feat: enhance cloudflared connector with HPA support and resource management

pkg/controller/controlled-cloudflared-connector.go

@@ -2,7 +2,10 @@ package controller
 
 import (
 	"context"
+	"encoding/json"
 	"os"
+	"reflect"
+	"slices"
 	"strconv"
 
 	cloudflarecontroller "github.com/STRRL/cloudflare-tunnel-ingress-controller/pkg/cloudflare-controller"
@@ -24,14 +27,15 @@ func CreateOrUpdateControlledCloudflared(
 	extraArgs []string,
 ) error {
 	logger := log.FromContext(ctx)
-	list := appsv1.DeploymentList{}
-	err := kubeClient.List(ctx, &list, &client.ListOptions{
+
+	// List existing deployments with the specific label
+	var list appsv1.DeploymentList
+	if err := kubeClient.List(ctx, &list, &client.ListOptions{
 		Namespace: namespace,
 		LabelSelector: labels.SelectorFromSet(labels.Set{
 			"strrl.dev/cloudflare-tunnel-ingress-controller": "controlled-cloudflared-connector",
 		}),
-	})
-	if err != nil {
+	}); err != nil {
 		return errors.Wrapf(err, "list controlled-cloudflared-connector in namespace %s", namespace)
 	}
 
@@ -44,7 +48,7 @@ func CreateOrUpdateControlledCloudflared(
 		}
 
 		needsUpdate := false
-		if *existingDeployment.Spec.Replicas != desiredReplicas {
+		if desiredReplicas >= 0 && existingDeployment.Spec.Replicas != nil && *existingDeployment.Spec.Replicas != desiredReplicas {
 			needsUpdate = true
 		}
 
@@ -55,27 +59,34 @@ func CreateOrUpdateControlledCloudflared(
 		}
 
 		if len(existingDeployment.Spec.Template.Spec.Containers) > 0 {
-			container := &existingDeployment.Spec.Template.Spec.Containers[0]
+			container := existingDeployment.Spec.Template.Spec.Containers[0]
 			if container.Image != os.Getenv("CLOUDFLARED_IMAGE") {
 				needsUpdate = true
 			}
 			if string(container.ImagePullPolicy) != os.Getenv("CLOUDFLARED_IMAGE_PULL_POLICY") {
 				needsUpdate = true
 			}
-			
+
 			// Check if command arguments have changed
-			desiredCommand := buildCloudflaredCommand(protocol, token, extraArgs)
-			if !slicesEqual(container.Command, desiredCommand) {
+			desiredCommand := getCloudflaredCommand(protocol, token, extraArgs)
+			if !slices.Equal(container.Command, desiredCommand) {
+				needsUpdate = true
+			}
+
+			// Check if resource requirements have changed
+			desiredResources, err := getDesiredResources()
+			if err != nil {
+				return errors.Wrap(err, "get desired resources")
+			}
+			if os.Getenv("CLOUDFLARED_RESOURCES") != "" && !reflect.DeepEqual(container.Resources, desiredResources) {
 				needsUpdate = true
 			}
 		}
 
 		if needsUpdate {
-
 			updatedDeployment := cloudflaredConnectDeploymentTemplating(protocol, token, namespace, desiredReplicas, extraArgs)
 			existingDeployment.Spec = updatedDeployment.Spec
-			err = kubeClient.Update(ctx, existingDeployment)
-			if err != nil {
+			if err := kubeClient.Update(ctx, existingDeployment); err != nil {
 				return errors.Wrap(err, "update controlled-cloudflared-connector deployment")
 			}
 			logger.Info("Updated controlled-cloudflared-connector deployment", "namespace", namespace)
@@ -95,11 +106,11 @@ func CreateOrUpdateControlledCloudflared(
 	}
 
 	deployment := cloudflaredConnectDeploymentTemplating(protocol, token, namespace, replicas, extraArgs)
-	err = kubeClient.Create(ctx, deployment)
-	if err != nil {
+	if err := kubeClient.Create(ctx, deployment); err != nil {
 		return errors.Wrap(err, "create controlled-cloudflared-connector deployment")
 	}
 	logger.Info("Created controlled-cloudflared-connector deployment", "namespace", namespace)
+
 	return nil
 }
 
@@ -117,7 +128,10 @@ func cloudflaredConnectDeploymentTemplating(protocol string, token string, names
 		pullPolicy = "IfNotPresent"
 	}
 
-	return &appsv1.Deployment{
+	// Ignore error, if any. If there's an error, resources will be empty and thus ignored by Kubernetes.
+	resources, _ := getDesiredResources()
+
+	deployment := &appsv1.Deployment{
 		ObjectMeta: metav1.ObjectMeta{
 			Name:      appName,
 			Namespace: namespace,
@@ -148,20 +162,27 @@ func cloudflaredConnectDeploymentTemplating(protocol string, token string, names
 							Name:            appName,
 							Image:           image,
 							ImagePullPolicy: v1.PullPolicy(pullPolicy),
-							Command: buildCloudflaredCommand(protocol, token, extraArgs),
+							Command:         getCloudflaredCommand(protocol, token, extraArgs),
+							Resources:       resources,
 						},
 					},
 					RestartPolicy: v1.RestartPolicyAlways,
 				},
 			},
 		},
 	}
+
+	if replicas < 0 {
+		deployment.Spec.Replicas = nil // Use Kubernetes default
+	}
+
+	return deployment
 }
 
 func getDesiredReplicas() (int32, error) {
 	replicaCount := os.Getenv("CLOUDFLARED_REPLICA_COUNT")
 	if replicaCount == "" {
-		return 1, nil
+		return -1, nil
 	}
 	replicas, err := strconv.ParseInt(replicaCount, 10, 32)
 	if err != nil {
@@ -170,34 +191,37 @@ func getDesiredReplicas() (int32, error) {
 	return int32(replicas), nil
 }
 
-func buildCloudflaredCommand(protocol string, token string, extraArgs []string) []string {
+func getCloudflaredCommand(protocol string, token string, extraArgs []string) []string {
 	command := []string{
 		"cloudflared",
 		"--protocol",
 		protocol,
 		"--no-autoupdate",
 		"tunnel",
 	}
-	
+
 	// Add all extra arguments between "tunnel" and "run"
 	if len(extraArgs) > 0 {
 		command = append(command, extraArgs...)
 	}
-	
+
 	// Add metrics, run subcommand and token
 	command = append(command, "--metrics", "0.0.0.0:44483", "run", "--token", token)
-	
+
 	return command
 }
 
-func slicesEqual(a, b []string) bool {
-	if len(a) != len(b) {
-		return false
+func getDesiredResources() (v1.ResourceRequirements, error) {
+	var desiredresources v1.ResourceRequirements
+
+	resources := os.Getenv("CLOUDFLARED_RESOURCES")
+	if resources == "" {
+		return desiredresources, nil
 	}
-	for i, v := range a {
-		if v != b[i] {
-			return false
-		}
+
+	if err := json.Unmarshal([]byte(resources), &desiredresources); err != nil {
+		return desiredresources, errors.Wrap(err, "invalid resource requirements")
 	}
-	return true
+
+	return desiredresources, nil
 }

pkg/controller/controlled-cloudflared-connector_test.go

@@ -6,7 +6,7 @@ import (
 	"github.com/stretchr/testify/assert"
 )
 
-func TestBuildCloudflaredCommand(t *testing.T) {
+func TestGetCloudflaredCommand(t *testing.T) {
 	tests := []struct {
 		name      string
 		protocol  string
@@ -94,61 +94,8 @@ func TestBuildCloudflaredCommand(t *testing.T) {
 
 	for _, tt := range tests {
 		t.Run(tt.name, func(t *testing.T) {
-			result := buildCloudflaredCommand(tt.protocol, tt.token, tt.extraArgs)
+			result := getCloudflaredCommand(tt.protocol, tt.token, tt.extraArgs)
 			assert.Equal(t, tt.expected, result)
 		})
 	}
 }
-
-func TestSlicesEqual(t *testing.T) {
-	tests := []struct {
-		name     string
-		a        []string
-		b        []string
-		expected bool
-	}{
-		{
-			name:     "equal slices",
-			a:        []string{"a", "b", "c"},
-			b:        []string{"a", "b", "c"},
-			expected: true,
-		},
-		{
-			name:     "different length",
-			a:        []string{"a", "b"},
-			b:        []string{"a", "b", "c"},
-			expected: false,
-		},
-		{
-			name:     "different content",
-			a:        []string{"a", "b", "c"},
-			b:        []string{"a", "x", "c"},
-			expected: false,
-		},
-		{
-			name:     "empty slices",
-			a:        []string{},
-			b:        []string{},
-			expected: true,
-		},
-		{
-			name:     "nil slices",
-			a:        nil,
-			b:        nil,
-			expected: true,
-		},
-		{
-			name:     "nil vs empty",
-			a:        nil,
-			b:        []string{},
-			expected: true,
-		},
-	}
-
-	for _, tt := range tests {
-		t.Run(tt.name, func(t *testing.T) {
-			result := slicesEqual(tt.a, tt.b)
-			assert.Equal(t, tt.expected, result)
-		})
-	}
-}