feat(openapi): generated classes implement interfaces

Signed-off-by: Marc Nuri <marc@marcnuri.com>

kubernetes-model-generator/openapi/generator/pkg/openapi/openapi-gen-processors.go

@@ -77,26 +77,22 @@ func addOrAppend(commentLines []string, prefix, value string) []string {
 	}
 	return commentLines
 }
+func publicInterfaceName(name string) string {
+	if unicode.IsUpper(rune(name[0])) {
+		return name
+	}
+	return string(unicode.ToUpper(rune(name[0]))) + name[1:]
+}
 
 // func processProtobufOneof
 // To generate interfaces and extending classes for oneof fields
 // This is something extensively used in the Istio API, that uses these as marker interfaces
 //
 // For processing we'll add +k8s:openapi-gen=x-kubernetes tags that will be later processed by kube-openapi and added to the OpenAPI json spec
 func processProtobufOneof(_ *generator.Context, pkg *types.Package, t *types.Type, m *types.Member, memberIndex int) {
-	publicInterfaceName := func(name string) string {
-		if unicode.IsUpper(rune(name[0])) {
-			return name
-		}
-		return string(unicode.ToUpper(rune(name[0]))) + name[1:]
-	}
 	// Interfaces
 	protobufOneOf := reflect.StructTag(m.Tags).Get("protobuf_oneof")
 	if protobufOneOf != "" {
-		// kube-openapi doesn't handle interfaces, so we need to change the interface to a struct
-		m.Type.Kind = types.Struct
-		// Ensure it's exported
-		t.Members[memberIndex].Type.Name.Name = publicInterfaceName(m.Type.Name.Name)
 		//// Add comment tag to the referenced type and mark it as an interface
 		t.Members[memberIndex].Type.CommentLines = append(m.Type.CommentLines, "+k8s:openapi-gen=x-kubernetes-fabric8-type:interface")
 		// Add comment tag to the current type to mark it as it has fields that are interfaces (useful for the OpenAPI Java generator)
@@ -119,13 +115,36 @@ func processProtobufOneof(_ *generator.Context, pkg *types.Package, t *types.Typ
 	}
 }
 
+// processProtobufPackageOneOf function to process the protobuf package and change the interfaces to structs
+// kube-openapi doesn't handle interfaces, so we need to change the interface to a struct
+func processProtobufPackageOneOf(_ *generator.Context, pkg *types.Package) {
+	for _, t := range pkg.Types {
+		if t.Kind != types.Interface {
+			continue
+		}
+		openApiGen := gengo.ExtractCommentTags("+", t.CommentLines)["k8s:openapi-gen"]
+		if len(openApiGen) > 0 {
+			for _, openApiGenValue := range openApiGen {
+				if openApiGenValue == "x-kubernetes-fabric8-type:interface" {
+					// Change to Struct so that it's processed by kube-openapi
+					t.Kind = types.Struct
+					// Ensure it's public so that it can be exported
+					t.Name.Name = publicInterfaceName(t.Name.Name)
+					break
+				}
+			}
+		}
+	}
+}
+
 // processProtobufTags function to process the protobuf field tags and fix json tags that might have mismatched names for serialization
 // This happens for most of the istio APIs
 func processProtobufTags(_ *generator.Context, _ *types.Package, t *types.Type, m *types.Member, memberIndex int) {
 	tags := reflect.StructTag(m.Tags)
 	protobufTag := tags.Get("protobuf")
 	jsonTag := tags.Get("json")
 	if protobufTag != "" && strings.Contains(protobufTag, "json=") {
+		// TODO, consider also name= (sometimes this is included instad of json=)
 		name := strings.Split(protobufTag, "json=")[1]
 		name = strings.Split(name, ",")[0]
 		var updatedJsonTag string

kubernetes-model-generator/openapi/generator/pkg/openapi/openapi-gen.go

@@ -32,19 +32,25 @@ type GoGenerator struct {
 	openapiargs.Args
 	Patterns   []string
 	inputPkgs  map[string]bool
-	processors []func(context *generator.Context, pkg *types.Package, t *types.Type, member *types.Member, memberIndex int)
+	// memberProcessors are functions that are applied to each member of a type
+	memberProcessors []func(context *generator.Context, pkg *types.Package, t *types.Type, member *types.Member, memberIndex int)
+	// packageProcessors are functions that are applied to each package once all type members have been processed for that package
+	packageProcessors []func(context *generator.Context, pkg *types.Package)
 }
 
 func (g *GoGenerator) Generate() error {
 	g.ReportFilename = g.OutputFile + ".report.txt"
-	g.processors = []func(context *generator.Context, pkg *types.Package, t *types.Type, member *types.Member, memberIndex int){
+	g.memberProcessors = []func(context *generator.Context, pkg *types.Package, t *types.Type, member *types.Member, memberIndex int){
 		processMapKeyTypes,
 		processOmitPrivateFields,
 		processPatchComments,
 		processProtobufOneof,
 		processProtobufTags,
 		processSwaggerIgnore,
 	}
+	g.packageProcessors = []func(context *generator.Context, pkg *types.Package){
+		processProtobufPackageOneOf,
+	}
 	return gengo.Execute(
 		generators.NameSystems(),
 		generators.DefaultNameSystem(),
@@ -89,11 +95,14 @@ func (g *GoGenerator) processUniverse(context *generator.Context) {
 	for _, pkg := range context.Universe {
 		for _, t := range pkg.Types {
 			for memberIndex, member := range t.Members {
-				for _, processor := range g.processors {
-					processor(context, pkg, t, &member, memberIndex)
+				for _, memeberProcessor := range g.memberProcessors {
+					memeberProcessor(context, pkg, t, &member, memberIndex)
 				}
 			}
 		}
+		for _, packageProcessor := range g.packageProcessors {
+			packageProcessor(context, pkg)
+		}
 	}
 
 	// Non-deterministic bug-fix

kubernetes-model-generator/openapi/maven-plugin/pom.xml

@@ -67,16 +67,6 @@
       <artifactId>swagger-parser</artifactId>
       <version>2.1.23</version>
     </dependency>
-    <dependency>
-      <groupId>org.junit.jupiter</groupId>
-      <artifactId>junit-jupiter-engine</artifactId>
-      <scope>test</scope>
-    </dependency>
-    <dependency>
-      <groupId>org.junit.jupiter</groupId>
-      <artifactId>junit-jupiter-params</artifactId>
-      <scope>test</scope>
-    </dependency>
   </dependencies>
   <build>
     <plugins>