Merge pull request #1078 from mtardy/pr/mtardy/type-alias-validation

🐛 pkg/crd: support validation on type alias to basic types

pkg/crd/schema.go

@@ -242,11 +242,30 @@ func localNamedToSchema(ctx *schemaContext, ident *ast.Ident) *apiext.JSONSchema
 		ctx.pkg.AddError(loader.ErrFromNode(fmt.Errorf("unknown type %s", ident.Name), ident))
 		return &apiext.JSONSchemaProps{}
 	}
+	// This reproduces the behavior we had pre gotypesalias=1 (needed if this
+	// project is compiled with default settings and Go >= 1.23).
+	if aliasInfo, isAlias := typeInfo.(*types.Alias); isAlias {
+		typeInfo = aliasInfo.Underlying()
+	}
 	if basicInfo, isBasic := typeInfo.(*types.Basic); isBasic {
 		typ, fmt, err := builtinToType(basicInfo, ctx.allowDangerousTypes)
 		if err != nil {
 			ctx.pkg.AddError(loader.ErrFromNode(err, ident))
 		}
+		// Check for type aliasing to a basic type for gotypesalias=0. See more
+		// in documentation https://pkg.go.dev/go/types#Alias:
+		// > For gotypesalias=1, alias declarations produce an Alias type.
+		// > Otherwise, the alias information is only in the type name, which
+		// > points directly to the actual (aliased) type.
+		if basicInfo.Name() != ident.Name {
+			ctx.requestSchema("", ident.Name)
+			link := TypeRefLink("", ident.Name)
+			return &apiext.JSONSchemaProps{
+				Type:   typ,
+				Format: fmt,
+				Ref:    &link,
+			}
+		}
 		return &apiext.JSONSchemaProps{
 			Type:   typ,
 			Format: fmt,

pkg/crd/testdata/cronjob_types.go

@@ -335,6 +335,14 @@ type CronJobSpec struct {
 	// This tests that string alias is handled correctly.
 	StringAlias StringAlias `json:"stringAlias,omitempty"`
 
+	// This tests that validation on a string alias type is handled correctly.
+	// +kubebuilder:validation:MinLength=1
+	// +kubebuilder:validation:MaxLength=255
+	StringAliasAddedValidation StringAlias `json:"stringAliasAddedValidation,omitempty"`
+
+	// This tests that validation on a the string alias type itself is handled correctly.
+	StringAliasAlreadyValidated StringAliasWithValidation `json:"stringAliasAlreadyValidated,omitempty"`
+
 	// This tests string slice validation.
 	// +kubebuilder:validation:MinItems=2
 	// +kubebuilder:validation:MaxItems=2
@@ -364,6 +372,10 @@ type CronJobSpec struct {
 
 type StringAlias = string
 
+// +kubebuilder:validation:MinLength=1
+// +kubebuilder:validation:MaxLength=255
+type StringAliasWithValidation = string
+
 type ContainsNestedMap struct {
 	InnerMap map[string]string `json:"innerMap,omitempty"`
 }

pkg/crd/testdata/testdata.kubebuilder.io_cronjobs.yaml

@@ -8984,6 +8984,16 @@ spec:
               stringAlias:
                 description: This tests that string alias is handled correctly.
                 type: string
+              stringAliasAddedValidation:
+                description: This tests that validation on a string alias type is handled correctly.
+                maxLength: 255
+                minLength: 1
+                type: string
+              stringAliasAlreadyValidated:
+                description: This tests that validation on a the string alias type itself is handled correctly.
+                maxLength: 255
+                minLength: 1
+                type: string
               stringPair:
                 description: This tests string slice validation.
                 items: