	expLength := len(options[1].DNSSearch) + 3
-	if expLength > 6 {
-		expLength = 6
-	}
-	if len(options[0].DNSSearch) != expLength {
-		t.Errorf("expected prepend of cluster domain, got %+v", options[0].DNSSearch)
-	} else if options[0].DNSSearch[0] != ".svc."+kubelet.clusterDomain {
-		t.Errorf("expected domain %s, got %s", ".svc."+kubelet.clusterDomain, options[0].DNSSearch)
-	}
-	if len(options[2].DNS) != 1 {
-		t.Errorf("expected cluster nameserver only, got %+v", options[2].DNS)
-	} else if options[2].DNS[0] != clusterNS {
-		t.Errorf("expected nameserver %s, got %v", clusterNS, options[2].DNS[0])
-	}
-	if len(options[2].DNSSearch) != expLength {
-		t.Errorf("expected prepend of cluster domain, got %+v", options[2].DNSSearch)
-	} else if options[2].DNSSearch[0] != ".svc."+kubelet.clusterDomain {
-		t.Errorf("expected domain %s, got %s", ".svc."+kubelet.clusterDomain, options[0].DNSSearch)
-	}
-}

pkg/kubelet/networks.go

@@ -1,95 +0,0 @@
-/*
-Copyright 2014 The Kubernetes Authors.
-
-Licensed under the Apache License, Version 2.0 (the "License");
-you may not use this file except in compliance with the License.
-You may obtain a copy of the License at
-
-    http://www.apache.org/licenses/LICENSE-2.0
-
-Unless required by applicable law or agreed to in writing, software
-distributed under the License 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 kubelet
-
-import (
-	"k8s.io/api/core/v1"
-	clientset "k8s.io/client-go/kubernetes"
-	kubecontainer "k8s.io/kubernetes/pkg/kubelet/container"
-	"k8s.io/kubernetes/pkg/kubelet/network"
-)
-
-// This just exports required functions from kubelet proper, for use by network
-// plugins.
-// TODO(#35457): get rid of this backchannel to the kubelet. The scope of
-// the back channel is restricted to host-ports/testing, and restricted
-// to kubenet. No other network plugin wrapper needs it. Other plugins
-// only require a way to access namespace information, which they can do
-// directly through the methods implemented by criNetworkHost.
-type networkHost struct {
-	kubelet *Kubelet
-}
-
-func (nh *networkHost) GetPodByName(name, namespace string) (*v1.Pod, bool) {
-	return nh.kubelet.GetPodByName(name, namespace)
-}
-
-func (nh *networkHost) GetKubeClient() clientset.Interface {
-	return nh.kubelet.kubeClient
-}
-
-func (nh *networkHost) GetRuntime() kubecontainer.Runtime {
-	return nh.kubelet.GetRuntime()
-}
-
-func (nh *networkHost) SupportsLegacyFeatures() bool {
-	return true
-}
-
-// criNetworkHost implements the part of network.Host required by the
-// cri (NamespaceGetter). It leechs off networkHost for all other
-// methods, because networkHost is slated for deletion.
-type criNetworkHost struct {
-	*networkHost
-	// criNetworkHost currently support legacy features. Hence no need to support PortMappingGetter
-	*network.NoopPortMappingGetter
-}
-
-// GetNetNS returns the network namespace of the given containerID.
-// This method satisfies the network.NamespaceGetter interface for
-// networkHost. It's only meant to be used from network plugins
-// that are directly invoked by the kubelet (aka: legacy, pre-cri).
-// Any network plugin invoked by a cri must implement NamespaceGetter
-// to talk directly to the runtime instead.
-func (c *criNetworkHost) GetNetNS(containerID string) (string, error) {
-	return c.kubelet.GetRuntime().GetNetNS(kubecontainer.ContainerID{Type: "", ID: containerID})
-}
-
-// NoOpLegacyHost implements the network.LegacyHost interface for the remote
-// runtime shim by just returning empties. It doesn't support legacy features
-// like host port and bandwidth shaping.
-type NoOpLegacyHost struct{}
-
-// GetPodByName always returns "nil, true" for 'NoOpLegacyHost'
-func (n *NoOpLegacyHost) GetPodByName(namespace, name string) (*v1.Pod, bool) {
-	return nil, true
-}
-
-// GetKubeClient always returns "nil" for 'NoOpLegacyHost'
-func (n *NoOpLegacyHost) GetKubeClient() clientset.Interface {
-	return nil
-}
-
-// GetRuntime always returns "nil" for 'NoOpLegacyHost'
-func (n *NoOpLegacyHost) GetRuntime() kubecontainer.Runtime {
-	return nil
-}
-
-// SupportsLegacyFeatures always returns "false" for 'NoOpLegacyHost'
-func (n *NoOpLegacyHost) SupportsLegacyFeatures() bool {
-	return false
-}

pkg/kubelet/networks_test.go

@@ -1,91 +0,0 @@
-/*
-Copyright 2017 The Kubernetes Authors.
-
-Licensed under the Apache License, Version 2.0 (the "License");
-you may not use this file except in compliance with the License.
-You may obtain a copy of the License at
-
-    http://www.apache.org/licenses/LICENSE-2.0
-
-Unless required by applicable law or agreed to in writing, software
-distributed under the License 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 kubelet
-
-import (
-	"testing"
-)
-
-func TestNetworkHostGetsPodNotFound(t *testing.T) {
-	testKubelet := newTestKubelet(t, true)
-	defer testKubelet.Cleanup()
-	nh := networkHost{testKubelet.kubelet}
-
-	actualPod, _ := nh.GetPodByName("", "")
-	if actualPod != nil {
-		t.Fatalf("Was expected nil, received %v instead", actualPod)
-	}
-}
-
-func TestNetworkHostGetsKubeClient(t *testing.T) {
-	testKubelet := newTestKubelet(t, true)
-	defer testKubelet.Cleanup()
-	nh := networkHost{testKubelet.kubelet}
-
-	if nh.GetKubeClient() != testKubelet.fakeKubeClient {
-		t.Fatalf("NetworkHost client does not match testKubelet's client")
-	}
-}
-
-func TestNetworkHostGetsRuntime(t *testing.T) {
-	testKubelet := newTestKubelet(t, true)
-	defer testKubelet.Cleanup()
-	nh := networkHost{testKubelet.kubelet}
-
-	if nh.GetRuntime() != testKubelet.fakeRuntime {
-		t.Fatalf("NetworkHost runtime does not match testKubelet's runtime")
-	}
-}
-
-func TestNetworkHostSupportsLegacyFeatures(t *testing.T) {
-	testKubelet := newTestKubelet(t, true)
-	defer testKubelet.Cleanup()
-	nh := networkHost{testKubelet.kubelet}
-
-	if nh.SupportsLegacyFeatures() == false {
-		t.Fatalf("SupportsLegacyFeatures should not be false")
-	}
-}
-
-func TestNoOpHostGetsName(t *testing.T) {
-	nh := NoOpLegacyHost{}
-	pod, err := nh.GetPodByName("", "")
-	if pod != nil && err != true {
-		t.Fatalf("noOpLegacyHost getpodbyname expected to be nil and true")
-	}
-}
-
-func TestNoOpHostGetsKubeClient(t *testing.T) {
-	nh := NoOpLegacyHost{}
-	if nh.GetKubeClient() != nil {
-		t.Fatalf("noOpLegacyHost client expected to be nil")
-	}
-}
-
-func TestNoOpHostGetsRuntime(t *testing.T) {
-	nh := NoOpLegacyHost{}
-	if nh.GetRuntime() != nil {
-		t.Fatalf("noOpLegacyHost runtime expected to be nil")
-	}
-}
-
-func TestNoOpHostSupportsLegacyFeatures(t *testing.T) {
-	nh := NoOpLegacyHost{}
-	if nh.SupportsLegacyFeatures() != false {
-		t.Fatalf("noOpLegacyHost legacy features expected to be false")
-	}
-}