Implement Encoder.Identifier() method

staging/src/k8s.io/apimachinery/pkg/apis/meta/v1/unstructured/BUILD

@@ -44,6 +44,7 @@ go_library(
         "//staging/src/k8s.io/apimachinery/pkg/types:go_default_library",
         "//staging/src/k8s.io/apimachinery/pkg/util/json:go_default_library",
         "//staging/src/k8s.io/apimachinery/pkg/util/runtime:go_default_library",
+        "//vendor/k8s.io/klog:go_default_library",
     ],
 )
 

staging/src/k8s.io/apimachinery/pkg/apis/meta/v1/unstructured/helpers.go

@@ -27,6 +27,7 @@ import (
 	"k8s.io/apimachinery/pkg/runtime/schema"
 	"k8s.io/apimachinery/pkg/types"
 	"k8s.io/apimachinery/pkg/util/json"
+	"k8s.io/klog"
 )
 
 // NestedFieldCopy returns a deep copy of the value of a nested field.
@@ -329,6 +330,8 @@ var UnstructuredJSONScheme runtime.Codec = unstructuredJSONScheme{}
 
 type unstructuredJSONScheme struct{}
 
+const unstructuredJSONSchemeIdentifier runtime.Identifier = "unstructuredJSON"
+
 func (s unstructuredJSONScheme) Decode(data []byte, _ *schema.GroupVersionKind, obj runtime.Object) (runtime.Object, *schema.GroupVersionKind, error) {
 	var err error
 	if obj != nil {
@@ -373,6 +376,11 @@ func (unstructuredJSONScheme) Encode(obj runtime.Object, w io.Writer) error {
 	}
 }
 
+// Identifier implements runtime.Encoder interface.
+func (unstructuredJSONScheme) Identifier() runtime.Identifier {
+	return unstructuredJSONSchemeIdentifier
+}
+
 func (s unstructuredJSONScheme) decode(data []byte) (runtime.Object, error) {
 	type detector struct {
 		Items gojson.RawMessage
@@ -461,16 +469,28 @@ func (s unstructuredJSONScheme) decodeToList(data []byte, list *UnstructuredList
 }
 
 type jsonFallbackEncoder struct {
-	encoder runtime.Encoder
+	encoder    runtime.Encoder
+	identifier runtime.Identifier
 }
 
 func NewJSONFallbackEncoder(encoder runtime.Encoder) runtime.Encoder {
+	result := map[string]string{
+		"name": "fallback",
+		"base": string(encoder.Identifier()),
+	}
+	identifier, err := gojson.Marshal(result)
+	if err != nil {
+		klog.Fatalf("Failed marshaling identifier for jsonFallbackEncoder: %v", err)
+	}
 	return &jsonFallbackEncoder{
-		encoder: encoder,
+		encoder:    encoder,
+		identifier: runtime.Identifier(identifier),
 	}
 }
 
 func (c *jsonFallbackEncoder) Encode(obj runtime.Object, w io.Writer) error {
+	// There is no need to handle runtime.CacheableObject, as we only
+	// fallback to other encoders here.
 	err := c.encoder.Encode(obj, w)
 	if runtime.IsNotRegisteredError(err) {
 		switch obj.(type) {
@@ -480,3 +500,8 @@ func (c *jsonFallbackEncoder) Encode(obj runtime.Object, w io.Writer) error {
 	}
 	return err
 }
+
+// Identifier implements runtime.Encoder interface.
+func (c *jsonFallbackEncoder) Identifier() runtime.Identifier {
+	return c.identifier
+}

staging/src/k8s.io/apimachinery/pkg/runtime/codec.go

@@ -104,10 +104,17 @@ type NoopEncoder struct {
 
 var _ Serializer = NoopEncoder{}
 
+const noopEncoderIdentifier Identifier = "noop"
+
 func (n NoopEncoder) Encode(obj Object, w io.Writer) error {
 	return fmt.Errorf("encoding is not allowed for this codec: %v", reflect.TypeOf(n.Decoder))
 }
 
+// Identifier implements runtime.Encoder interface.
+func (n NoopEncoder) Identifier() Identifier {
+	return noopEncoderIdentifier
+}
+
 // NoopDecoder converts an Encoder to a Serializer or Codec for code that expects them but only uses encoding.
 type NoopDecoder struct {
 	Encoder
@@ -197,10 +204,30 @@ func (c *parameterCodec) EncodeParameters(obj Object, to schema.GroupVersion) (u
 type base64Serializer struct {
 	Encoder
 	Decoder
+
+	identifier Identifier
 }
 
 func NewBase64Serializer(e Encoder, d Decoder) Serializer {
-	return &base64Serializer{e, d}
+	return &base64Serializer{
+		Encoder:    e,
+		Decoder:    d,
+		identifier: identifier(e),
+	}
+}
+
+func identifier(e Encoder) Identifier {
+	result := map[string]string{
+		"name": "base64",
+	}
+	if e != nil {
+		result["encoder"] = string(e.Identifier())
+	}
+	identifier, err := json.Marshal(result)
+	if err != nil {
+		klog.Fatalf("Failed marshaling identifier for base64Serializer: %v", err)
+	}
+	return Identifier(identifier)
 }
 
 func (s base64Serializer) Encode(obj Object, stream io.Writer) error {
@@ -210,6 +237,11 @@ func (s base64Serializer) Encode(obj Object, stream io.Writer) error {
 	return err
 }
 
+// Identifier implements runtime.Encoder interface.
+func (s base64Serializer) Identifier() Identifier {
+	return s.identifier
+}
+
 func (s base64Serializer) Decode(data []byte, defaults *schema.GroupVersionKind, into Object) (Object, *schema.GroupVersionKind, error) {
 	out := make([]byte, base64.StdEncoding.DecodedLen(len(data)))
 	n, err := base64.StdEncoding.Decode(out, data)

staging/src/k8s.io/apimachinery/pkg/runtime/serializer/json/BUILD

@@ -36,6 +36,7 @@ go_library(
         "//staging/src/k8s.io/apimachinery/pkg/util/yaml:go_default_library",
         "//vendor/github.com/json-iterator/go:go_default_library",
         "//vendor/github.com/modern-go/reflect2:go_default_library",
+        "//vendor/k8s.io/klog:go_default_library",
         "//vendor/sigs.k8s.io/yaml:go_default_library",
     ],
 )

staging/src/k8s.io/apimachinery/pkg/runtime/serializer/json/json.go

@@ -31,6 +31,7 @@ import (
 	"k8s.io/apimachinery/pkg/runtime/serializer/recognizer"
 	"k8s.io/apimachinery/pkg/util/framer"
 	utilyaml "k8s.io/apimachinery/pkg/util/yaml"
+	"k8s.io/klog"
 )
 
 // NewSerializer creates a JSON serializer that handles encoding versioned objects into the proper JSON form. If typer
@@ -53,13 +54,28 @@ func NewYAMLSerializer(meta MetaFactory, creater runtime.ObjectCreater, typer ru
 // and are immutable.
 func NewSerializerWithOptions(meta MetaFactory, creater runtime.ObjectCreater, typer runtime.ObjectTyper, options SerializerOptions) *Serializer {
 	return &Serializer{
-		meta:    meta,
+		meta:       meta,
-		creater: creater,
+		creater:    creater,
-		typer:   typer,
+		typer:      typer,
-		options: options,
+		options:    options,
+		identifier: identifier(options),
 	}
 }
 
+// identifier computes Identifier of Encoder based on the given options.
+func identifier(options SerializerOptions) runtime.Identifier {
+	result := map[string]string{
+		"name":   "json",
+		"yaml":   strconv.FormatBool(options.Yaml),
+		"pretty": strconv.FormatBool(options.Pretty),
+	}
+	identifier, err := json.Marshal(result)
+	if err != nil {
+		klog.Fatalf("Failed marshaling identifier for json Serializer: %v", err)
+	}
+	return runtime.Identifier(identifier)
+}
+
 // SerializerOptions holds the options which are used to configure a JSON/YAML serializer.
 // example:
 // (1) To configure a JSON serializer, set `Yaml` to `false`.
@@ -85,6 +101,8 @@ type Serializer struct {
 	options SerializerOptions
 	creater runtime.ObjectCreater
 	typer   runtime.ObjectTyper
+
+	identifier runtime.Identifier
 }
 
 // Serializer implements Serializer
@@ -311,6 +329,11 @@ func (s *Serializer) Encode(obj runtime.Object, w io.Writer) error {
 	return encoder.Encode(obj)
 }
 
+// Identifier implements runtime.Encoder interface.
+func (s *Serializer) Identifier() runtime.Identifier {
+	return s.identifier
+}
+
 // RecognizesData implements the RecognizingDecoder interface.
 func (s *Serializer) RecognizesData(peek io.Reader) (ok, unknown bool, err error) {
 	if s.options.Yaml {

staging/src/k8s.io/apimachinery/pkg/runtime/serializer/protobuf/protobuf.go

@@ -86,6 +86,8 @@ type Serializer struct {
 var _ runtime.Serializer = &Serializer{}
 var _ recognizer.RecognizingDecoder = &Serializer{}
 
+const serializerIdentifier runtime.Identifier = "protobuf"
+
 // Decode attempts to convert the provided data into a protobuf message, extract the stored schema kind, apply the provided default
 // gvk, and then load that data into an object matching the desired schema kind or the provided into. If into is *runtime.Unknown,
 // the raw data will be extracted and no decoding will be performed. If into is not registered with the typer, then the object will
@@ -245,6 +247,11 @@ func (s *Serializer) Encode(obj runtime.Object, w io.Writer) error {
 	}
 }
 
+// Identifier implements runtime.Encoder interface.
+func (s *Serializer) Identifier() runtime.Identifier {
+	return serializerIdentifier
+}
+
 // RecognizesData implements the RecognizingDecoder interface.
 func (s *Serializer) RecognizesData(peek io.Reader) (bool, bool, error) {
 	prefix := make([]byte, 4)
@@ -321,6 +328,8 @@ type RawSerializer struct {
 
 var _ runtime.Serializer = &RawSerializer{}
 
+const rawSerializerIdentifier runtime.Identifier = "raw-protobuf"
+
 // Decode attempts to convert the provided data into a protobuf message, extract the stored schema kind, apply the provided default
 // gvk, and then load that data into an object matching the desired schema kind or the provided into. If into is *runtime.Unknown,
 // the raw data will be extracted and no decoding will be performed. If into is not registered with the typer, then the object will
@@ -460,6 +469,11 @@ func (s *RawSerializer) Encode(obj runtime.Object, w io.Writer) error {
 	}
 }
 
+// Identifier implements runtime.Encoder interface.
+func (s *RawSerializer) Identifier() runtime.Identifier {
+	return rawSerializerIdentifier
+}
+
 var LengthDelimitedFramer = lengthDelimitedFramer{}
 
 type lengthDelimitedFramer struct{}

staging/src/k8s.io/apimachinery/pkg/runtime/serializer/versioning/BUILD

@@ -31,6 +31,7 @@ go_library(
         "//staging/src/k8s.io/apimachinery/pkg/apis/meta/v1/unstructured:go_default_library",
         "//staging/src/k8s.io/apimachinery/pkg/runtime:go_default_library",
         "//staging/src/k8s.io/apimachinery/pkg/runtime/schema:go_default_library",
+        "//vendor/k8s.io/klog:go_default_library",
     ],
 )
 

staging/src/k8s.io/apimachinery/pkg/runtime/serializer/versioning/versioning.go

@@ -17,12 +17,14 @@ limitations under the License.
 package versioning
 
 import (
+	"encoding/json"
 	"io"
 	"reflect"
 
 	"k8s.io/apimachinery/pkg/apis/meta/v1/unstructured"
 	"k8s.io/apimachinery/pkg/runtime"
 	"k8s.io/apimachinery/pkg/runtime/schema"
+	"k8s.io/klog"
 )
 
 // NewDefaultingCodecForScheme is a convenience method for callers that are using a scheme.
@@ -62,6 +64,8 @@ func NewCodec(
 		encodeVersion: encodeVersion,
 		decodeVersion: decodeVersion,
 
+		identifier: identifier(encodeVersion, encoder),
+
 		originalSchemeName: originalSchemeName,
 	}
 	return internal
@@ -78,10 +82,30 @@ type codec struct {
 	encodeVersion runtime.GroupVersioner
 	decodeVersion runtime.GroupVersioner
 
+	identifier runtime.Identifier
+
 	// originalSchemeName is optional, but when filled in it holds the name of the scheme from which this codec originates
 	originalSchemeName string
 }
 
+// identifier computes Identifier of Encoder based on codec parameters.
+func identifier(encodeGV runtime.GroupVersioner, encoder runtime.Encoder) runtime.Identifier {
+	result := map[string]string{
+		"name": "versioning",
+	}
+	if encodeGV != nil {
+		result["encodeGV"] = encodeGV.Identifier()
+	}
+	if encoder != nil {
+		result["encoder"] = string(encoder.Identifier())
+	}
+	identifier, err := json.Marshal(result)
+	if err != nil {
+		klog.Fatalf("Failed marshaling identifier for codec: %v", err)
+	}
+	return runtime.Identifier(identifier)
+}
+
 // Decode attempts a decode of the object, then tries to convert it to the internal version. If into is provided and the decoding is
 // successful, the returned runtime.Object will be the value passed as into. Note that this may bypass conversion if you pass an
 // into that matches the serialized version.
@@ -230,3 +254,8 @@ func (c *codec) Encode(obj runtime.Object, w io.Writer) error {
 	// Conversion is responsible for setting the proper group, version, and kind onto the outgoing object
 	return c.encoder.Encode(out, w)
 }
+
+// Identifier implements runtime.Encoder interface.
+func (c *codec) Identifier() runtime.Identifier {
+	return c.identifier
+}

staging/src/k8s.io/apiserver/pkg/endpoints/discovery/BUILD

@@ -46,6 +46,7 @@ go_library(
         "//staging/src/k8s.io/apiserver/pkg/endpoints/handlers/negotiation:go_default_library",
         "//staging/src/k8s.io/apiserver/pkg/endpoints/handlers/responsewriters:go_default_library",
         "//vendor/github.com/emicklei/go-restful:go_default_library",
+        "//vendor/k8s.io/klog:go_default_library",
     ],
 )
 

staging/src/k8s.io/apiserver/pkg/endpoints/discovery/util.go

@@ -18,10 +18,12 @@ package discovery
 
 import (
 	"bytes"
+	"encoding/json"
 	"fmt"
 	"io"
 
 	"k8s.io/apimachinery/pkg/runtime"
+	"k8s.io/klog"
 )
 
 const APIGroupPrefix = "/apis"
@@ -36,6 +38,29 @@ func keepUnversioned(group string) bool {
 type stripVersionEncoder struct {
 	encoder    runtime.Encoder
 	serializer runtime.Serializer
+	identifier runtime.Identifier
+}
+
+func newStripVersionEncoder(e runtime.Encoder, s runtime.Serializer) runtime.Encoder {
+	return stripVersionEncoder{
+		encoder:    e,
+		serializer: s,
+		identifier: identifier(e),
+	}
+}
+
+func identifier(e runtime.Encoder) runtime.Identifier {
+	result := map[string]string{
+		"name": "stripVersion",
+	}
+	if e != nil {
+		result["encoder"] = string(e.Identifier())
+	}
+	identifier, err := json.Marshal(result)
+	if err != nil {
+		klog.Fatalf("Failed marshaling identifier for stripVersionEncoder: %v", err)
+	}
+	return runtime.Identifier(identifier)
 }
 
 func (c stripVersionEncoder) Encode(obj runtime.Object, w io.Writer) error {
@@ -54,6 +79,11 @@ func (c stripVersionEncoder) Encode(obj runtime.Object, w io.Writer) error {
 	return c.serializer.Encode(roundTrippedObj, w)
 }
 
+// Identifier implements runtime.Encoder interface.
+func (c stripVersionEncoder) Identifier() runtime.Identifier {
+	return c.identifier
+}
+
 // stripVersionNegotiatedSerializer will return stripVersionEncoder when
 // EncoderForVersion is called. See comments for stripVersionEncoder.
 type stripVersionNegotiatedSerializer struct {
@@ -69,5 +99,5 @@ func (n stripVersionNegotiatedSerializer) EncoderForVersion(encoder runtime.Enco
 		panic(fmt.Sprintf("Unable to extract serializer from %#v", encoder))
 	}
 	versioned := n.NegotiatedSerializer.EncoderForVersion(encoder, gv)
-	return stripVersionEncoder{versioned, serializer}
+	return newStripVersionEncoder(versioned, serializer)
 }

staging/src/k8s.io/apiserver/pkg/endpoints/handlers/responsewriters/writers_test.go

@@ -287,6 +287,10 @@ func (e *fakeEncoder) Encode(obj runtime.Object, w io.Writer) error {
 	return err
 }
 
+func (e *fakeEncoder) Identifier() runtime.Identifier {
+	return runtime.Identifier("fake")
+}
+
 func gzipContent(data []byte, level int) []byte {
 	buf := &bytes.Buffer{}
 	gw, err := gzip.NewWriterLevel(buf, level)

staging/src/k8s.io/cli-runtime/pkg/resource/scheme.go

@@ -58,6 +58,11 @@ func (dynamicCodec) Encode(obj runtime.Object, w io.Writer) error {
 	return unstructured.UnstructuredJSONScheme.Encode(obj, w)
 }
 
+// Identifier implements runtime.Encoder interface.
+func (dynamicCodec) Identifier() runtime.Identifier {
+	return unstructured.UnstructuredJSONScheme.Identifier()
+}
+
 // UnstructuredPlusDefaultContentConfig returns a rest.ContentConfig for dynamic types.  It includes enough codecs to act as a "normal"
 // serializer for the rest.client with options, status and the like.
 func UnstructuredPlusDefaultContentConfig() rest.ContentConfig {

staging/src/k8s.io/client-go/rest/config_test.go

@@ -190,6 +190,10 @@ func (c *fakeCodec) Encode(obj runtime.Object, stream io.Writer) error {
 	return nil
 }
 
+func (c *fakeCodec) Identifier() runtime.Identifier {
+	return runtime.Identifier("fake")
+}
+
 type fakeRoundTripper struct{}
 
 func (r *fakeRoundTripper) RoundTrip(*http.Request) (*http.Response, error) {