Allow separate additional repository validations

Signed-off-by: Atanas Dinov <[email protected]>

pkg/image/validation/os.go

@@ -182,16 +182,6 @@ func validateSuma(os *image.OperatingSystem) []FailedValidation {
 func validatePackages(os *image.OperatingSystem) []FailedValidation {
 	var failures []FailedValidation
 
-	if len(os.Packages.PKGList) == 0 {
-		if len(os.Packages.AdditionalRepos) > 0 {
-			failures = append(failures, FailedValidation{
-				UserMessage: "The 'packageList' field is required if any entries are specified under 'additionalRepos'.",
-			})
-		}
-
-		return failures
-	}
-
 	if slices.Contains(os.Packages.PKGList, "") {
 		failures = append(failures, FailedValidation{
 			UserMessage: "The 'packageList' field cannot contain empty values.",
@@ -206,6 +196,8 @@ func validatePackages(os *image.OperatingSystem) []FailedValidation {
 		})
 	}
 
+	// It is possible to only provide `additionalRepos` without listing any packages
+	// under `packageList` in the cases where RPMs are side-loaded under the `/rpms` directory.
 	var repoURLs []string
 
 	for _, repo := range os.Packages.AdditionalRepos {

pkg/image/validation/os_test.go

@@ -486,18 +486,6 @@ func TestPackages(t *testing.T) {
 				"The 'packageList' field cannot contain empty values.",
 			},
 		},
-		`missing packages`: {
-			Packages: image.Packages{
-				AdditionalRepos: []image.AddRepo{
-					{
-						URL: "foo",
-					},
-				},
-			},
-			ExpectedFailedMessages: []string{
-				"The 'packageList' field is required if any entries are specified under 'additionalRepos'.",
-			},
-		},
 		`duplicate packages`: {
 			Packages: image.Packages{
 				PKGList: []string{"foo", "bar", "foo", "bar", "baz"},