Multi-cluster fixes

- Avoid IP address conflicts by running each cluser & namespace with its own IP address - Include context in the hash key used to store services, so that services with the same name & namespace from different clusters can co-exist - Use the same naming scheme for services regardless of whether they are the first cluster on the list or not
txn2 · Aug 29, 2020 · 0ff8add · 0ff8add
1 parent 19fc921
commit 0ff8add
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Showing 4 changed files with 38 additions and 71 deletions.
diff --git a/cmd/kubefwd/services/services.go b/cmd/kubefwd/services/services.go
@@ -245,6 +245,9 @@ Try:
 
 	nsWatchesDone := &sync.WaitGroup{} // We'll wait on this to exit the program. Done() indicates that all namespace watches have shutdown cleanly.
 
+	// ShortName field only used if one namespace/context
+	useFullName := len(namespaces) > 1 || len(contexts) > 1
+
 	for i, ctx := range contexts {
 		// k8s REST config
 		restConfig, err := configGetter.GetRestConfig(cfgFilePath, ctx)
@@ -273,8 +276,7 @@ Try:
 
 		for ii, namespace := range namespaces {
 			nsWatchesDone.Add(1)
-			go func(ii int, namespace string) {
-				// ShortName field only use short name for the first namespace and context
+			go func(ctx string, namespace string, ipC int, ipD int) {
 				nameSpaceOpts := NamespaceOpts{
 					ClientSet:         clientSet,
 					Context:           ctx,
@@ -284,16 +286,15 @@ Try:
 					Hostfile:          &fwdport.HostFileWithLock{Hosts: hostFile},
 					ClientConfig:      restConfig,
 					RESTClient:        restClient,
-					ShortName:         i < 1 && ii < 1,
-					Remote:            i > 0,
-					IpC:               byte(ipC + ii),
+					ShortName:         !useFullName,
+					IpC:               byte(ipC),
 					IpD:               ipD,
 					Domain:            domain,
 					ManualStopChannel: stopListenCh,
 				}
 				nameSpaceOpts.watchServiceEvents(stopListenCh)
 				nsWatchesDone.Done()
-			}(ii, namespace)
+			}(ctx, namespace, ipC+i, ipD+ii)
 		}
 	}
 
@@ -316,7 +317,6 @@ type NamespaceOpts struct {
 	ClientConfig      *restclient.Config
 	RESTClient        *restclient.RESTClient
 	ShortName         bool
-	Remote            bool
 	IpC               byte
 	IpD               int
 	Domain            string
@@ -357,7 +357,7 @@ func (opts *NamespaceOpts) watchServiceEvents(stopListenCh <-chan struct{}) {
 
 	// Start the informer, blocking call until we receive a stop signal
 	controller.Run(stopListenCh)
-	log.Infof("Stopped watching Service events in namespace %s", opts.Namespace)
+	log.Infof("Stopped watching Service events in namespace %s, context %s", opts.Namespace, opts.Context)
 }
 
 // AddServiceHandler is the event handler for when a new service comes in from k8s (the initial list of services will also be coming in using this event for each).
@@ -383,7 +383,6 @@ func (opts *NamespaceOpts) AddServiceHandler(obj interface{}) {
 		ClientConfig:     opts.ClientConfig,
 		RESTClient:       opts.RESTClient,
 		ShortName:        opts.ShortName,
-		Remote:           opts.Remote,
 		IpC:              opts.IpC,
 		IpD:              &opts.IpD,
 		Domain:           opts.Domain,

diff --git a/cmd/kubefwd/services/services_test.go b/cmd/kubefwd/services/services_test.go
@@ -123,7 +123,6 @@ func buildFwdServiceOpts(t *testing.T, namespace string) *FwdServiceOpts {
 		ClientConfig: restConfig,
 		RESTClient:   restClient,
 		ShortName:    true,
-		Remote:       false,
 		IpC:          byte(ipC),
 		IpD:          ipD,
 		ExitOnFail:   exitOnFail,

diff --git a/pkg/fwdport/fwdport.go b/pkg/fwdport/fwdport.go
@@ -56,7 +56,6 @@ type PortForwardOpts struct {
 	LocalPort      string
 	Hostfile       *HostFileWithLock
 	ShortName      bool
-	Remote         bool
 	Domain         string
 	HostsParams    *HostsParams
 	ManualStopChan chan struct{} // Send a signal on this to stop the portforwarding
@@ -154,11 +153,8 @@ func (pfo *PortForwardOpts) BuildTheHostsParams() {
 	pfo.HostsParams = &HostsParams{}
 	localServiceName := pfo.Service
 	nsServiceName := pfo.Service + "." + pfo.Namespace
-	fullServiceName := fmt.Sprintf("%s.%s.svc.cluster.local", pfo.Service, pfo.Namespace)
+	fullServiceName := fmt.Sprintf("%s.%s.svc.cluster.%s", pfo.Service, pfo.Namespace, pfo.Context)
 	svcServiceName := fmt.Sprintf("%s.%s.svc", pfo.Service, pfo.Namespace)
-	if pfo.Remote {
-		fullServiceName = fmt.Sprintf("%s.%s.svc.cluster.%s", pfo.Service, pfo.Namespace, pfo.Context)
-	}
 	pfo.HostsParams.localServiceName = localServiceName
 	pfo.HostsParams.nsServiceName = nsServiceName
 	pfo.HostsParams.fullServiceName = fullServiceName
@@ -169,40 +165,27 @@ func (pfo *PortForwardOpts) BuildTheHostsParams() {
 func (pfo *PortForwardOpts) AddHosts() {
 
 	pfo.Hostfile.Lock()
-	if pfo.Remote {
-
-		pfo.Hostfile.Hosts.RemoveHost(pfo.HostsParams.fullServiceName)
-		pfo.Hostfile.Hosts.RemoveHost(pfo.HostsParams.svcServiceName)
+	if pfo.ShortName {
 		if pfo.Domain != "" {
-			pfo.Hostfile.Hosts.AddHost(pfo.LocalIp.String(), pfo.Service+"."+pfo.Domain)
-		}
-		pfo.Hostfile.Hosts.AddHost(pfo.LocalIp.String(), pfo.Service)
-
-	} else {
-
-		if pfo.ShortName {
-			if pfo.Domain != "" {
-				pfo.Hostfile.Hosts.RemoveHost(pfo.HostsParams.localServiceName + "." + pfo.Domain)
-				pfo.Hostfile.Hosts.AddHost(pfo.LocalIp.String(), pfo.HostsParams.localServiceName+"."+pfo.Domain)
-			}
-			pfo.Hostfile.Hosts.RemoveHost(pfo.HostsParams.localServiceName)
-			pfo.Hostfile.Hosts.AddHost(pfo.LocalIp.String(), pfo.HostsParams.localServiceName)
+			pfo.Hostfile.Hosts.RemoveHost(pfo.HostsParams.localServiceName + "." + pfo.Domain)
+			pfo.Hostfile.Hosts.AddHost(pfo.LocalIp.String(), pfo.HostsParams.localServiceName+"."+pfo.Domain)
 		}
+		pfo.Hostfile.Hosts.RemoveHost(pfo.HostsParams.localServiceName)
+		pfo.Hostfile.Hosts.AddHost(pfo.LocalIp.String(), pfo.HostsParams.localServiceName)
+	}
 
-		pfo.Hostfile.Hosts.RemoveHost(pfo.HostsParams.fullServiceName)
-		pfo.Hostfile.Hosts.AddHost(pfo.LocalIp.String(), pfo.HostsParams.fullServiceName)
-
-		pfo.Hostfile.Hosts.RemoveHost(pfo.HostsParams.svcServiceName)
-		pfo.Hostfile.Hosts.AddHost(pfo.LocalIp.String(), pfo.HostsParams.svcServiceName)
+	pfo.Hostfile.Hosts.RemoveHost(pfo.HostsParams.fullServiceName)
+	pfo.Hostfile.Hosts.AddHost(pfo.LocalIp.String(), pfo.HostsParams.fullServiceName)
 
-		if pfo.Domain != "" {
-			pfo.Hostfile.Hosts.RemoveHost(pfo.HostsParams.nsServiceName + "." + pfo.Domain)
-			pfo.Hostfile.Hosts.AddHost(pfo.LocalIp.String(), pfo.HostsParams.nsServiceName+"."+pfo.Domain)
-		}
-		pfo.Hostfile.Hosts.RemoveHost(pfo.HostsParams.nsServiceName)
-		pfo.Hostfile.Hosts.AddHost(pfo.LocalIp.String(), pfo.HostsParams.nsServiceName)
+	pfo.Hostfile.Hosts.RemoveHost(pfo.HostsParams.svcServiceName)
+	pfo.Hostfile.Hosts.AddHost(pfo.LocalIp.String(), pfo.HostsParams.svcServiceName)
 
+	if pfo.Domain != "" {
+		pfo.Hostfile.Hosts.RemoveHost(pfo.HostsParams.nsServiceName + "." + pfo.Domain)
+		pfo.Hostfile.Hosts.AddHost(pfo.LocalIp.String(), pfo.HostsParams.nsServiceName+"."+pfo.Domain)
 	}
+	pfo.Hostfile.Hosts.RemoveHost(pfo.HostsParams.nsServiceName)
+	pfo.Hostfile.Hosts.AddHost(pfo.LocalIp.String(), pfo.HostsParams.nsServiceName)
 	err := pfo.Hostfile.Hosts.Save()
 	if err != nil {
 		log.Error("Error saving hosts file", err)
@@ -223,18 +206,16 @@ func (pfo *PortForwardOpts) removeHosts() {
 		return
 	}
 
-	if !pfo.Remote {
-		if pfo.Domain != "" {
-			// fmt.Printf("removeHost: %s\r\n", (pfo.HostsParams.localServiceName + "." + pfo.Domain))
-			// fmt.Printf("removeHost: %s\r\n", (pfo.HostsParams.nsServiceName + "." + pfo.Domain))
-			pfo.Hostfile.Hosts.RemoveHost(pfo.HostsParams.localServiceName + "." + pfo.Domain)
-			pfo.Hostfile.Hosts.RemoveHost(pfo.HostsParams.nsServiceName + "." + pfo.Domain)
-		}
-		// fmt.Printf("removeHost: %s\r\n", pfo.HostsParams.localServiceName)
-		// fmt.Printf("removeHost: %s\r\n", pfo.HostsParams.nsServiceName)
-		pfo.Hostfile.Hosts.RemoveHost(pfo.HostsParams.localServiceName)
-		pfo.Hostfile.Hosts.RemoveHost(pfo.HostsParams.nsServiceName)
+	if pfo.Domain != "" {
+		// fmt.Printf("removeHost: %s\r\n", (pfo.HostsParams.localServiceName + "." + pfo.Domain))
+		// fmt.Printf("removeHost: %s\r\n", (pfo.HostsParams.nsServiceName + "." + pfo.Domain))
+		pfo.Hostfile.Hosts.RemoveHost(pfo.HostsParams.localServiceName + "." + pfo.Domain)
+		pfo.Hostfile.Hosts.RemoveHost(pfo.HostsParams.nsServiceName + "." + pfo.Domain)
 	}
+	// fmt.Printf("removeHost: %s\r\n", pfo.HostsParams.localServiceName)
+	// fmt.Printf("removeHost: %s\r\n", pfo.HostsParams.nsServiceName)
+	pfo.Hostfile.Hosts.RemoveHost(pfo.HostsParams.localServiceName)
+	pfo.Hostfile.Hosts.RemoveHost(pfo.HostsParams.nsServiceName)
 	// fmt.Printf("removeHost: %s\r\n", pfo.HostsParams.fullServiceName)
 	pfo.Hostfile.Hosts.RemoveHost(pfo.HostsParams.fullServiceName)
 	pfo.Hostfile.Hosts.RemoveHost(pfo.HostsParams.svcServiceName)

diff --git a/pkg/fwdservice/fwdservice.go b/pkg/fwdservice/fwdservice.go
@@ -29,7 +29,6 @@ type ServiceFWD struct {
 	ClientConfig *restclient.Config
 	RESTClient   *restclient.RESTClient
 	ShortName    bool
-	Remote       bool
 	IpC          byte
 	IpD          *int
 	Domain       string
@@ -44,7 +43,7 @@ type ServiceFWD struct {
 }
 
 func (svcFwd *ServiceFWD) String() string {
-	return svcFwd.Svc.Name + "." + svcFwd.Namespace
+	return svcFwd.Svc.Name + "." + svcFwd.Namespace + "." + svcFwd.Context
 }
 
 // GetPodsForService queries k8s and returns all pods backing this service
@@ -189,25 +188,15 @@ func (svcfwd *ServiceFWD) LoopPodsToForward(pods []v1.Pod, includePodNameInHost
 
 			svcName = serviceHostName
 
-			if !svcfwd.ShortName {
-				serviceHostName = serviceHostName + "." + pod.Namespace
-			}
-
-			if svcfwd.Domain != "" {
-				serviceHostName = serviceHostName + "." + svcfwd.Domain
-			}
-
-			if svcfwd.Remote {
-				serviceHostName = fmt.Sprintf("%s.svc.cluster.%s", serviceHostName, svcfwd.Context)
-			}
-
 			log.Debugf("Resolving:    %s to %s\n",
 				serviceHostName,
 				localIp.String(),
 			)
 
-			log.Printf("Port-Forward: %s:%d to pod %s:%s\n",
-				serviceHostName,
+			log.Printf("Port-Forward: %s.%s.svc.cluster.%s:%d to pod %s:%s\n",
+				svcfwd.Svc.Name,
+				svcfwd.Svc.Namespace,
+				svcfwd.Context,
 				port.Port,
 				pod.Name,
 				podPort,
@@ -228,7 +217,6 @@ func (svcfwd *ServiceFWD) LoopPodsToForward(pods []v1.Pod, includePodNameInHost
 				LocalPort:  localPort,
 				Hostfile:   svcfwd.Hostfile,
 				ShortName:  svcfwd.ShortName,
-				Remote:     svcfwd.Remote,
 				Domain:     svcfwd.Domain,
 
 				ManualStopChan: make(chan struct{}),