improve ekz to install load balancer by default

Author: chanwit

Makefile

@@ -14,6 +14,10 @@ vet:
 test: tidy fmt vet docs
 	go test ./... -coverprofile cover.out
 
+build-ui:
+	( cd ui && bash -x ./dev.sh )
+	( cd ui && bash -x ./build.sh )
+
 build:
 	CGO_ENABLED=0 go build -o ./bin/ekz ./cmd/ekz
 

cmd/ekz/create_cluster.go

@@ -90,15 +90,21 @@ func createClusterCmdRun(cmd *cobra.Command, args []string) error {
 
 	switch provider {
 	case "ekz":
-		return createClusterEKZ()
+		if err := createClusterEKZ(); err != nil {
+			return err
+		}
 	case "kind":
 		if hostMode == true {
 			return errors.New("the host mode is not supported by the KIND provider")
 		}
-		return createClusterKIND()
+		if err := createClusterKIND(); err != nil {
+			return err
+		}
 	default:
 		return fmt.Errorf("NYI provider: %s", provider)
 	}
+
+	return nil
 }
 
 func waitForNodeStarted(nodeName string, timeout time.Duration) {

cmd/ekz/create_cluster_ekz.go

@@ -148,21 +148,38 @@ func createClusterEKZ() error {
 
 	// TODO handle port clash
 	// TODO handle container name clash
-	err = getKubeconfigEKZ(containerName, expandKubeConfigFile())
-	if err != nil {
+
+	if err := getKubeconfigEKZ(containerName, expandKubeConfigFile()); err != nil {
 		return err
 	}
 	logger.Successf("kubeconfig is written to: %s", expandKubeConfigFile())
 
 	logger.Waitingf("waiting for cluster to start ...")
 	waitForNodeStarted("controller", 30*time.Second)
 
-	logger.Actionf("installing the default storageclass ...")
-	err = installDefaultStorageClass()
-	if err != nil {
+	logger.Actionf("installing the default storage class ...")
+	if err := installDefaultStorageClass(); err != nil {
 		return err
 	}
 
+	if hostMode == false {
+		bridgeName := fmt.Sprintf("ekz-%s-bridge", clusterName)
+		ipRangeVar := script.Var()
+		script.Exec("docker", "inspect", "-f", `{{range .IPAM.Config}}{{.Subnet}}{{end}}`, bridgeName).To(ipRangeVar)
+		parts := strings.SplitN(ipRangeVar.String(), ".", 4)
+		if len(parts) != 4 {
+			return errors.Errorf("error parsing subnet: %s", ipRangeVar.String())
+		}
+
+		// not vert safe range but ok to be .200-220 for a bridge subnet
+		ipRange := strings.Join(parts[0:3], ".") + ".200-" + strings.Join(parts[0:3], ".") + ".220"
+
+		logger.Actionf("installing the default load balancer using IP range: %s ...", ipRange)
+		if err := installLoadBalancer(ipRange); err != nil {
+			return err
+		}
+	}
+
 	logger.Waitingf("waiting for cluster to be ready ...")
 	waitForNodeReady(120 * time.Second)
 
@@ -173,3 +190,21 @@ func createClusterEKZ() error {
 func installDefaultStorageClass() error {
 	return script.Echo(manifests.StorageClass).Exec("kubectl", "--kubeconfig="+expandKubeConfigFile(), "apply", "-f", "-").Run()
 }
+
+func installLoadBalancer(ipRange string) error {
+	err := script.Echo(manifests.MetalLB).
+		Exec("kubectl", "--kubeconfig="+expandKubeConfigFile(), "apply", "-f", "-").
+		Run()
+	if err != nil {
+		return err
+	}
+
+	err = script.Echo(fmt.Sprintf(manifests.MetalLBConfig, ipRange)).
+		Exec("kubectl", "--kubeconfig="+expandKubeConfigFile(), "apply", "-f", "-").
+		Run()
+	if err != nil {
+		return err
+	}
+
+	return nil
+}

docs/cmd/ekz.md

@@ -54,4 +54,5 @@ All EKS-D cluster is single-node and run inside Docker.
 * [ekz get](ekz_get.md)	 - Get properties of an EKS-D cluster
 * [ekz list](ekz_list.md)	 - List clusters
 * [ekz load](ekz_load.md)	 - Load artifacts into the cluster
+* [ekz ui](ekz_ui.md)	 - Start the UI