Fix some lint errors in pkg/proxy

cmd/kube-proxy/app/server_others.go

@@ -237,7 +237,7 @@ func newProxyServer(
 	}, nil
 }
 
-func getProxyMode(proxyMode string, iptver iptables.IPTablesVersioner, khandle ipvs.KernelHandler, ipsetver ipvs.IPSetVersioner, kcompat iptables.KernelCompatTester) string {
+func getProxyMode(proxyMode string, iptver iptables.Versioner, khandle ipvs.KernelHandler, ipsetver ipvs.IPSetVersioner, kcompat iptables.KernelCompatTester) string {
 	switch proxyMode {
 	case proxyModeUserspace:
 		return proxyModeUserspace
@@ -250,7 +250,7 @@ func getProxyMode(proxyMode string, iptver iptables.IPTablesVersioner, khandle i
 	return tryIPTablesProxy(iptver, kcompat)
 }
 
-func tryIPVSProxy(iptver iptables.IPTablesVersioner, khandle ipvs.KernelHandler, ipsetver ipvs.IPSetVersioner, kcompat iptables.KernelCompatTester) string {
+func tryIPVSProxy(iptver iptables.Versioner, khandle ipvs.KernelHandler, ipsetver ipvs.IPSetVersioner, kcompat iptables.KernelCompatTester) string {
 	// guaranteed false on error, error only necessary for debugging
 	// IPVS Proxier relies on ip_vs_* kernel modules and ipset
 	useIPVSProxy, err := ipvs.CanUseIPVSProxier(khandle, ipsetver)
@@ -267,7 +267,7 @@ func tryIPVSProxy(iptver iptables.IPTablesVersioner, khandle ipvs.KernelHandler,
 	return tryIPTablesProxy(iptver, kcompat)
 }
 
-func tryIPTablesProxy(iptver iptables.IPTablesVersioner, kcompat iptables.KernelCompatTester) string {
+func tryIPTablesProxy(iptver iptables.Versioner, kcompat iptables.KernelCompatTester) string {
 	// guaranteed false on error, error only necessary for debugging
 	useIPTablesProxy, err := iptables.CanUseIPTablesProxier(iptver, kcompat)
 	if err != nil {

hack/.golint_failures

@@ -194,9 +194,7 @@ pkg/master/tunneler
 pkg/proxy
 pkg/proxy/apis/config
 pkg/proxy/apis/config/v1alpha1
-pkg/proxy/iptables
 pkg/proxy/userspace
-pkg/proxy/util
 pkg/proxy/winkernel
 pkg/proxy/winuserspace
 pkg/quota/v1/evaluator/core

pkg/proxy/iptables/proxier.go

@@ -73,18 +73,18 @@ const (
 	// the kubernetes postrouting chain
 	kubePostroutingChain utiliptables.Chain = "KUBE-POSTROUTING"
 
-	// the mark-for-masquerade chain
+	// KubeMarkMasqChain is the mark-for-masquerade chain
 	KubeMarkMasqChain utiliptables.Chain = "KUBE-MARK-MASQ"
 
-	// the mark-for-drop chain
+	// KubeMarkDropChain is the mark-for-drop chain
 	KubeMarkDropChain utiliptables.Chain = "KUBE-MARK-DROP"
 
 	// the kubernetes forward chain
 	kubeForwardChain utiliptables.Chain = "KUBE-FORWARD"
 )
 
-// IPTablesVersioner can query the current iptables version.
-type IPTablesVersioner interface {
+// Versioner can query the current iptables version.
+type Versioner interface {
 	// returns "X.Y.Z"
 	GetVersion() (string, error)
 }
@@ -100,7 +100,7 @@ type KernelCompatTester interface {
 // the iptables version and for the existence of kernel features. It may return
 // an error if it fails to get the iptables version without error, in which
 // case it will also return false.
-func CanUseIPTablesProxier(iptver IPTablesVersioner, kcompat KernelCompatTester) (bool, error) {
+func CanUseIPTablesProxier(iptver Versioner, kcompat KernelCompatTester) (bool, error) {
 	minVersion, err := utilversion.ParseGeneric(iptablesMinVersion)
 	if err != nil {
 		return false, err
@@ -124,12 +124,14 @@ func CanUseIPTablesProxier(iptver IPTablesVersioner, kcompat KernelCompatTester)
 	return true, nil
 }
 
+// LinuxKernelCompatTester is the Linux implementation of KernelCompatTester
 type LinuxKernelCompatTester struct{}
 
+// IsCompatible checks for the required sysctls.  We don't care about the value, just
+// that it exists.  If this Proxier is chosen, we'll initialize it as we
+// need.
 func (lkct LinuxKernelCompatTester) IsCompatible() error {
-	// Check for the required sysctls.  We don't care about the value, just
-	// that it exists.  If this Proxier is chosen, we'll initialize it as we
-	// need.
+
 	_, err := utilsysctl.New().GetSysctl(sysctlRouteLocalnet)
 	return err
 }
@@ -507,21 +509,29 @@ func (proxier *Proxier) isInitialized() bool {
 	return atomic.LoadInt32(&proxier.initialized) > 0
 }
 
+// OnServiceAdd is called whenever creation of new service object
+// is observed.
 func (proxier *Proxier) OnServiceAdd(service *v1.Service) {
 	proxier.OnServiceUpdate(nil, service)
 }
 
+// OnServiceUpdate is called whenever modification of an existing
+// service object is observed.
 func (proxier *Proxier) OnServiceUpdate(oldService, service *v1.Service) {
 	if proxier.serviceChanges.Update(oldService, service) && proxier.isInitialized() {
 		proxier.syncRunner.Run()
 	}
 }
 
+// OnServiceDelete is called whenever deletion of an existing service
+// object is observed.
 func (proxier *Proxier) OnServiceDelete(service *v1.Service) {
 	proxier.OnServiceUpdate(service, nil)
 
 }
 
+// OnServiceSynced is called once all the initial even handlers were
+// called and the state is fully propagated to local cache.
 func (proxier *Proxier) OnServiceSynced() {
 	proxier.mu.Lock()
 	proxier.servicesSynced = true
@@ -532,20 +542,28 @@ func (proxier *Proxier) OnServiceSynced() {
 	proxier.syncProxyRules()
 }
 
+// OnEndpointsAdd is called whenever creation of new endpoints object
+// is observed.
 func (proxier *Proxier) OnEndpointsAdd(endpoints *v1.Endpoints) {
 	proxier.OnEndpointsUpdate(nil, endpoints)
 }
 
+// OnEndpointsUpdate is called whenever modification of an existing
+// endpoints object is observed.
 func (proxier *Proxier) OnEndpointsUpdate(oldEndpoints, endpoints *v1.Endpoints) {
 	if proxier.endpointsChanges.Update(oldEndpoints, endpoints) && proxier.isInitialized() {
 		proxier.syncRunner.Run()
 	}
 }
 
+// OnEndpointsDelete is called whever deletion of an existing endpoints
+// object is observed.
 func (proxier *Proxier) OnEndpointsDelete(endpoints *v1.Endpoints) {
 	proxier.OnEndpointsUpdate(endpoints, nil)
 }
 
+// OnEndpointsSynced is called once all the initial event handlers were
+// called and the state is fully propagated to local cache.
 func (proxier *Proxier) OnEndpointsSynced() {
 	proxier.mu.Lock()
 	proxier.endpointsSynced = true

pkg/proxy/util/endpoints.go

@@ -39,12 +39,12 @@ func IPPart(s string) string {
 		return ""
 	}
 	// Check if host string is a valid IP address
-	if ip := net.ParseIP(host); ip != nil {
-		return ip.String()
-	} else {
+	ip := net.ParseIP(host)
+	if ip == nil {
 		klog.Errorf("invalid IP part '%s'", host)
+		return ""
 	}
-	return ""
+	return ip.String()
 }
 
 // PortPart returns just the port part of an endpoint string.

pkg/proxy/util/utils.go

@@ -33,15 +33,23 @@ import (
 )
 
 const (
+	// IPv4ZeroCIDR is the CIDR block for the whole IPv4 address space
 	IPv4ZeroCIDR = "0.0.0.0/0"
+
+	// IPv6ZeroCIDR is the CIDR block for the whole IPv6 address space
 	IPv6ZeroCIDR = "::/0"
 )
 
 var (
+	// ErrAddressNotAllowed indicates the address is not allowed
 	ErrAddressNotAllowed = errors.New("address not allowed")
-	ErrNoAddresses       = errors.New("No addresses for hostname")
+
+	// ErrNoAddresses indicates there are no addresses for the hostname
+	ErrNoAddresses = errors.New("No addresses for hostname")
 )
 
+// IsZeroCIDR checks whether the input CIDR string is either
+// the IPv4 or IPv6 zero CIDR
 func IsZeroCIDR(cidr string) bool {
 	if cidr == IPv4ZeroCIDR || cidr == IPv6ZeroCIDR {
 		return true
@@ -89,6 +97,8 @@ func IsProxyableHostname(ctx context.Context, resolv Resolver, hostname string)
 	return nil
 }
 
+// IsLocalIP checks if a given IP address is bound to an interface
+// on the local system
 func IsLocalIP(ip string) (bool, error) {
 	addrs, err := net.InterfaceAddrs()
 	if err != nil {
@@ -106,6 +116,7 @@ func IsLocalIP(ip string) (bool, error) {
 	return false, nil
 }
 
+// ShouldSkipService checks if a given service should skip proxying
 func ShouldSkipService(svcName types.NamespacedName, service *v1.Service) bool {
 	// if ClusterIP is "None" or empty, skip proxying
 	if !helper.IsServiceIPSet(service) {