Add dev flag for unsupported image builds (#5168)

Add --dev flag to image-builder CLI, it will be used
to enable builds that are not officially supported
such as ubuntu 20.04

Author: 2ez4szliu

projects/aws/image-builder/ATTRIBUTION.txt

@@ -443,7 +443,7 @@ OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 
 ------
 
-** golang.org/go; version go1.24.6 --
+** golang.org/go; version go1.24.12 --
 https://github.com/golang/go
 
 ** golang.org/x/net; version v0.38.0 --

projects/aws/image-builder/builder/types.go

@@ -21,7 +21,6 @@ var SupportedHypervisors = []string{
 }
 
 var SupportedUbuntuVersions = []string{
-	"20.04",
 	"22.04",
 	"24.04",
 }
@@ -59,6 +58,7 @@ type BuildOptions struct {
 	AnsibleVerbosity   int
 	EKSAReleaseVersion string
 	BuilderType        string
+	Dev                bool
 }
 
 type VsphereConfig struct {

projects/aws/image-builder/cmd/build.go

@@ -43,7 +43,7 @@ var buildCmd = &cobra.Command{
 func init() {
 	rootCmd.AddCommand(buildCmd)
 	buildCmd.Flags().StringVar(&bo.Os, "os", "", "Operating system to use for EKS-A node image")
-	buildCmd.Flags().StringVar(&bo.OsVersion, "os-version", "", "Operating system version to use for EKS-A node image. Can be 20.04, 22.04 or 24.04 for Ubuntu, 8 or 9 for Redhat.")
+	buildCmd.Flags().StringVar(&bo.OsVersion, "os-version", "", "Operating system version to use for EKS-A node image. Can be 22.04 or 24.04 for Ubuntu, 8 or 9 for Redhat.")
 	buildCmd.Flags().StringVar(&bo.Hypervisor, "hypervisor", "", "Target hypervisor for EKS-A node image")
 	buildCmd.Flags().StringVar(&baremetalConfigFile, "baremetal-config", "", "Path to Baremetal Config file")
 	buildCmd.Flags().StringVar(&vSphereConfigFile, "vsphere-config", "", "Path to vSphere Config file")
@@ -58,6 +58,7 @@ func init() {
 	buildCmd.Flags().StringVar(&bo.ManifestTarball, "manifest-tarball", "", "Path to Image Builder built EKS-D/A manifest tarball")
 	buildCmd.Flags().IntVar(&bo.AnsibleVerbosity, "ansible-verbosity", 0, "Verbosity level for the Ansible tasks run during image building, should be in the range 0-6")
 	buildCmd.Flags().BoolVar(&bo.AirGapped, "air-gapped", false, "Flag to instruct image builder to run in air-gapped mode. Requires --manifest-tarball to be set")
+	buildCmd.Flags().BoolVar(&bo.Dev, "dev", false, "Development mode flag. When set to true, unsupported builds such as Ubuntu 20.04 will be enabled")
 	buildCmd.Flags().StringVar(&builderType, "builder", builder.BuilderTypeIso, "Builder type for VSphere. Can be iso or clone")
 	if err := buildCmd.MarkFlagRequired("os"); err != nil {
 		log.Fatalf("Error marking flag as required: %v", err)
@@ -89,7 +90,7 @@ func ValidateInputs(bo *builder.BuildOptions) error {
 
 	if bo.Os == builder.Ubuntu && bo.OsVersion == "" {
 		// maintain previous default
-		bo.OsVersion = "20.04"
+		bo.OsVersion = "22.04"
 	}
 
 	if bo.Os == builder.RedHat && bo.OsVersion == "" {
@@ -105,7 +106,7 @@ func ValidateInputs(bo *builder.BuildOptions) error {
 		log.Fatalf("Clone builder is only supported for vSphere hypervisor")
 	}
 
-	if err = validateOSVersion(bo.Os, bo.OsVersion); err != nil {
+	if err = validateOSVersion(bo.Os, bo.OsVersion, bo.Dev); err != nil {
 		log.Fatal(err.Error())
 	}
 
@@ -160,7 +161,7 @@ func ValidateInputs(bo *builder.BuildOptions) error {
 	bo.Hypervisor = strings.ToLower(bo.Hypervisor)
 
 	if bo.OsVersion != "" {
-		// From this point forward use 2004 instead of 20.04 for Ubuntu versions to upstream image-builder
+		// From this point forward use 2204 instead of 22.04 for Ubuntu versions to upstream image-builder
 		bo.OsVersion = strings.ReplaceAll(bo.OsVersion, ".", "")
 	}
 
@@ -400,13 +401,22 @@ func validateSupportedHypervisors(hypervisor string) error {
 	return fmt.Errorf("%s is not supported yet. Please select one of %s", hypervisor, strings.Join(builder.SupportedHypervisors, ","))
 }
 
-func validateOSVersion(os, osVersion string) error {
+func validateOSVersion(os, osVersion string, dev bool) error {
 	if os != builder.RedHat && os != builder.Ubuntu {
 		return fmt.Errorf("%s is not a supported OS", os)
 	}
 
-	if os == builder.Ubuntu && !builder.SliceContains(builder.SupportedUbuntuVersions, osVersion) {
-		return fmt.Errorf("%s is not a supported version of Ubuntu. Please select one of %s", osVersion, strings.Join(builder.SupportedUbuntuVersions, ","))
+	if os == builder.Ubuntu {
+		// Ubuntu 20.04 only allowed when dev=true
+		if osVersion == "20.04" {
+			if !dev {
+				return fmt.Errorf("%s is not a supported version of Ubuntu. Please select one of %s", osVersion, strings.Join(builder.SupportedUbuntuVersions, ","))
+			}
+		} else {
+			if !builder.SliceContains(builder.SupportedUbuntuVersions, osVersion) {
+				return fmt.Errorf("%s is not a supported version of Ubuntu. Please select one of %s", osVersion, strings.Join(builder.SupportedUbuntuVersions, ","))
+			}
+		}
 	}
 
 	if os == builder.RedHat && !builder.SliceContains(builder.SupportedRedHatVersions, osVersion) {

projects/aws/image-builder/cmd/build_test.go

@@ -104,11 +104,20 @@ func TestValidateOSVersionCombinations(t *testing.T) {
 		wantErr      string
 	}{
 		{
-			testName: "Ubuntu 20.04",
+			testName: "Ubuntu 20.04 without dev flag",
 			buildOptions: builder.BuildOptions{
 				Os:        "ubuntu",
 				OsVersion: "20.04",
 			},
+			wantErr: "20.04 is not a supported version of Ubuntu. Please select one of 22.04,24.04",
+		},
+		{
+			testName: "Ubuntu 20.04 with dev flag",
+			buildOptions: builder.BuildOptions{
+				Os:        "ubuntu",
+				OsVersion: "20.04",
+				Dev:       true,
+			},
 			wantErr: "",
 		},
 		{
@@ -133,7 +142,7 @@ func TestValidateOSVersionCombinations(t *testing.T) {
 				Os:        "ubuntu",
 				OsVersion: "26.04",
 			},
-			wantErr: "26.04 is not a supported version of Ubuntu. Please select one of 20.04,22.04,24.04",
+			wantErr: "26.04 is not a supported version of Ubuntu. Please select one of 22.04,24.04",
 		},
 		{
 			testName: "Redhat 8",
@@ -163,7 +172,7 @@ func TestValidateOSVersionCombinations(t *testing.T) {
 
 	for _, tt := range testCases {
 		t.Run(tt.testName, func(t *testing.T) {
-			err := validateOSVersion(tt.buildOptions.Os, tt.buildOptions.OsVersion)
+			err := validateOSVersion(tt.buildOptions.Os, tt.buildOptions.OsVersion, tt.buildOptions.Dev)
 			if tt.wantErr == "" {
 				assert.NoError(t, err)
 			} else {
@@ -324,6 +333,7 @@ func TestValidateInputsFirmwareDefaulting(t *testing.T) {
 				OsVersion:  "20.04",
 				Hypervisor: "baremetal",
 				Firmware:   "",
+				Dev:        true,
 			},
 			wantFirmware: "efi",
 		},

projects/kubernetes-sigs/image-builder/build/build_image.sh

@@ -118,18 +118,18 @@ if [[ $image_format == "ova" ]]; then
   cat $image_builder_config_file
 
   # Run image-builder CLI
-  retry_image_builder build --hypervisor vsphere --os $image_os $image_os_version_arg --vsphere-config $image_builder_config_file --release-channel $release_channel $firmware_arg
+  retry_image_builder build --hypervisor vsphere --os $image_os $image_os_version_arg --vsphere-config $image_builder_config_file --release-channel $release_channel $firmware_arg --dev true
 elif [[ $image_format == "raw" ]]; then
   echo "Creating Bare metal image-builder config"
   if [[ $image_os == "ubuntu" ]]; then
     # Run image-builder CLI
-    retry_image_builder build --hypervisor baremetal --os $image_os $image_os_version_arg --release-channel $release_channel
+    retry_image_builder build --hypervisor baremetal --os $image_os $image_os_version_arg --release-channel $release_channel --dev true
   elif [[ $image_os == "redhat" ]]; then
     image_builder_config_file=$redhat_config_file
     cat $image_builder_config_file
 
     # Run image-builder CLI
-    retry_image_builder build --hypervisor baremetal --os $image_os $image_os_version_arg --release-channel $release_channel --baremetal-config $image_builder_config_file
+    retry_image_builder build --hypervisor baremetal --os $image_os $image_os_version_arg --release-channel $release_channel --baremetal-config $image_builder_config_file --dev true
   fi
 elif [[ $image_format == "cloudstack" ]]; then
   if [[ $image_os != "redhat" ]]; then
@@ -142,7 +142,7 @@ elif [[ $image_format == "cloudstack" ]]; then
   cat $image_builder_config_file
 
   # Run image-builder CLI
-  retry_image_builder build --hypervisor cloudstack --os $image_os $image_os_version_arg --release-channel $release_channel --cloudstack-config $image_builder_config_file
+  retry_image_builder build --hypervisor cloudstack --os $image_os $image_os_version_arg --release-channel $release_channel --cloudstack-config $image_builder_config_file --dev true
 elif [[ $image_format == "ami" ]]; then
   if [[ $image_os != "ubuntu" ]]; then
     echo "AMI builds do not support any non-ubuntu os"
@@ -157,7 +157,7 @@ elif [[ $image_format == "ami" ]]; then
   cat $image_builder_config_file
 
   # Run image-builder CLI
-  retry_image_builder build --hypervisor ami --os $image_os $image_os_version_arg --release-channel $release_channel --ami-config $image_builder_config_file
+  retry_image_builder build --hypervisor ami --os $image_os $image_os_version_arg --release-channel $release_channel --ami-config $image_builder_config_file --dev true
 elif [[ $image_format == "nutanix" ]]; then
   # Setup nutanix config
   nutanix_config_file="${HOME}/nutanix_config_file"
@@ -197,5 +197,5 @@ elif [[ $image_format == "nutanix" ]]; then
   cat $image_builder_config_file
 
   # Run image-builder CLI
-  retry_image_builder build --hypervisor nutanix --os $image_os $image_os_version_arg --nutanix-config $image_builder_config_file --release-channel $release_channel
+  retry_image_builder build --hypervisor nutanix --os $image_os $image_os_version_arg --nutanix-config $image_builder_config_file --release-channel $release_channel --dev true
 fi