[feat]: Add custom prefix for load balancer (#414)

* [feat]: Add custom prefix for load balancer

* Update function for naming loadbalacer

* Add limit error for prefix

* Add dash after prefix

* Change name of flag to nodebalacer-prefix

* Add flag to helm chart

* Remove hardocoded string

* Fix tests

* Update NodeBalancerPrefixCharLimit

* Replace assert to require

* Cover empty string case

* Prefix validation

* Update tests

---------

Co-authored-by: Rahul Sharma <[email protected]>

Author: adamginna-akamai

cloud/linode/cloud.go

@@ -8,6 +8,7 @@ import (
 	"os"
 	"strconv"
 	"time"
+	"regexp"
 
 	"github.com/spf13/pflag"
 	"golang.org/x/exp/slices"
@@ -58,6 +59,7 @@ var Options struct {
 	ClusterCIDRIPv4                   string
 	NodeCIDRMaskSizeIPv4              int
 	NodeCIDRMaskSizeIPv6              int
+	NodeBalancerPrefix                string
 }
 
 type linodeCloud struct {
@@ -69,8 +71,9 @@ type linodeCloud struct {
 }
 
 var (
-	instanceCache     *instances
-	ipHolderCharLimit int = 23
+	instanceCache               *instances
+	ipHolderCharLimit           int = 23
+	NodeBalancerPrefixCharLimit int = 19
 )
 
 func init() {
@@ -193,6 +196,19 @@ func newCloud() (cloudprovider.Interface, error) {
 		return nil, fmt.Errorf("%s", msg)
 	}
 
+	if len(Options.NodeBalancerPrefix) > NodeBalancerPrefixCharLimit {
+		msg := fmt.Sprintf("nodebalancer-prefix must be %d characters or less: %s is %d characters\n", NodeBalancerPrefixCharLimit, Options.NodeBalancerPrefix, len(Options.NodeBalancerPrefix))
+		klog.Error(msg)
+		return nil, fmt.Errorf("%s", msg)
+	}
+
+	validPrefix := regexp.MustCompile(`^[a-zA-Z0-9_-]+$`)
+	if !validPrefix.MatchString(Options.NodeBalancerPrefix) {
+		msg := fmt.Sprintf("nodebalancer-prefix must be no empty and use only letters, numbers, underscores, and dashes: %s\n", Options.NodeBalancerPrefix)
+		klog.Error(msg)
+		return nil, fmt.Errorf("%s", msg)
+	}
+
 	// create struct that satisfies cloudprovider.Interface
 	lcloud := &linodeCloud{
 		client:                   linodeClient,

cloud/linode/cloud_test.go

@@ -20,6 +20,7 @@ func TestNewCloudRouteControllerDisabled(t *testing.T) {
 	t.Setenv("LINODE_API_TOKEN", "dummyapitoken")
 	t.Setenv("LINODE_REGION", "us-east")
 	t.Setenv("LINODE_REQUEST_TIMEOUT_SECONDS", "10")
+	Options.NodeBalancerPrefix = "ccm"
 
 	t.Run("should not fail if vpc is empty and routecontroller is disabled", func(t *testing.T) {
 		Options.VPCName = ""
@@ -45,6 +46,7 @@ func TestNewCloud(t *testing.T) {
 	t.Setenv("LINODE_REQUEST_TIMEOUT_SECONDS", "10")
 	t.Setenv("LINODE_ROUTES_CACHE_TTL_SECONDS", "60")
 	Options.LinodeGoDebug = true
+	Options.NodeBalancerPrefix = "ccm"
 
 	t.Run("should fail if api token is empty", func(t *testing.T) {
 		t.Setenv("LINODE_API_TOKEN", "")
@@ -126,6 +128,57 @@ func TestNewCloud(t *testing.T) {
 		_, err := newCloud()
 		assert.Error(t, err, "expected error if ipholdersuffix is longer than 23 chars")
 	})
+
+	t.Run("should fail if nodebalancer-prefix is longer than 19 chars", func(t *testing.T) {
+		prefix := Options.NodeBalancerPrefix
+		rtEnabled := Options.EnableRouteController
+		Options.EnableRouteController = false
+		Options.LoadBalancerType = "nodebalancer"
+		Options.NodeBalancerPrefix = strings.Repeat("a", 21)
+		defer func() {
+			Options.NodeBalancerPrefix = prefix
+			Options.LoadBalancerType = ""
+			Options.EnableRouteController = rtEnabled
+		}()
+		_, err := newCloud()
+		t.Log(err)
+		require.Error(t, err, "expected error if nodebalancer-prefix is longer than 19 chars")
+		require.ErrorContains(t, err, "nodebalancer-prefix")
+	})
+
+	t.Run("should fail if nodebalancer-prefix is empty", func(t *testing.T) {
+		prefix := Options.NodeBalancerPrefix
+		rtEnabled := Options.EnableRouteController
+		Options.EnableRouteController = false
+		Options.LoadBalancerType = "nodebalancer"
+		Options.NodeBalancerPrefix = ""
+		defer func() {
+			Options.NodeBalancerPrefix = prefix
+			Options.LoadBalancerType = ""
+			Options.EnableRouteController = rtEnabled
+		}()
+		_, err := newCloud()
+		t.Log(err)
+		require.Error(t, err, "expected error if nodebalancer-prefix is empty")
+		require.ErrorContains(t, err, "nodebalancer-prefix must be no empty")
+	})
+
+	t.Run("should fail if not validated nodebalancer-prefix", func(t *testing.T) {
+		prefix := Options.NodeBalancerPrefix
+		rtEnabled := Options.EnableRouteController
+		Options.EnableRouteController = false
+		Options.LoadBalancerType = "nodebalancer"
+		Options.NodeBalancerPrefix = "\\+x"
+		defer func() {
+			Options.NodeBalancerPrefix = prefix
+			Options.LoadBalancerType = ""
+			Options.EnableRouteController = rtEnabled
+		}()
+		_, err := newCloud()
+		t.Log(err)
+		require.Error(t, err, "expected error if not validated nodebalancer-prefix")
+		require.ErrorContains(t, err, "nodebalancer-prefix must be no empty and use only letters, numbers, underscores, and dashes")
+	})
 }
 
 func Test_linodeCloud_LoadBalancer(t *testing.T) {

cloud/linode/loadbalancers.go

@@ -227,7 +227,7 @@ func (l *loadbalancers) cleanupOldNodeBalancer(ctx context.Context, service *v1.
 // GetLoadBalancer will not modify service.
 func (l *loadbalancers) GetLoadBalancerName(_ context.Context, _ string, _ *v1.Service) string {
 	unixNano := strconv.FormatInt(time.Now().UnixNano(), 16)
-	return fmt.Sprintf("ccm-%s", unixNano[len(unixNano)-12:])
+	return fmt.Sprintf("%s-%s", Options.NodeBalancerPrefix, unixNano[len(unixNano)-12:])
 }
 
 // GetLoadBalancer returns the *v1.LoadBalancerStatus of service.

deploy/chart/templates/daemonset.yaml

@@ -156,6 +156,9 @@ spec:
             {{- if .Values.nodeBalancerBackendIPv4Subnet }}
             - --nodebalancer-backend-ipv4-subnet={{ .Values.nodeBalancerBackendIPv4Subnet }}
             {{- end }}
+            {{- if .Values.nodeBalancerPrefix }}
+            - --nodebalancer-prefix={{ .Values.nodeBalancerPrefix }}
+            {{- end }}
             {{- if .Values.extraArgs }}
             {{- toYaml .Values.extraArgs | nindent 12 }}
             {{- end }}

deploy/chart/values.yaml

@@ -116,6 +116,9 @@ tolerations:
 # nodeBalancerBackendIPv4SubnetName is the subnet name to use for the backend ips of the NodeBalancer
 # nodeBalancerBackendIPv4SubnetName: ""
 
+# nodeBalancerPrefix is used to add prefix for nodeBalancer name. Default is "ccm"
+# nodeBalancerPrefix: ""
+
 # This section adds the ability to pass environment variables to adjust CCM defaults
 # https://github.com/linode/linode-cloud-controller-manager/blob/master/cloud/linode/loadbalancers.go
 # LINODE_HOSTNAME_ONLY_INGRESS type bool is supported

docs/configuration/environment.md

@@ -53,6 +53,7 @@ The CCM supports the following flags:
 | `--enable-ipv6-for-loadbalancers` | `false` | Set both IPv4 and IPv6 addresses for all LoadBalancer services (when disabled, only IPv4 is used). This can also be configured per-service using the `service.beta.kubernetes.io/linode-loadbalancer-enable-ipv6-ingress` annotation. |
 | `--node-cidr-mask-size-ipv4` | `24` | ipv4 cidr mask size for pod cidrs allocated to nodes |
 | `--node-cidr-mask-size-ipv6` | `64` | ipv6 cidr mask size for pod cidrs allocated to nodes |
+| `--nodebalancer-prefix` | `ccm` | Name prefix for NoadBalancers. |
 
 ## Configuration Methods
 

main.go

@@ -98,6 +98,7 @@ func main() {
 	command.Flags().IntVar(&linode.Options.NodeBalancerBackendIPv4SubnetID, "nodebalancer-backend-ipv4-subnet-id", 0, "ipv4 subnet id to use for NodeBalancer backends")
 	command.Flags().StringVar(&linode.Options.NodeBalancerBackendIPv4SubnetName, "nodebalancer-backend-ipv4-subnet-name", "", "ipv4 subnet name to use for NodeBalancer backends")
 	command.Flags().BoolVar(&linode.Options.DisableNodeBalancerVPCBackends, "disable-nodebalancer-vpc-backends", false, "disables nodebalancer backends in VPCs (when enabled, nodebalancers will only have private IPs as backends for backward compatibility)")
+	command.Flags().StringVar(&linode.Options.NodeBalancerPrefix, "nodebalancer-prefix", "ccm", fmt.Sprintf("Name prefix for NoadBalancers. (max. %v char.)", linode.NodeBalancerPrefixCharLimit))
 
 	// Set static flags
 	command.Flags().VisitAll(func(fl *pflag.Flag) {