add support for a random function

apis/v1beta1/vspheremachine_types.go

@@ -69,24 +69,25 @@ type VSphereMachineSpec struct {
 	// +optional
 	GuestSoftPowerOffTimeout *metav1.Duration `json:"guestSoftPowerOffTimeout,omitempty"`
 
-	// NamingStrategy allows configuring the naming strategy used when calculating the name of the VSphereVMs.
+	// NamingStrategy allows configuring the naming strategy used when calculating the name of the VSphereVM.
 	// +optional
 	NamingStrategy *VSphereVMNamingStrategy `json:"namingStrategy,omitempty"`
 }
 
 // VSphereVMNamingStrategy defines the naming strategy for the VSphereVMs.
 type VSphereVMNamingStrategy struct {
-	// Template defines the template to use for generating the name of the VSphereVMs object.
+	// Template defines the template to use for generating the name of the VSphereVM object.
 	// If not defined, it will fall back to `{{ .machine.name }}`.
 	// The templating has the following data available:
 	// * `.machine.name`: The name of the Machine object.
+	// * `.random`: random alphanumeric string, without vowels, of length 5
 	// The templating also has the following funcs available:
 	// * `trimSuffix`: same as strings.TrimSuffix
 	// * `trunc`: truncates a string, e.g. `trunc 2 "hello"` or `trunc -2 "hello"`
 	// Notes:
 	// * While the template offers some flexibility, we would like the name to link to the Machine name
 	//   to ensure better user experience when troubleshooting
-	// * Generated names must be valid Kubernetes names as they are used to create a VSphereVMs object
+	// * Generated names must be valid Kubernetes names as they are used to create a VSphereVM object
 	//   and usually also as the name of the Node object.
 	// * Names are automatically truncated at 63 characters. Please note that this can lead to name conflicts,
 	//   so we highly recommend to use a template which leads to a name shorter than 63 characters.

config/default/crd/bases/infrastructure.cluster.x-k8s.io_vspheremachines.yaml

@@ -1028,21 +1028,22 @@ spec:
                 type: integer
               namingStrategy:
                 description: NamingStrategy allows configuring the naming strategy
-                  used when calculating the name of the VSphereVMs.
+                  used when calculating the name of the VSphereVM.
                 properties:
                   template:
                     description: |-
-                      Template defines the template to use for generating the name of the VSphereVMs object.
+                      Template defines the template to use for generating the name of the VSphereVM object.
                       If not defined, it will fall back to `{{ .machine.name }}`.
                       The templating has the following data available:
                       * `.machine.name`: The name of the Machine object.
+                      * `.random`: random alphanumeric string, without vowels, of length 5
                       The templating also has the following funcs available:
                       * `trimSuffix`: same as strings.TrimSuffix
                       * `trunc`: truncates a string, e.g. `trunc 2 "hello"` or `trunc -2 "hello"`
                       Notes:
                       * While the template offers some flexibility, we would like the name to link to the Machine name
                         to ensure better user experience when troubleshooting
-                      * Generated names must be valid Kubernetes names as they are used to create a VSphereVMs object
+                      * Generated names must be valid Kubernetes names as they are used to create a VSphereVM object
                         and usually also as the name of the Node object.
                       * Names are automatically truncated at 63 characters. Please note that this can lead to name conflicts,
                         so we highly recommend to use a template which leads to a name shorter than 63 characters.

config/default/crd/bases/infrastructure.cluster.x-k8s.io_vspheremachinetemplates.yaml

@@ -898,21 +898,22 @@ spec:
                         type: integer
                       namingStrategy:
                         description: NamingStrategy allows configuring the naming
-                          strategy used when calculating the name of the VSphereVMs.
+                          strategy used when calculating the name of the VSphereVM.
                         properties:
                           template:
                             description: |-
-                              Template defines the template to use for generating the name of the VSphereVMs object.
+                              Template defines the template to use for generating the name of the VSphereVM object.
                               If not defined, it will fall back to `{{ .machine.name }}`.
                               The templating has the following data available:
                               * `.machine.name`: The name of the Machine object.
+                              * `.random`: random alphanumeric string, without vowels, of length 5
                               The templating also has the following funcs available:
                               * `trimSuffix`: same as strings.TrimSuffix
                               * `trunc`: truncates a string, e.g. `trunc 2 "hello"` or `trunc -2 "hello"`
                               Notes:
                               * While the template offers some flexibility, we would like the name to link to the Machine name
                                 to ensure better user experience when troubleshooting
-                              * Generated names must be valid Kubernetes names as they are used to create a VSphereVMs object
+                              * Generated names must be valid Kubernetes names as they are used to create a VSphereVM object
                                 and usually also as the name of the Node object.
                               * Names are automatically truncated at 63 characters. Please note that this can lead to name conflicts,
                                 so we highly recommend to use a template which leads to a name shorter than 63 characters.

pkg/services/vimmachine.go

@@ -38,6 +38,7 @@ import (
 	"sigs.k8s.io/controller-runtime/pkg/client"
 	ctrlutil "sigs.k8s.io/controller-runtime/pkg/controller/controllerutil"
 
+	utilrand "k8s.io/apimachinery/pkg/util/rand"
 	infrav1 "sigs.k8s.io/cluster-api-provider-vsphere/apis/v1beta1"
 	capvcontext "sigs.k8s.io/cluster-api-provider-vsphere/pkg/context"
 	infrautilv1 "sigs.k8s.io/cluster-api-provider-vsphere/pkg/util"
@@ -424,6 +425,7 @@ func generateVMObjectName(vimMachineCtx *capvcontext.VIMMachineContext, machineN
 
 const (
 	maxNameLength = 63
+	randomLength  = 5
 )
 
 // Note: Inlining these functions from sprig to avoid introducing a dependency.
@@ -456,6 +458,7 @@ func GenerateVSphereVMName(machineName string, namingStrategy *infrav1.VSphereVM
 			"name": machineName,
 		},
 	}
+	data["random"] = utilrand.String(randomLength)
 
 	tpl, err := nameTpl.Parse(nameTemplate)
 	if err != nil {