Implement experimental marshaler for OpenAPI V3

pkg/internal/flags.go

@@ -22,3 +22,4 @@ var UseOptimizedJSONUnmarshalingV3 bool = true
 
 // Used by tests to selectively disable experimental JSON marshaler
 var UseOptimizedJSONMarshaling bool = true
+var UseOptimizedJSONMarshalingV3 bool = true

pkg/spec3/benchmark_serialization_test.go

@@ -11,6 +11,7 @@ import (
 	"github.com/google/go-cmp/cmp"
 	fuzz "github.com/google/gofuzz"
 	"k8s.io/kube-openapi/pkg/internal"
+	jsontesting "k8s.io/kube-openapi/pkg/util/jsontesting"
 	"k8s.io/kube-openapi/pkg/validation/spec"
 )
 
@@ -71,6 +72,95 @@ func TestOpenAPIV3Deserialize(t *testing.T) {
 	}
 }
 
+func TestOpenAPIV3Serialize(t *testing.T) {
+	swagFile, err := os.Open("./testdata/appsv1spec.json")
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer swagFile.Close()
+	originalJSON, err := io.ReadAll(swagFile)
+	if err != nil {
+		t.Fatal(err)
+	}
+	var openapi *OpenAPI
+	if err := json.Unmarshal(originalJSON, &openapi); err != nil {
+		t.Fatal(err)
+	}
+
+	internal.UseOptimizedJSONUnmarshalingV3 = false
+	want, err := json.Marshal(openapi)
+	if err != nil {
+		t.Fatal(err)
+	}
+	internal.UseOptimizedJSONUnmarshalingV3 = true
+	got, err := openapi.MarshalJSON()
+	if err != nil {
+		t.Fatal(err)
+	}
+	if err := jsontesting.JsonCompare(want, got); err != nil {
+		t.Errorf("marshal doesn't match: %v", err)
+	}
+}
+
+func TestOpenAPIV3SerializeFuzzed(t *testing.T) {
+	var fuzzer *fuzz.Fuzzer
+	fuzzer = fuzz.NewWithSeed(1646791953)
+	fuzzer.MaxDepth(13).NilChance(0.075).NumElements(1, 2)
+	fuzzer.Funcs(OpenAPIV3FuzzFuncs...)
+
+	for i := 0; i < 100; i++ {
+		openapi := &OpenAPI{}
+		fuzzer.Fuzz(openapi)
+
+		internal.UseOptimizedJSONUnmarshalingV3 = false
+		want, err := json.Marshal(openapi)
+		if err != nil {
+			t.Fatal(err)
+		}
+		internal.UseOptimizedJSONUnmarshalingV3 = true
+		got, err := openapi.MarshalJSON()
+		if err != nil {
+			t.Fatal(err)
+		}
+		if err := jsontesting.JsonCompare(want, got); err != nil {
+			t.Errorf("fuzzed marshal doesn't match: %v", err)
+		}
+	}
+}
+
+func TestOpenAPIV3SerializeStable(t *testing.T) {
+	swagFile, err := os.Open("./testdata/appsv1spec.json")
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer swagFile.Close()
+	originalJSON, err := io.ReadAll(swagFile)
+	if err != nil {
+		t.Fatal(err)
+	}
+	var openapi *OpenAPI
+	if err := json.Unmarshal(originalJSON, &openapi); err != nil {
+		t.Fatal(err)
+	}
+
+	internal.UseOptimizedJSONUnmarshalingV3 = true
+	for i := 0; i < 5; i++ {
+		t.Run(fmt.Sprintf("%d", i), func(t *testing.T) {
+			want, err := openapi.MarshalJSON()
+			if err != nil {
+				t.Fatal(err)
+			}
+			got, err := openapi.MarshalJSON()
+			if err != nil {
+				t.Fatal(err)
+			}
+			if err := jsontesting.JsonCompare(want, got); err != nil {
+				t.Errorf("marshal doesn't match: %v", err)
+			}
+		})
+	}
+}
+
 func BenchmarkOpenAPIV3Deserialize(b *testing.B) {
 	benchcases := []struct {
 		file string
@@ -142,3 +232,61 @@ func BenchmarkOpenAPIV3Deserialize(b *testing.B) {
 		})
 	}
 }
+
+func BenchmarkOpenAPIV3Serialize(b *testing.B) {
+	benchcases := []struct {
+		file string
+	}{
+		{
+			file: "appsv1spec.json",
+		},
+		{
+			file: "authorizationv1spec.json",
+		},
+	}
+	for _, bc := range benchcases {
+		swagFile, err := os.Open("./testdata/" + bc.file)
+		if err != nil {
+			b.Fatal(err)
+		}
+		defer swagFile.Close()
+		originalJSON, err := io.ReadAll(swagFile)
+		if err != nil {
+			b.Fatal(err)
+		}
+		var openapi *OpenAPI
+		if err := json.Unmarshal(originalJSON, &openapi); err != nil {
+			b.Fatal(err)
+		}
+		b.ResetTimer()
+		b.Run(fmt.Sprintf("%s jsonv1", bc.file), func(b2 *testing.B) {
+			b2.ReportAllocs()
+			internal.UseOptimizedJSONMarshalingV3 = false
+			for i := 0; i < b2.N; i++ {
+				if _, err := json.Marshal(openapi); err != nil {
+					b2.Fatal(err)
+				}
+			}
+		})
+
+		b.Run(fmt.Sprintf("%s jsonv2 via jsonv1 full spec", bc.file), func(b2 *testing.B) {
+			b2.ReportAllocs()
+			internal.UseOptimizedJSONMarshalingV3 = true
+			for i := 0; i < b2.N; i++ {
+				if _, err := json.Marshal(openapi); err != nil {
+					b2.Fatal(err)
+				}
+			}
+		})
+
+		b.Run("jsonv2", func(b2 *testing.B) {
+			b2.ReportAllocs()
+			internal.UseOptimizedJSONMarshalingV3 = true
+			for i := 0; i < b2.N; i++ {
+				if _, err := openapi.MarshalJSON(); err != nil {
+					b2.Fatal(err)
+				}
+			}
+		})
+	}
+}

pkg/spec3/encoding.go

@@ -32,6 +32,9 @@ type Encoding struct {
 
 // MarshalJSON is a custom marshal function that knows how to encode Encoding as JSON
 func (e *Encoding) MarshalJSON() ([]byte, error) {
+	if internal.UseOptimizedJSONMarshalingV3 {
+		return internal.DeterministicMarshal(e)
+	}
 	b1, err := json.Marshal(e.EncodingProps)
 	if err != nil {
 		return nil, err
@@ -43,6 +46,16 @@ func (e *Encoding) MarshalJSON() ([]byte, error) {
 	return swag.ConcatJSON(b1, b2), nil
 }
 
+func (e *Encoding) MarshalNextJSON(opts jsonv2.MarshalOptions, enc *jsonv2.Encoder) error {
+	var x struct {
+		EncodingProps encodingPropsOmitZero `json:",inline"`
+		spec.Extensions
+	}
+	x.Extensions = internal.SanitizeExtensions(e.Extensions)
+	x.EncodingProps = encodingPropsOmitZero(e.EncodingProps)
+	return opts.MarshalNext(enc, x)
+}
+
 func (e *Encoding) UnmarshalJSON(data []byte) error {
 	if internal.UseOptimizedJSONUnmarshalingV3 {
 		return jsonv2.Unmarshal(data, e)
@@ -82,3 +95,11 @@ type EncodingProps struct {
 	// AllowReserved determines whether the parameter value SHOULD allow reserved characters, as defined by RFC3986
 	AllowReserved bool `json:"allowReserved,omitempty"`
 }
+
+type encodingPropsOmitZero struct {
+	ContentType   string             `json:"contentType,omitempty"`
+	Headers       map[string]*Header `json:"headers,omitempty"`
+	Style         string             `json:"style,omitempty"`
+	Explode       bool               `json:"explode,omitzero"`
+	AllowReserved bool               `json:"allowReserved,omitzero"`
+}

pkg/spec3/example.go

@@ -36,6 +36,9 @@ type Example struct {
 
 // MarshalJSON is a custom marshal function that knows how to encode RequestBody as JSON
 func (e *Example) MarshalJSON() ([]byte, error) {
+	if internal.UseOptimizedJSONMarshalingV3 {
+		return internal.DeterministicMarshal(e)
+	}
 	b1, err := json.Marshal(e.Refable)
 	if err != nil {
 		return nil, err
@@ -50,6 +53,17 @@ func (e *Example) MarshalJSON() ([]byte, error) {
 	}
 	return swag.ConcatJSON(b1, b2, b3), nil
 }
+func (e *Example) MarshalNextJSON(opts jsonv2.MarshalOptions, enc *jsonv2.Encoder) error {
+	var x struct {
+		Ref          string `json:"$ref,omitempty"`
+		ExampleProps `json:",inline"`
+		spec.Extensions
+	}
+	x.Ref = e.Refable.Ref.String()
+	x.Extensions = internal.SanitizeExtensions(e.Extensions)
+	x.ExampleProps = e.ExampleProps
+	return opts.MarshalNext(enc, x)
+}
 
 func (e *Example) UnmarshalJSON(data []byte) error {
 	if internal.UseOptimizedJSONUnmarshalingV3 {

pkg/spec3/external_documentation.go

@@ -39,6 +39,9 @@ type ExternalDocumentationProps struct {
 
 // MarshalJSON is a custom marshal function that knows how to encode Responses as JSON
 func (e *ExternalDocumentation) MarshalJSON() ([]byte, error) {
+	if internal.UseOptimizedJSONMarshalingV3 {
+		return internal.DeterministicMarshal(e)
+	}
 	b1, err := json.Marshal(e.ExternalDocumentationProps)
 	if err != nil {
 		return nil, err
@@ -50,6 +53,16 @@ func (e *ExternalDocumentation) MarshalJSON() ([]byte, error) {
 	return swag.ConcatJSON(b1, b2), nil
 }
 
+func (e *ExternalDocumentation) MarshalNextJSON(opts jsonv2.MarshalOptions, enc *jsonv2.Encoder) error {
+	var x struct {
+		ExternalDocumentationProps `json:",inline"`
+		spec.Extensions
+	}
+	x.Extensions = internal.SanitizeExtensions(e.Extensions)
+	x.ExternalDocumentationProps = e.ExternalDocumentationProps
+	return opts.MarshalNext(enc, x)
+}
+
 func (e *ExternalDocumentation) UnmarshalJSON(data []byte) error {
 	if internal.UseOptimizedJSONUnmarshalingV3 {
 		return jsonv2.Unmarshal(data, e)

pkg/spec3/fuzz.go

@@ -169,6 +169,21 @@ var OpenAPIV3FuzzFuncs []interface{} = []interface{}{
 		c.Fuzz(&v.ResponseProps)
 		c.Fuzz(&v.VendorExtensible)
 	},
+	func(v *Operation, c fuzz.Continue) {
+		c.FuzzNoCustom(v)
+		// Do not fuzz null values into the array.
+		for i, val := range v.SecurityRequirement {
+			if val == nil {
+				v.SecurityRequirement[i] = make(map[string][]string)
+			}
+
+			for k, v := range val {
+				if v == nil {
+					val[k] = make([]string, 0)
+				}
+			}
+		}
+	},
 	func(v *spec.Extensions, c fuzz.Continue) {
 		numChildren := c.Intn(5)
 		for i := 0; i < numChildren; i++ {

pkg/spec3/header.go

@@ -36,6 +36,9 @@ type Header struct {
 
 // MarshalJSON is a custom marshal function that knows how to encode Header as JSON
 func (h *Header) MarshalJSON() ([]byte, error) {
+	if internal.UseOptimizedJSONMarshalingV3 {
+		return internal.DeterministicMarshal(h)
+	}
 	b1, err := json.Marshal(h.Refable)
 	if err != nil {
 		return nil, err
@@ -51,6 +54,18 @@ func (h *Header) MarshalJSON() ([]byte, error) {
 	return swag.ConcatJSON(b1, b2, b3), nil
 }
 
+func (h *Header) MarshalNextJSON(opts jsonv2.MarshalOptions, enc *jsonv2.Encoder) error {
+	var x struct {
+		Ref         string              `json:"$ref,omitempty"`
+		HeaderProps headerPropsOmitZero `json:",inline"`
+		spec.Extensions
+	}
+	x.Ref = h.Refable.Ref.String()
+	x.Extensions = internal.SanitizeExtensions(h.Extensions)
+	x.HeaderProps = headerPropsOmitZero(h.HeaderProps)
+	return opts.MarshalNext(enc, x)
+}
+
 func (h *Header) UnmarshalJSON(data []byte) error {
 	if internal.UseOptimizedJSONUnmarshalingV3 {
 		return jsonv2.Unmarshal(data, h)
@@ -109,3 +124,19 @@ type HeaderProps struct {
 	// Examples of the header
 	Examples map[string]*Example `json:"examples,omitempty"`
 }
+
+// Marshaling structure only, always edit along with corresponding
+// struct (or compilation will fail).
+type headerPropsOmitZero struct {
+	Description     string                `json:"description,omitempty"`
+	Required        bool                  `json:"required,omitzero"`
+	Deprecated      bool                  `json:"deprecated,omitzero"`
+	AllowEmptyValue bool                  `json:"allowEmptyValue,omitzero"`
+	Style           string                `json:"style,omitempty"`
+	Explode         bool                  `json:"explode,omitzero"`
+	AllowReserved   bool                  `json:"allowReserved,omitzero"`
+	Schema          *spec.Schema          `json:"schema,omitzero"`
+	Content         map[string]*MediaType `json:"content,omitempty"`
+	Example         interface{}           `json:"example,omitempty"`
+	Examples        map[string]*Example   `json:"examples,omitempty"`
+}

pkg/spec3/media_type.go

@@ -35,6 +35,9 @@ type MediaType struct {
 
 // MarshalJSON is a custom marshal function that knows how to encode MediaType as JSON
 func (m *MediaType) MarshalJSON() ([]byte, error) {
+	if internal.UseOptimizedJSONMarshalingV3 {
+		return internal.DeterministicMarshal(m)
+	}
 	b1, err := json.Marshal(m.MediaTypeProps)
 	if err != nil {
 		return nil, err
@@ -46,6 +49,16 @@ func (m *MediaType) MarshalJSON() ([]byte, error) {
 	return swag.ConcatJSON(b1, b2), nil
 }
 
+func (e *MediaType) MarshalNextJSON(opts jsonv2.MarshalOptions, enc *jsonv2.Encoder) error {
+	var x struct {
+		MediaTypeProps mediaTypePropsOmitZero `json:",inline"`
+		spec.Extensions
+	}
+	x.Extensions = internal.SanitizeExtensions(e.Extensions)
+	x.MediaTypeProps = mediaTypePropsOmitZero(e.MediaTypeProps)
+	return opts.MarshalNext(enc, x)
+}
+
 func (m *MediaType) UnmarshalJSON(data []byte) error {
 	if internal.UseOptimizedJSONUnmarshalingV3 {
 		return jsonv2.Unmarshal(data, m)
@@ -84,3 +97,10 @@ type MediaTypeProps struct {
 	// A map between a property name and its encoding information. The key, being the property name, MUST exist in the schema as a property. The encoding object SHALL only apply to requestBody objects when the media type is multipart or application/x-www-form-urlencoded
 	Encoding map[string]*Encoding `json:"encoding,omitempty"`
 }
+
+type mediaTypePropsOmitZero struct {
+	Schema   *spec.Schema         `json:"schema,omitzero"`
+	Example  interface{}          `json:"example,omitempty"`
+	Examples map[string]*Example  `json:"examples,omitempty"`
+	Encoding map[string]*Encoding `json:"encoding,omitempty"`
+}