added validation for clustername and nodegroup name for cloudformatio…

…n error and updated docs

pkg/ctl/cmdutils/cmdutils.go

@@ -3,6 +3,7 @@ package cmdutils
 import (
 	"fmt"
 	"os"
+	"regexp"
 	"strings"
 	"time"
 
@@ -103,6 +104,12 @@ func GetNameArg(args []string) string {
 	return ""
 }
 
+// IsValidNameArg checks whether the name contains invalid characters
+func IsValidNameArg(name string) bool {
+	re := regexp.MustCompile(`[^a-zA-Z0-9\-]+`)
+	return !re.MatchString(name)
+}
+
 // AddCommonFlagsForAWS adds common flags for api.ProviderConfig
 func AddCommonFlagsForAWS(group *NamedFlagSetGroup, p *api.ProviderConfig, addCfnOptions bool) {
 	group.InFlagSet("AWS client", func(fs *pflag.FlagSet) {
@@ -219,6 +226,11 @@ func ErrFlagAndArg(kind, flag, arg string) error {
 	return fmt.Errorf("%s=%s and argument %s %s", kind, flag, arg, IncompatibleFlags)
 }
 
+// ErrInvalidName error when invalid characters for a name is provided
+func ErrInvalidName(name string) error {
+	return fmt.Errorf("validation for %s failed, name must satisfy regular expression pattern: [a-zA-Z][-a-zA-Z0-9]*", name)
+}
+
 // ErrMustBeSet is a common error message
 func ErrMustBeSet(pathOrFlag string) error {
 	return fmt.Errorf("%s must be set", pathOrFlag)

pkg/ctl/create/cluster.go

@@ -107,6 +107,10 @@ func doCreateCluster(cmd *cmdutils.Cmd, ngFilter *filter.NodeGroupFilter, params
 	cfg := cmd.ClusterConfig
 	meta := cmd.ClusterConfig.Metadata
 
+	if meta.Name != "" && !cmdutils.IsValidNameArg(meta.Name) {
+		return cmdutils.ErrInvalidName(meta.Name)
+	}
+
 	printer := printers.NewJSONPrinter()
 
 	ctl, err := cmd.NewCtl()

pkg/ctl/create/cluster_test.go

@@ -45,6 +45,8 @@ var _ = Describe("create cluster", func() {
 			Entry("without cluster name", ""),
 			Entry("with cluster name as flag", "--name", "clusterName"),
 			Entry("with cluster name as argument", "clusterName"),
+			Entry("with cluster name with hyphen as flag", "--name", "my-cluster-name-is-fine10"),
+			Entry("with cluster name with hyphen as argument", "my-Cluster-name-is-fine10"),
 			// vpc networking flags
 			Entry("with vpc-cidr flag", "--vpc-cidr", "10.0.0.0/20"),
 			Entry("with vpc-private-subnets flag", "--vpc-private-subnets", "10.0.0.0/24"),
@@ -97,6 +99,14 @@ var _ = Describe("create cluster", func() {
 				args:  []string{"cluster", "--invalid", "dummy"},
 				error: "unknown flag: --invalid",
 			}),
+			Entry("with --name option with invalid characters that are rejected by cloudformation", invalidParamsCase{
+				args:  []string{"test-k8_cluster01"},
+				error: fmt.Errorf("Error: validation for test-k8_cluster01 failed, name must satisfy regular expression pattern: [a-zA-Z][-a-zA-Z0-9]*"),
+			}),
+			Entry("with cluster name argument with invalid characters that are rejected by cloudformation", invalidParamsCase{
+				args:  []string{"--name", "eksctl-testing-k_8_cluster01"},
+				error: fmt.Errorf("Error: validation for eksctl-testing-k_8_cluster01 failed, name must satisfy regular expression pattern: [a-zA-Z][-a-zA-Z0-9]*"),
+			}),
 		)
 	})
 
@@ -120,6 +130,8 @@ var _ = Describe("create cluster", func() {
 			Entry("without cluster name", ""),
 			Entry("with cluster name as flag", "--name", "clusterName"),
 			Entry("with cluster name as argument", "clusterName"),
+			Entry("with cluster name with hyphen as flag", "--name", "my-cluster-name-is-fine10"),
+			Entry("with cluster name with hyphen as argument", "my-Cluster-name-is-fine10"),
 			// vpc networking flags
 			Entry("with vpc-cidr flag", "--vpc-cidr", "10.0.0.0/20"),
 			Entry("with vpc-private-subnets flag", "--vpc-private-subnets", "10.0.0.0/24"),
@@ -167,6 +179,14 @@ var _ = Describe("create cluster", func() {
 				args:  []string{"cluster", "--invalid", "dummy"},
 				error: "unknown flag: --invalid",
 			}),
+			Entry("with --name option with invalid characters that are rejected by cloudformation", invalidParamsCase{
+				args:  []string{"test-k8_cluster01"},
+				error: fmt.Errorf("Error: validation for test-k8_cluster01 failed, name must satisfy regular expression pattern: [a-zA-Z][-a-zA-Z0-9]*"),
+			}),
+			Entry("with cluster name argument with invalid characters that are rejected by cloudformation", invalidParamsCase{
+				args:  []string{"--name", "eksctl-testing-k_8_cluster01"},
+				error: fmt.Errorf("Error: validation for eksctl-testing-k_8_cluster01 failed, name must satisfy regular expression pattern: [a-zA-Z][-a-zA-Z0-9]*"),
+			}),
 		)
 	})
 })

pkg/ctl/create/nodegroup.go

@@ -26,6 +26,10 @@ type nodegroupOptions struct {
 
 func createNodeGroupCmd(cmd *cmdutils.Cmd) {
 	createNodeGroupCmdWithRunFunc(cmd, func(cmd *cmdutils.Cmd, ng *api.NodeGroup, options nodegroupOptions) error {
+		if ng.Name != "" && !cmdutils.IsValidNameArg(ng.Name) {
+			return cmdutils.ErrInvalidName(ng.Name)
+		}
+
 		ngFilter := filter.NewNodeGroupFilter()
 		if err := cmdutils.NewCreateNodeGroupLoader(cmd, ng, ngFilter, options.CreateNGOptions, options.CreateManagedNGOptions).Load(); err != nil {
 			return errors.Wrap(err, "couldn't create node group filter from command line options")

pkg/ctl/create/nodegroup_test.go

@@ -29,7 +29,9 @@ var _ = Describe("create nodegroup", func() {
 				Expect(count).To(Equal(1))
 			},
 			Entry("with nodegroup name as flag", "--name", "nodegroupName"),
+			Entry("with nodegroup name with a hyphen as flag", "--name", "nodegroup-name"),
 			Entry("with nodegroup name as argument", "nodegroupName"),
+			Entry("with nodegroup name with a hyphen as argument", "nodegroup-name"),
 			Entry("with node-type flag", "--node-type", "m5.large"),
 			Entry("with nodes flag", "--nodes", "2"),
 			Entry("with nodes-min flag", "--nodes-min", "2"),
@@ -81,6 +83,10 @@ var _ = Describe("create nodegroup", func() {
 				args:  []string{"--cluster", "foo", "--instance-types", "some-type"},
 				error: "--instance-types is only valid with managed nodegroups (--managed)",
 			}),
+			Entry("with nodegroup name as flag with invalid characters", invalidParamsCase{
+				args:  []string{"--cluster", "clusterName", "--name", "eksctl-ng_k8s_nodegroup1"},
+				error: fmt.Errorf("Error: validation for eksctl-ng_k8s_nodegroup1 failed, name must satisfy regular expression pattern: [a-zA-Z][-a-zA-Z0-9]*"),
+			}),
 		)
 	})
 
@@ -104,7 +110,9 @@ var _ = Describe("create nodegroup", func() {
 			},
 			Entry("without nodegroup name", ""),
 			Entry("with nodegroup name as flag", "--name", "nodegroupName"),
+			Entry("with nodegroup name with a hyphen as flag", "--name", "nodegroup-name"),
 			Entry("with nodegroup name as argument", "nodegroupName"),
+			Entry("with nodegroup name with a hyphen as argument", "nodegroup-name"),
 			Entry("with node-type flag", "--node-type", "m5.large"),
 			Entry("with nodes flag", "--nodes", "2"),
 			Entry("with nodes-min flag", "--nodes-min", "2"),
@@ -140,6 +148,10 @@ var _ = Describe("create nodegroup", func() {
 				args:  []string{"--invalid", "dummy"},
 				error: "unknown flag: --invalid",
 			}),
+			Entry("with nodegroup name as flag with invalid characters", invalidParamsCase{
+				args:  []string{"--name", "eksctl-ng_k8s_nodegroup1"},
+				error: fmt.Errorf("Error: validation for eksctl-ng_k8s_nodegroup1 failed, name must satisfy regular expression pattern: [a-zA-Z][-a-zA-Z0-9]*"),
+			}),
 		)
 	})
 })

userdocs/src/usage/creating-and-managing-clusters.md

@@ -97,6 +97,9 @@ nodeGroups:
         imageBuilder: true
 ```
 
+!!! note
+    The cluster name or nodegroup name can contain only alphanumeric characters (case-sensitive) and hyphens. It must start with an alphabetic character and can't be longer than 128 characters otherwise you will get a validation error. More information can be found [here](https://docs.aws.amazon.com/AWSCloudFormation/latest/UserGuide/cfn-using-console-create-stack-parameters.html)
+
 To delete this cluster, run:
 
 ```