deepcopy-gen: re-add legacy scheme registration

examples/deepcopy-gen/generators/deepcopy.go

@@ -370,7 +370,56 @@ func argsFromType(ts ...*types.Type) generator.Args {
 
 func (g *genDeepCopy) Init(c *generator.Context, w io.Writer) error {
 	glog.V(5).Infof("Registering types in pkg %q", g.targetPackage)
-	return nil
+
+	// the legacy restration will go away when the cloner is removed from Kubernetes, replaced
+	// with static function calls to the DeepCopy methods.
+	return g.legacyRegistration(c, w)
+}
+
+func (g *genDeepCopy) legacyRegistration(c *generator.Context, w io.Writer) error {
+	conversionPackagePath := "k8s.io/apimachinery/pkg/conversion"
+	runtimePackagePath := "k8s.io/apimachinery/pkg/runtime"
+
+	cloner := c.Universe.Type(types.Name{Package: conversionPackagePath, Name: "Cloner"})
+	g.imports.AddType(cloner)
+	if !g.registerTypes {
+		sw := generator.NewSnippetWriter(w, c, "$", "$")
+		sw.Do("// Deprecated: GetGeneratedDeepCopyFuncs returns the generated funcs, since we aren't registering them.\n", nil)
+		sw.Do("func GetGeneratedDeepCopyFuncs() []conversion.GeneratedDeepCopyFunc{\n", nil)
+		sw.Do("return []conversion.GeneratedDeepCopyFunc{\n", nil)
+		for _, t := range g.typesForInit {
+			args := argsFromType(t).
+				With("typeof", c.Universe.Package("reflect").Function("TypeOf"))
+			sw.Do("{Fn: func(in interface{}, out interface{}, c *conversion.Cloner) error {in.(*$.type|raw$).DeepCopyInto(out.(*$.type|raw$)); return nil}, InType: $.typeof|raw$(&$.type|raw${})},\n", args)
+		}
+		sw.Do("}\n", nil)
+		sw.Do("}\n\n", nil)
+		return sw.Error()
+	}
+
+	sw := generator.NewSnippetWriter(w, c, "$", "$")
+	sw.Do("// Deprecated: register deep-copy functions.\n", nil)
+	sw.Do("func init() {\n", nil)
+	sw.Do("SchemeBuilder.Register(RegisterDeepCopies)\n", nil)
+	sw.Do("}\n\n", nil)
+
+	scheme := c.Universe.Type(types.Name{Package: runtimePackagePath, Name: "Scheme"})
+	schemePtr := &types.Type{
+		Kind: types.Pointer,
+		Elem: scheme,
+	}
+	sw.Do("// Deprecated: RegisterDeepCopies adds deep-copy functions to the given scheme. Public\n", nil)
+	sw.Do("// to allow building arbitrary schemes.\n", nil)
+	sw.Do("func RegisterDeepCopies(scheme $.|raw$) error {\n", schemePtr)
+	sw.Do("return scheme.AddGeneratedDeepCopyFuncs(\n", nil)
+	for _, t := range g.typesForInit {
+		args := argsFromType(t).
+			With("typeof", c.Universe.Package("reflect").Function("TypeOf"))
+		sw.Do("conversion.GeneratedDeepCopyFunc{Fn: func(in interface{}, out interface{}, c *conversion.Cloner) error {in.(*$.type|raw$).DeepCopyInto(out.(*$.type|raw$)); return nil}, InType: $.typeof|raw$(&$.type|raw${})},\n", args)
+	}
+	sw.Do(")\n", nil)
+	sw.Do("}\n\n", nil)
+	return sw.Error()
 }
 
 func (g *genDeepCopy) needsGeneration(t *types.Type) bool {