Add distribution validation with structured error handling

toolkit/tools/imagecreator/distribution.go

@@ -0,0 +1,54 @@
+// Copyright (c) Microsoft Corporation.
+// Licensed under the MIT License.
+
+package main
+
+import (
+	"fmt"
+	"strings"
+
+	"github.com/microsoft/azure-linux-image-tools/toolkit/tools/imagecustomizerapi"
+)
+
+// distribution represents a supported Linux distribution and version combination
+type distribution struct {
+	name    string
+	version string
+}
+
+// GetDistribution validates and returns a distribution from the CLI args
+func (c *ImageCreatorCmd) getDistribution() (*distribution, error) {
+	dist := &distribution{
+		name:    c.Distro,
+		version: c.DistroVersion,
+	}
+	if err := dist.validate(); err != nil {
+		return nil, err
+	}
+	return dist, nil
+}
+
+// Validate ensures the distribution and version combination is supported
+func (d *distribution) validate() error {
+	// Get supported versions for this distribution
+
+	supportedDistros := imagecustomizerapi.GetSupportedDistros()
+	validVersions, exists := supportedDistros[d.name]
+	if !exists {
+		distros := make([]string, 0, len(supportedDistros))
+		for d := range supportedDistros {
+			distros = append(distros, d)
+		}
+		return fmt.Errorf("unsupported distribution %q. Supported distributions are: %s",
+			d.name, strings.Join(distros, ", "))
+	}
+
+	// Validate version
+	for _, v := range validVersions {
+		if v == d.version {
+			return nil
+		}
+	}
+	return fmt.Errorf("unsupported version %q for distribution %q. Supported versions: %s",
+		d.version, d.name, strings.Join(validVersions, ", "))
+}

toolkit/tools/imagecreator/main.go

@@ -28,7 +28,7 @@ type ImageCreatorCmd struct {
 	OutputImageFile   string   `name:"output-image-file" help:"Path to write the customized image to."`
 	OutputImageFormat string   `name:"output-image-format" placeholder:"(vhd|vhd-fixed|vhdx|qcow2|raw)" help:"Format of output image." enum:"${imageformat}" default:""`
 	Distro            string   `name:"distro" help:"Target distribution for the image." enum:"azurelinux,fedora" default:"azurelinux"`
-	DistroVersion     string   `name:"distro-version" help:"Target distribution version (e.g., 3.0 for Azure Linux, 42 for Fedora)." default:""`
+	DistroVersion     string   `name:"distro-version" help:"Target distribution version (e.g., 3.0 for Azure Linux, 42 for Fedora)." default:"3.0"`
 	exekong.LogFlags
 	PackageSnapshotTime string `name:"package-snapshot-time" help:"Only packages published before this snapshot time will be available during customization. Supports 'YYYY-MM-DD' or full RFC3339 timestamp (e.g., 2024-05-20T23:59:59Z)."`
 }
@@ -54,8 +54,13 @@ func main() {
 
 	logger.InitBestEffort(ptrutils.PtrTo(cli.LogFlags.AsLoggerFlags()))
 
-	err := imagecreatorlib.CreateImageWithConfigFile(ctx, cli.BuildDir, cli.ConfigFile, cli.RpmSources,
-		cli.ToolsTar, cli.OutputImageFile, cli.OutputImageFormat, cli.Distro, cli.DistroVersion,
+	dist, err := cli.getDistribution()
+	if err != nil {
+		log.Fatalf("invalid distribution arguments: %v", err)
+	}
+
+	err = imagecreatorlib.CreateImageWithConfigFile(ctx, cli.BuildDir, cli.ConfigFile, cli.RpmSources,
+		cli.ToolsTar, cli.OutputImageFile, cli.OutputImageFormat, dist.name, dist.version,
 		cli.PackageSnapshotTime)
 	if err != nil {
 		log.Fatalf("image creation failed:\n%v", err)

toolkit/tools/imagecustomizerapi/distribution.go

@@ -0,0 +1,17 @@
+// Copyright (c) Microsoft Corporation.
+// Licensed under the MIT License.
+
+package imagecustomizerapi
+
+const (
+	DistroNameAzureLinux string = "azurelinux"
+	DistroNameFedora     string = "fedora"
+)
+
+func GetSupportedDistros() map[string][]string {
+	// supportedDistros defines valid distribution and version combinations
+	return map[string][]string{
+		DistroNameAzureLinux: {"2.0", "3.0"},
+		DistroNameFedora:     {"42"},
+	}
+}

toolkit/tools/pkg/imagecustomizerlib/distrohandler.go

@@ -12,25 +12,6 @@ import (
 	"github.com/microsoft/azure-linux-image-tools/toolkit/tools/internal/targetos"
 )
 
-// PackageManagerType represents the type of package manager
-type PackageManagerType string
-
-const (
-	packageManagerTDNF PackageManagerType = "tdnf"
-	packageManagerDNF  PackageManagerType = "dnf"
-)
-
-// PackageType represents the type of package format
-type PackageType string
-
-// DistroName represents the distribution name
-type DistroName string
-
-const (
-	distroNameAzureLinux DistroName = "azurelinux"
-	distroNameFedora     DistroName = "fedora"
-)
-
 // distroHandler represents the interface for distribution-specific configuration
 type distroHandler interface {
 	GetTargetOs() targetos.TargetOs
@@ -68,9 +49,9 @@ func NewDistroHandlerFromImageConnection(imageConnection *imageconnection.ImageC
 // NewDistroHandler creates the appropriate distro handler with version support (legacy)
 func NewDistroHandler(distroName string, version string) distroHandler {
 	switch distroName {
-	case string(distroNameFedora):
+	case string(imagecustomizerapi.DistroNameFedora):
 		return newFedoraDistroHandler(version)
-	case string(distroNameAzureLinux):
+	case string(imagecustomizerapi.DistroNameAzureLinux):
 		return newAzureLinuxDistroHandler(version)
 	default:
 		panic("unsupported distro name: " + distroName)