Add support for specifying vsphere credentials via secrets (#250)

- Adds new field vsphereCredentialSecret that can be specified to
  point to the secret that holds the credentials

Resolves #9

Change-Id: I8e43864302a51386f7f11725b0a966cc9e436c59

cmd/clusterctl/examples/vsphere/cluster.yaml.template

@@ -15,4 +15,5 @@ spec:
         kind: "VsphereClusterProviderConfig"
         vsphereUser: ""
         vspherePassword: ""
-        vsphereServer: ""
+        vsphereServer: ""
+        vsphereCredentialSecret: ""

docs/design/vsphereCredentials.md

@@ -0,0 +1,49 @@
+## Passing vsphere credentials
+For the cluster-api vsphere provider to work, the users need to provide the vsphere credentials to access the infrastructure. There are 2 ways how the users can provide these credentials.
+
+* Using kubernetes `secrets`
+   * Create a secret that contains 2 keys namely `username` and `password` in the same namespace as the desired `Cluster` object.
+      ```
+      apiVersion: v1
+      kind: Secret
+      metadata:
+        name: my-vc-credentials
+      type: Opaque
+      data:
+        # base64 encoded fields
+        username: YWRtaW5pc3RyYXRvckB2c3BoZXJlLmxvY2Fs
+        password: c2FtcGxl
+      ```
+
+   * Set the `vsphereCredentialSecret` property in the `ProviderSpec` part of the `Cluster` definition
+      ```
+      apiVersion: "cluster.k8s.io/v1alpha1"
+      kind: Cluster
+      metadata:
+        name: sample-cluster
+      spec:
+          ...
+          providerSpec:
+            value:
+              ...
+              # Credentials provided via secrets
+              vsphereCredentialSecret: "my-vc-credentials"
+      ```
+
+* Using plain text credential in the `ProviderSpec` part of the `Cluster` definition
+    ```
+    apiVersion: "cluster.k8s.io/v1alpha1"
+    kind: Cluster
+    metadata:
+      name: sample-cluster
+    spec:
+        ...
+        providerSpec:
+          value:
+            ...
+            # Credentials provided as plain text
+            vsphereUser: "administrator@vsphere.local"
+            vspherePassword: "sample"
+    ```
+
+__Note:__ If `vsphereCredentialSecret` field is set to a non empty string then the controller will ignore the `vsphereUser` and `vspherePassword` fields even if they are set.

pkg/apis/vsphereproviderconfig/v1alpha1/vsphereclusterproviderconfig_types.go

@@ -47,9 +47,10 @@ type VsphereClusterProviderConfig struct {
 	metav1.TypeMeta   `json:",inline"`
 	metav1.ObjectMeta `json:"metadata,omitempty"`
 
-	VsphereUser     string `json:"vsphereUser"`
-	VspherePassword string `json:"vspherePassword"`
-	VsphereServer   string `json:"vsphereServer"`
+	VsphereUser             string `json:"vsphereUser"`
+	VspherePassword         string `json:"vspherePassword"`
+	VsphereServer           string `json:"vsphereServer"`
+	VsphereCredentialSecret string `json:"vsphereCredentialSecret"`
 }
 
 // +k8s:deepcopy-gen:interfaces=k8s.io/apimachinery/pkg/runtime.Object

pkg/cloud/vsphere/constants/constants.go

@@ -20,5 +20,7 @@ const (
 	RequeueAfterSeconds              = 20 * time.Second
 	KubeConfigSecretName             = "%s-kubeconfig"
 	KubeConfigSecretData             = "admin-kubeconfig"
+	VsphereUserKey                   = "username"
+	VspherePasswordKey               = "password"
 	ClusterIsNullErr                 = "cluster is nil, make sure machines have `clusters.k8s.io/cluster-name` label set and the name references a valid cluster name in the same namespace"
 )

pkg/cloud/vsphere/provisioner/govmomi/session.go

@@ -25,7 +25,11 @@ func (pv *Provisioner) sessionFromProviderConfig(cluster *clusterv1.Cluster, mac
 	if err != nil {
 		return nil, err
 	}
-	if ses, ok := pv.sessioncache[vsphereConfig.VsphereServer+vsphereConfig.VsphereUser]; ok {
+	username, password, err := pv.GetVsphereCredentials(cluster)
+	if err != nil {
+		return nil, err
+	}
+	if ses, ok := pv.sessioncache[vsphereConfig.VsphereServer+username]; ok {
 		s, ok := ses.(SessionContext)
 		if ok {
 			// Test if the session is valid and return
@@ -41,7 +45,7 @@ func (pv *Provisioner) sessionFromProviderConfig(cluster *clusterv1.Cluster, mac
 		return nil, fmt.Errorf("error parsing vSphere URL %s : [%s]", soapURL, err)
 	}
 	// Set the credentials
-	soapURL.User = url.UserPassword(vsphereConfig.VsphereUser, vsphereConfig.VspherePassword)
+	soapURL.User = url.UserPassword(username, password)
 	// Temporarily setting the insecure flag True
 	// TODO(ssurana): handle the certs better
 	sc.session, err = govmomi.NewClient(ctx, soapURL, true)
@@ -51,6 +55,6 @@ func (pv *Provisioner) sessionFromProviderConfig(cluster *clusterv1.Cluster, mac
 	sc.context = &ctx
 	finder := find.NewFinder(sc.session.Client, false)
 	sc.finder = finder
-	pv.sessioncache[vsphereConfig.VsphereServer+vsphereConfig.VsphereUser] = sc
+	pv.sessioncache[vsphereConfig.VsphereServer+username] = sc
 	return &sc, nil
 }

pkg/cloud/vsphere/provisioner/govmomi/utils.go

@@ -190,3 +190,27 @@ func (pv *Provisioner) GetKubeConfig(cluster *clusterv1.Cluster) (string, error)
 	}
 	return string(secret.Data[constants.KubeConfigSecretData]), nil
 }
+
+func (pv *Provisioner) GetVsphereCredentials(cluster *clusterv1.Cluster) (string, string, error) {
+	vsphereConfig, err := vsphereutils.GetClusterProviderSpec(cluster.Spec.ProviderSpec)
+	if err != nil {
+		return "", "", err
+	}
+	// If the vsphereCredentialSecret is specified then read that secret to get the credentials
+	if vsphereConfig.VsphereCredentialSecret != "" {
+		klog.V(4).Infof("Fetching vsphere credentials from secret %s", vsphereConfig.VsphereCredentialSecret)
+		secret, err := pv.k8sClient.Core().Secrets(cluster.Namespace).Get(vsphereConfig.VsphereCredentialSecret, metav1.GetOptions{})
+		if err != nil {
+			klog.Warningf("Error reading secret %s", vsphereConfig.VsphereCredentialSecret)
+			return "", "", err
+		}
+		if username, ok := secret.Data[constants.VsphereUserKey]; ok {
+			if password, ok := secret.Data[constants.VspherePasswordKey]; ok {
+				return string(username), string(password), nil
+			}
+		}
+		return "", "", fmt.Errorf("Improper secret: Secret %s should have the keys `%s` and `%s` defined in it", vsphereConfig.VsphereCredentialSecret, constants.VsphereUserKey, constants.VspherePasswordKey)
+	}
+	return vsphereConfig.VsphereUser, vsphereConfig.VspherePassword, nil
+
+}