Use pointers for ng.(DesiredCapacity|MinSize|MaxSize)

pkg/apis/eksctl.io/v1alpha4/types.go

@@ -288,7 +288,7 @@ func (c *ClusterConfig) NewNodeGroup() *NodeGroup {
 			WithLocal:  NewBoolTrue(),
 			WithShared: NewBoolTrue(),
 		},
-		DesiredCapacity: DefaultNodeCount,
+		DesiredCapacity: nil,
 		InstanceType:    DefaultNodeType,
 		VolumeSize:      0,
 		VolumeType:      DefaultNodeVolumeType,
@@ -327,11 +327,11 @@ type NodeGroup struct {
 	SecurityGroups *NodeGroupSGs `json:"securityGroups,omitempty"`
 
 	// +optional
-	DesiredCapacity int `json:"desiredCapacity"`
+	DesiredCapacity *int `json:"desiredCapacity"`
 	// +optional
-	MinSize int `json:"minSize,omitempty"`
+	MinSize *int `json:"minSize,omitempty"`
 	// +optional
-	MaxSize int `json:"maxSize,omitempty"`
+	MaxSize *int `json:"maxSize,omitempty"`
 
 	// +optional
 	VolumeSize int `json:"volumeSize"`

pkg/cfn/builder/api_test.go

@@ -308,7 +308,7 @@ var _ = Describe("CloudFormation template builder API", func() {
 						WithShared: api.NewBoolTrue(),
 						AttachIDs:  []string{},
 					},
-					DesiredCapacity: 2,
+					DesiredCapacity: nil,
 					VolumeSize:      2,
 					VolumeType:      api.NodeVolumeTypeIO1,
 					IAM: &api.NodeGroupIAM{

pkg/cfn/builder/nodegroup.go

@@ -59,25 +59,28 @@ func (n *NodeGroupResourceSet) AddAllResources() error {
 	}
 	n.userData = gfn.NewString(userData)
 
-	switch {
-	case n.spec.MinSize == 0 && n.spec.MaxSize == 0:
-		n.spec.MinSize = n.spec.DesiredCapacity
-		n.spec.MaxSize = n.spec.DesiredCapacity
-	case n.spec.MinSize > 0 && n.spec.MaxSize > 0:
-		if n.spec.DesiredCapacity == api.DefaultNodeCount {
-			msgPrefix := fmt.Sprintf("as --nodes-min=%d and --nodes-max=%d were given", n.spec.MinSize, n.spec.MaxSize)
-			if n.spec.DesiredCapacity < n.spec.MinSize {
-				n.spec.DesiredCapacity = n.spec.MaxSize
-				logger.Info("%s, --nodes=%d was set automatically as default value (--node=%d) was outside the set renge",
-					msgPrefix, n.spec.DesiredCapacity, api.DefaultNodeCount)
-			} else {
-				logger.Info("%s, default value of --nodes=%d was kept as it is within the set range",
-					msgPrefix, n.spec.DesiredCapacity)
-			}
+	// Ensure MinSize is set, as it is required by the ASG cfn resource
+	if n.spec.MinSize == nil {
+		if n.spec.DesiredCapacity == nil {
+			count := api.DefaultNodeCount
+			n.spec.MinSize = &count
+			logger.Info("--nodes-min=%d was set automatically", count)
+		} else {
+			n.spec.MinSize = n.spec.DesiredCapacity
 		}
-		if n.spec.DesiredCapacity > n.spec.MaxSize {
-			return fmt.Errorf("cannot use --nodes-max=%d and --nodes=%d at the same time", n.spec.MaxSize, n.spec.DesiredCapacity)
+	} else if n.spec.DesiredCapacity != nil && *n.spec.DesiredCapacity < *n.spec.MinSize {
+		return fmt.Errorf("cannot use --nodes-min=%d and --nodes=%d at the same time", *n.spec.MinSize, *n.spec.DesiredCapacity)
+	}
+
+	// Ensure MaxSize is set, as it is required by the ASG cfn resource
+	if n.spec.MaxSize == nil {
+		if n.spec.DesiredCapacity == nil {
+			n.spec.MaxSize = n.spec.MinSize
 		}
+	} else if n.spec.DesiredCapacity != nil && *n.spec.DesiredCapacity > *n.spec.MaxSize {
+		return fmt.Errorf("cannot use --nodes-max=%d and --nodes=%d at the same time", *n.spec.MaxSize, *n.spec.DesiredCapacity)
+	} else if *n.spec.MaxSize < *n.spec.MinSize {
+		return fmt.Errorf("cannot use --nodes-min=%d and --nodes-max=%d at the same time", *n.spec.MinSize, *n.spec.MaxSize)
 	}
 
 	n.addResourcesForIAM()
@@ -179,16 +182,23 @@ func (n *NodeGroupResourceSet) addResourcesForNodeGroup() error {
 			},
 		)
 	}
+	ngProps := map[string]interface{}{
+		"LaunchConfigurationName": refLC,
+		"VPCZoneIdentifier":       vpcZoneIdentifier,
+		"Tags":                    tags,
+	}
+	if n.spec.DesiredCapacity != nil {
+		ngProps["DesiredCapacity"] = fmt.Sprintf("%d", *n.spec.DesiredCapacity)
+	}
+	if n.spec.MinSize != nil {
+		ngProps["MinSize"] = fmt.Sprintf("%d", *n.spec.MinSize)
+	}
+	if n.spec.MaxSize != nil {
+		ngProps["MaxSize"] = fmt.Sprintf("%d", *n.spec.MaxSize)
+	}
 	n.newResource("NodeGroup", &awsCloudFormationResource{
-		Type: "AWS::AutoScaling::AutoScalingGroup",
-		Properties: map[string]interface{}{
-			"LaunchConfigurationName": refLC,
-			"DesiredCapacity":         fmt.Sprintf("%d", n.spec.DesiredCapacity),
-			"MinSize":                 fmt.Sprintf("%d", n.spec.MinSize),
-			"MaxSize":                 fmt.Sprintf("%d", n.spec.MaxSize),
-			"VPCZoneIdentifier":       vpcZoneIdentifier,
-			"Tags":                    tags,
-		},
+		Type:       "AWS::AutoScaling::AutoScalingGroup",
+		Properties: ngProps,
 		UpdatePolicy: map[string]map[string]string{
 			"AutoScalingRollingUpdate": {
 				"MinInstancesInService": "1",

pkg/cfn/manager/nodegroup.go

@@ -157,7 +157,7 @@ func (c *StackCollection) ScaleNodeGroup(ng *api.NodeGroup) error {
 	currentMaxSize := gjson.Get(template, maxSizePath)
 	currentMinSize := gjson.Get(template, minSizePath)
 
-	if int64(ng.DesiredCapacity) == currentCapacity.Int() {
+	if ng.DesiredCapacity != nil && int64(*ng.DesiredCapacity) == currentCapacity.Int() {
 		logger.Info("desired capacity of nodegroup %q in cluster %q is already %d", ng.Name, clusterName, ng.DesiredCapacity)
 		return nil
 	}
@@ -171,7 +171,7 @@ func (c *StackCollection) ScaleNodeGroup(ng *api.NodeGroup) error {
 	descriptionBuffer.WriteString(fmt.Sprintf("desired capacity from %s to %d", currentCapacity.Str, ng.DesiredCapacity))
 
 	// If the desired number of nodes is less than the min then update the min
-	if int64(ng.DesiredCapacity) < currentMinSize.Int() {
+	if int64(*ng.DesiredCapacity) < currentMinSize.Int() {
 		newMinSize := fmt.Sprintf("%d", ng.DesiredCapacity)
 		template, err = sjson.Set(template, minSizePath, newMinSize)
 		if err != nil {
@@ -180,7 +180,7 @@ func (c *StackCollection) ScaleNodeGroup(ng *api.NodeGroup) error {
 		descriptionBuffer.WriteString(fmt.Sprintf(", min size from %s to %d", currentMinSize.Str, ng.DesiredCapacity))
 	}
 	// If the desired number of nodes is greater than the max then update the max
-	if int64(ng.DesiredCapacity) > currentMaxSize.Int() {
+	if int64(*ng.DesiredCapacity) > currentMaxSize.Int() {
 		newMaxSize := fmt.Sprintf("%d", ng.DesiredCapacity)
 		template, err = sjson.Set(template, maxSizePath, newMaxSize)
 		if err != nil {

pkg/cfn/manager/nodegroup_test.go

@@ -76,7 +76,8 @@ var _ = Describe("StackCollection NodeGroup", func() {
 
 			It("should be a no-op if attempting to scale to the existing desired capacity", func() {
 				ng.Name = "12345"
-				ng.DesiredCapacity = 2
+				cap := 2
+				ng.DesiredCapacity = &cap
 
 				err := sc.ScaleNodeGroup(ng)
 

pkg/ctl/cmdutils/nodegroup.go

@@ -4,6 +4,7 @@ import (
 	"fmt"
 	"strings"
 
+	"github.com/spf13/cobra"
 	"github.com/spf13/pflag"
 
 	"github.com/weaveworks/eksctl/pkg/ami"
@@ -16,13 +17,29 @@ const (
 )
 
 // AddCommonCreateNodeGroupFlags adds common flags for creating a node group
-func AddCommonCreateNodeGroupFlags(fs *pflag.FlagSet, p *api.ProviderConfig, cfg *api.ClusterConfig, ng *api.NodeGroup) {
+func AddCommonCreateNodeGroupFlags(cmd *cobra.Command, fs *pflag.FlagSet, p *api.ProviderConfig, cfg *api.ClusterConfig, ng *api.NodeGroup) {
+	var desiredCapacity int
+	var minSize int
+	var maxSize int
+
 	fs.StringVarP(&ng.InstanceType, "node-type", "t", defaultNodeType, "node instance type")
-	fs.IntVarP(&ng.DesiredCapacity, "nodes", "N", api.DefaultNodeCount, "total number of nodes (for a static ASG)")
+	fs.IntVarP(&desiredCapacity, "nodes", "N", api.DefaultNodeCount, "total number of nodes (for a static ASG)")
 
 	// TODO: https://github.com/weaveworks/eksctl/issues/28
-	fs.IntVarP(&ng.MinSize, "nodes-min", "m", 0, "minimum nodes in ASG")
-	fs.IntVarP(&ng.MaxSize, "nodes-max", "M", 0, "maximum nodes in ASG")
+	fs.IntVarP(&minSize, "nodes-min", "m", api.DefaultNodeCount, "minimum nodes in ASG")
+	fs.IntVarP(&maxSize, "nodes-max", "M", api.DefaultNodeCount, "maximum nodes in ASG")
+
+	cmd.PreRun = func(cmd *cobra.Command, args[] string) {
+		if f := cmd.Flag("nodes"); f.Changed {
+			ng.DesiredCapacity = &desiredCapacity
+		}
+		if f := cmd.Flag("nodes-min"); f.Changed {
+			ng.MinSize= &minSize
+		}
+		if f := cmd.Flag("nodes-max"); f.Changed {
+			ng.MaxSize= &maxSize
+		}
+	}
 
 	fs.IntVar(&ng.VolumeSize, "node-volume-size", ng.VolumeSize, "node volume size in GB")
 	fs.StringVar(&ng.VolumeType, "node-volume-type", ng.VolumeType, fmt.Sprintf("node volume type (valid options: %s)", strings.Join(api.SupportedNodeVolumeTypes(), ", ")))

pkg/ctl/create/cluster.go

@@ -73,7 +73,7 @@ func createClusterCmd(g *cmdutils.Grouping) *cobra.Command {
 	group.InFlagSet("Initial nodegroup", func(fs *pflag.FlagSet) {
 		fs.StringVar(&ng.Name, "nodegroup-name", "", fmt.Sprintf("name of the nodegroup (generated if unspecified, e.g. %q)", exampleNodeGroupName))
 		fs.BoolVar(&withoutNodeGroup, "without-nodegroup", false, "if set, initial nodegroup will not be created")
-		cmdutils.AddCommonCreateNodeGroupFlags(fs, p, cfg, ng)
+		cmdutils.AddCommonCreateNodeGroupFlags(cmd, fs, p, cfg, ng)
 	})
 
 	group.InFlagSet("Cluster and nodegroup add-ons", func(fs *pflag.FlagSet) {

pkg/ctl/create/nodegroup.go

@@ -44,7 +44,7 @@ func createNodeGroupCmd(g *cmdutils.Grouping) *cobra.Command {
 
 	group.InFlagSet("New nodegroup", func(fs *pflag.FlagSet) {
 		fs.StringVarP(&ng.Name, "name", "n", "", fmt.Sprintf("name of the new nodegroup (generated if unspecified, e.g. %q)", exampleNodeGroupName))
-		cmdutils.AddCommonCreateNodeGroupFlags(fs, p, cfg, ng)
+		cmdutils.AddCommonCreateNodeGroupFlags(cmd, fs, p, cfg, ng)
 	})
 
 	group.InFlagSet("IAM addons", func(fs *pflag.FlagSet) {

pkg/ctl/scale/nodegroup.go

@@ -35,7 +35,13 @@ func scaleNodeGroupCmd(g *cmdutils.Grouping) *cobra.Command {
 		fs.StringVar(&cfg.Metadata.Name, "cluster", "", "EKS cluster name")
 		fs.StringVarP(&ng.Name, "name", "n", "", "Name of the nodegroup to scale")
 
-		fs.IntVarP(&ng.DesiredCapacity, "nodes", "N", -1, "total number of nodes (scale to this number)")
+		var desiredCapacity int
+		fs.IntVarP(&desiredCapacity, "nodes", "N", -1, "total number of nodes (scale to this number)")
+		cmd.PreRun = func(cmd *cobra.Command, args[] string) {
+			if f := cmd.Flag("nodes"); f.Changed {
+				ng.DesiredCapacity = &desiredCapacity
+			}
+		}
 
 		cmdutils.AddRegionFlag(fs, p)
 	})
@@ -70,7 +76,7 @@ func doScaleNodeGroup(p *api.ProviderConfig, cfg *api.ClusterConfig, ng *api.Nod
 		return fmt.Errorf("--name must be set")
 	}
 
-	if ng.DesiredCapacity < 0 {
+	if ng.DesiredCapacity == nil || *ng.DesiredCapacity < 0 {
 		return fmt.Errorf("number of nodes must be 0 or greater. Use the --nodes/-N flag")
 	}
 

pkg/ctl/utils/wait_nodes.go

@@ -36,7 +36,13 @@ func waitNodesCmd(g *cmdutils.Grouping) *cobra.Command {
 
 	group.InFlagSet("General", func(fs *pflag.FlagSet) {
 		fs.StringVar(&waitNodesKubeconfigPath, "kubeconfig", "kubeconfig", "path to read kubeconfig")
-		fs.IntVarP(&ng.MinSize, "nodes-min", "m", api.DefaultNodeCount, "minimum number of nodes to wait for")
+		var minSize int
+		fs.IntVarP(&minSize, "nodes-min", "m", api.DefaultNodeCount, "minimum number of nodes to wait for")
+		cmd.PreRun = func(cmd *cobra.Command, args[] string) {
+			if f := cmd.Flag("nodes-min"); f.Changed {
+				ng.MinSize = &minSize
+			}
+		}
 		fs.DurationVar(&p.WaitTimeout, "timeout", api.DefaultWaitTimeout, "how long to wait")
 	})
 

pkg/eks/nodegroup.go

@@ -81,7 +81,7 @@ func getNodes(clientSet *clientset.Clientset, ng *api.NodeGroup) (int, error) {
 
 // WaitForNodes waits till the nodes are ready
 func (c *ClusterProvider) WaitForNodes(clientSet *clientset.Clientset, ng *api.NodeGroup) error {
-	if ng.MinSize == 0 {
+	if *ng.MinSize == 0 {
 		return nil
 	}
 	timer := time.After(c.Provider.WaitTimeout())
@@ -97,7 +97,7 @@ func (c *ClusterProvider) WaitForNodes(clientSet *clientset.Clientset, ng *api.N
 	}
 
 	logger.Info("waiting for at least %d node(s) to become ready in %q", ng.MinSize, ng.Name)
-	for !timeout && counter <= ng.MinSize {
+	for !timeout && counter <= *ng.MinSize {
 		select {
 		case event := <-watcher.ResultChan():
 			logger.Debug("event = %#v", event)

pkg/utils/kubeconfig/kubeconfig_test.go

@@ -146,9 +146,9 @@ var _ = Describe("Kubeconfig", func() {
 					SSHPublicKeyPath:  "~/.ssh/id_rsa.pub",
 					SSHPublicKey:      []uint8(nil),
 					SSHPublicKeyName:  "",
-					DesiredCapacity:   2,
-					MinSize:           0,
-					MaxSize:           0,
+					DesiredCapacity:   nil,
+					MinSize:           nil,
+					MaxSize:           nil,
 					MaxPodsPerNode:    0,
 					IAM: &eksctlapi.NodeGroupIAM{
 						AttachPolicyARNs: []string(nil),