| /* |
| Copyright 2014 The Kubernetes Authors. |
| |
| Licensed under the Apache License, Version 2.0 (the "License"); |
| you may not use this file except in compliance with the License. |
| You may obtain a copy of the License at |
| |
| http://www.apache.org/licenses/LICENSE-2.0 |
| |
| Unless required by applicable law or agreed to in writing, software |
| distributed under the License is distributed on an "AS IS" BASIS, |
| WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| See the License for the specific language governing permissions and |
| limitations under the License. |
| */ |
| |
| package runtime |
| |
| import ( |
| "io" |
| "net/url" |
| |
| "k8s.io/apimachinery/pkg/runtime/schema" |
| ) |
| |
| const ( |
| // APIVersionInternal may be used if you are registering a type that should not |
| // be considered stable or serialized - it is a convention only and has no |
| // special behavior in this package. |
| APIVersionInternal = "__internal" |
| ) |
| |
| // GroupVersioner refines a set of possible conversion targets into a single option. |
| type GroupVersioner interface { |
| // KindForGroupVersionKinds returns a desired target group version kind for the given input, or returns ok false if no |
| // target is known. In general, if the return target is not in the input list, the caller is expected to invoke |
| // Scheme.New(target) and then perform a conversion between the current Go type and the destination Go type. |
| // Sophisticated implementations may use additional information about the input kinds to pick a destination kind. |
| KindForGroupVersionKinds(kinds []schema.GroupVersionKind) (target schema.GroupVersionKind, ok bool) |
| // Identifier returns string representation of the object. |
| // Identifiers of two different encoders should be equal only if for every input |
| // kinds they return the same result. |
| Identifier() string |
| } |
| |
| // Identifier represents an identifier. |
| // Identitier of two different objects should be equal if and only if for every |
| // input the output they produce is exactly the same. |
| type Identifier string |
| |
| // Encoder writes objects to a serialized form |
| type Encoder interface { |
| // Encode writes an object to a stream. Implementations may return errors if the versions are |
| // incompatible, or if no conversion is defined. |
| Encode(obj Object, w io.Writer) error |
| // Identifier returns an identifier of the encoder. |
| // Identifiers of two different encoders should be equal if and only if for every input |
| // object it will be encoded to the same representation by both of them. |
| // |
| // Identifier is inteted for use with CacheableObject#CacheEncode method. In order to |
| // correctly handle CacheableObject, Encode() method should look similar to below, where |
| // doEncode() is the encoding logic of implemented encoder: |
| // func (e *MyEncoder) Encode(obj Object, w io.Writer) error { |
| // if co, ok := obj.(CacheableObject); ok { |
| // return co.CacheEncode(e.Identifier(), e.doEncode, w) |
| // } |
| // return e.doEncode(obj, w) |
| // } |
| Identifier() Identifier |
| } |
| |
| // Decoder attempts to load an object from data. |
| type Decoder interface { |
| // Decode attempts to deserialize the provided data using either the innate typing of the scheme or the |
| // default kind, group, and version provided. It returns a decoded object as well as the kind, group, and |
| // version from the serialized data, or an error. If into is non-nil, it will be used as the target type |
| // and implementations may choose to use it rather than reallocating an object. However, the object is not |
| // guaranteed to be populated. The returned object is not guaranteed to match into. If defaults are |
| // provided, they are applied to the data by default. If no defaults or partial defaults are provided, the |
| // type of the into may be used to guide conversion decisions. |
| Decode(data []byte, defaults *schema.GroupVersionKind, into Object) (Object, *schema.GroupVersionKind, error) |
| } |
| |
| // Serializer is the core interface for transforming objects into a serialized format and back. |
| // Implementations may choose to perform conversion of the object, but no assumptions should be made. |
| type Serializer interface { |
| Encoder |
| Decoder |
| } |
| |
| // Codec is a Serializer that deals with the details of versioning objects. It offers the same |
| // interface as Serializer, so this is a marker to consumers that care about the version of the objects |
| // they receive. |
| type Codec Serializer |
| |
| // ParameterCodec defines methods for serializing and deserializing API objects to url.Values and |
| // performing any necessary conversion. Unlike the normal Codec, query parameters are not self describing |
| // and the desired version must be specified. |
| type ParameterCodec interface { |
| // DecodeParameters takes the given url.Values in the specified group version and decodes them |
| // into the provided object, or returns an error. |
| DecodeParameters(parameters url.Values, from schema.GroupVersion, into Object) error |
| // EncodeParameters encodes the provided object as query parameters or returns an error. |
| EncodeParameters(obj Object, to schema.GroupVersion) (url.Values, error) |
| } |
| |
| // Framer is a factory for creating readers and writers that obey a particular framing pattern. |
| type Framer interface { |
| NewFrameReader(r io.ReadCloser) io.ReadCloser |
| NewFrameWriter(w io.Writer) io.Writer |
| } |
| |
| // SerializerInfo contains information about a specific serialization format |
| type SerializerInfo struct { |
| // MediaType is the value that represents this serializer over the wire. |
| MediaType string |
| // MediaTypeType is the first part of the MediaType ("application" in "application/json"). |
| MediaTypeType string |
| // MediaTypeSubType is the second part of the MediaType ("json" in "application/json"). |
| MediaTypeSubType string |
| // EncodesAsText indicates this serializer can be encoded to UTF-8 safely. |
| EncodesAsText bool |
| // Serializer is the individual object serializer for this media type. |
| Serializer Serializer |
| // PrettySerializer, if set, can serialize this object in a form biased towards |
| // readability. |
| PrettySerializer Serializer |
| // StreamSerializer, if set, describes the streaming serialization format |
| // for this media type. |
| StreamSerializer *StreamSerializerInfo |
| } |
| |
| // StreamSerializerInfo contains information about a specific stream serialization format |
| type StreamSerializerInfo struct { |
| // EncodesAsText indicates this serializer can be encoded to UTF-8 safely. |
| EncodesAsText bool |
| // Serializer is the top level object serializer for this type when streaming |
| Serializer |
| // Framer is the factory for retrieving streams that separate objects on the wire |
| Framer |
| } |
| |
| // NegotiatedSerializer is an interface used for obtaining encoders, decoders, and serializers |
| // for multiple supported media types. This would commonly be accepted by a server component |
| // that performs HTTP content negotiation to accept multiple formats. |
| type NegotiatedSerializer interface { |
| // SupportedMediaTypes is the media types supported for reading and writing single objects. |
| SupportedMediaTypes() []SerializerInfo |
| |
| // EncoderForVersion returns an encoder that ensures objects being written to the provided |
| // serializer are in the provided group version. |
| EncoderForVersion(serializer Encoder, gv GroupVersioner) Encoder |
| // DecoderForVersion returns a decoder that ensures objects being read by the provided |
| // serializer are in the provided group version by default. |
| DecoderToVersion(serializer Decoder, gv GroupVersioner) Decoder |
| } |
| |
| // ClientNegotiator handles turning an HTTP content type into the appropriate encoder. |
| // Use NewClientNegotiator or NewVersionedClientNegotiator to create this interface from |
| // a NegotiatedSerializer. |
| type ClientNegotiator interface { |
| // Encoder returns the appropriate encoder for the provided contentType (e.g. application/json) |
| // and any optional mediaType parameters (e.g. pretty=1), or an error. If no serializer is found |
| // a NegotiateError will be returned. The current client implementations consider params to be |
| // optional modifiers to the contentType and will ignore unrecognized parameters. |
| Encoder(contentType string, params map[string]string) (Encoder, error) |
| // Decoder returns the appropriate decoder for the provided contentType (e.g. application/json) |
| // and any optional mediaType parameters (e.g. pretty=1), or an error. If no serializer is found |
| // a NegotiateError will be returned. The current client implementations consider params to be |
| // optional modifiers to the contentType and will ignore unrecognized parameters. |
| Decoder(contentType string, params map[string]string) (Decoder, error) |
| // StreamDecoder returns the appropriate stream decoder for the provided contentType (e.g. |
| // application/json) and any optional mediaType parameters (e.g. pretty=1), or an error. If no |
| // serializer is found a NegotiateError will be returned. The Serializer and Framer will always |
| // be returned if a Decoder is returned. The current client implementations consider params to be |
| // optional modifiers to the contentType and will ignore unrecognized parameters. |
| StreamDecoder(contentType string, params map[string]string) (Decoder, Serializer, Framer, error) |
| } |
| |
| // StorageSerializer is an interface used for obtaining encoders, decoders, and serializers |
| // that can read and write data at rest. This would commonly be used by client tools that must |
| // read files, or server side storage interfaces that persist restful objects. |
| type StorageSerializer interface { |
| // SupportedMediaTypes are the media types supported for reading and writing objects. |
| SupportedMediaTypes() []SerializerInfo |
| |
| // UniversalDeserializer returns a Serializer that can read objects in multiple supported formats |
| // by introspecting the data at rest. |
| UniversalDeserializer() Decoder |
| |
| // EncoderForVersion returns an encoder that ensures objects being written to the provided |
| // serializer are in the provided group version. |
| EncoderForVersion(serializer Encoder, gv GroupVersioner) Encoder |
| // DecoderForVersion returns a decoder that ensures objects being read by the provided |
| // serializer are in the provided group version by default. |
| DecoderToVersion(serializer Decoder, gv GroupVersioner) Decoder |
| } |
| |
| // NestedObjectEncoder is an optional interface that objects may implement to be given |
| // an opportunity to encode any nested Objects / RawExtensions during serialization. |
| type NestedObjectEncoder interface { |
| EncodeNestedObjects(e Encoder) error |
| } |
| |
| // NestedObjectDecoder is an optional interface that objects may implement to be given |
| // an opportunity to decode any nested Objects / RawExtensions during serialization. |
| type NestedObjectDecoder interface { |
| DecodeNestedObjects(d Decoder) error |
| } |
| |
| /////////////////////////////////////////////////////////////////////////////// |
| // Non-codec interfaces |
| |
| type ObjectDefaulter interface { |
| // Default takes an object (must be a pointer) and applies any default values. |
| // Defaulters may not error. |
| Default(in Object) |
| } |
| |
| type ObjectVersioner interface { |
| ConvertToVersion(in Object, gv GroupVersioner) (out Object, err error) |
| } |
| |
| // ObjectConvertor converts an object to a different version. |
| type ObjectConvertor interface { |
| // Convert attempts to convert one object into another, or returns an error. This |
| // method does not mutate the in object, but the in and out object might share data structures, |
| // i.e. the out object cannot be mutated without mutating the in object as well. |
| // The context argument will be passed to all nested conversions. |
| Convert(in, out, context interface{}) error |
| // ConvertToVersion takes the provided object and converts it the provided version. This |
| // method does not mutate the in object, but the in and out object might share data structures, |
| // i.e. the out object cannot be mutated without mutating the in object as well. |
| // This method is similar to Convert() but handles specific details of choosing the correct |
| // output version. |
| ConvertToVersion(in Object, gv GroupVersioner) (out Object, err error) |
| ConvertFieldLabel(gvk schema.GroupVersionKind, label, value string) (string, string, error) |
| } |
| |
| // ObjectTyper contains methods for extracting the APIVersion and Kind |
| // of objects. |
| type ObjectTyper interface { |
| // ObjectKinds returns the all possible group,version,kind of the provided object, true if |
| // the object is unversioned, or an error if the object is not recognized |
| // (IsNotRegisteredError will return true). |
| ObjectKinds(Object) ([]schema.GroupVersionKind, bool, error) |
| // Recognizes returns true if the scheme is able to handle the provided version and kind, |
| // or more precisely that the provided version is a possible conversion or decoding |
| // target. |
| Recognizes(gvk schema.GroupVersionKind) bool |
| } |
| |
| // ObjectCreater contains methods for instantiating an object by kind and version. |
| type ObjectCreater interface { |
| New(kind schema.GroupVersionKind) (out Object, err error) |
| } |
| |
| // EquivalentResourceMapper provides information about resources that address the same underlying data as a specified resource |
| type EquivalentResourceMapper interface { |
| // EquivalentResourcesFor returns a list of resources that address the same underlying data as resource. |
| // If subresource is specified, only equivalent resources which also have the same subresource are included. |
| // The specified resource can be included in the returned list. |
| EquivalentResourcesFor(resource schema.GroupVersionResource, subresource string) []schema.GroupVersionResource |
| // KindFor returns the kind expected by the specified resource[/subresource]. |
| // A zero value is returned if the kind is unknown. |
| KindFor(resource schema.GroupVersionResource, subresource string) schema.GroupVersionKind |
| } |
| |
| // EquivalentResourceRegistry provides an EquivalentResourceMapper interface, |
| // and allows registering known resource[/subresource] -> kind |
| type EquivalentResourceRegistry interface { |
| EquivalentResourceMapper |
| // RegisterKindFor registers the existence of the specified resource[/subresource] along with its expected kind. |
| RegisterKindFor(resource schema.GroupVersionResource, subresource string, kind schema.GroupVersionKind) |
| } |
| |
| // ResourceVersioner provides methods for setting and retrieving |
| // the resource version from an API object. |
| type ResourceVersioner interface { |
| SetResourceVersion(obj Object, version string) error |
| ResourceVersion(obj Object) (string, error) |
| } |
| |
| // SelfLinker provides methods for setting and retrieving the SelfLink field of an API object. |
| type SelfLinker interface { |
| SetSelfLink(obj Object, selfLink string) error |
| SelfLink(obj Object) (string, error) |
| |
| // Knowing Name is sometimes necessary to use a SelfLinker. |
| Name(obj Object) (string, error) |
| // Knowing Namespace is sometimes necessary to use a SelfLinker |
| Namespace(obj Object) (string, error) |
| } |
| |
| // Object interface must be supported by all API types registered with Scheme. Since objects in a scheme are |
| // expected to be serialized to the wire, the interface an Object must provide to the Scheme allows |
| // serializers to set the kind, version, and group the object is represented as. An Object may choose |
| // to return a no-op ObjectKindAccessor in cases where it is not expected to be serialized. |
| type Object interface { |
| GetObjectKind() schema.ObjectKind |
| DeepCopyObject() Object |
| } |
| |
| // CacheableObject allows an object to cache its different serializations |
| // to avoid performing the same serialization multiple times. |
| type CacheableObject interface { |
| // CacheEncode writes an object to a stream. The <encode> function will |
| // be used in case of cache miss. The <encode> function takes ownership |
| // of the object. |
| // If CacheableObject is a wrapper, then deep-copy of the wrapped object |
| // should be passed to <encode> function. |
| // CacheEncode assumes that for two different calls with the same <id>, |
| // <encode> function will also be the same. |
| CacheEncode(id Identifier, encode func(Object, io.Writer) error, w io.Writer) error |
| // GetObject returns a deep-copy of an object to be encoded - the caller of |
| // GetObject() is the owner of returned object. The reason for making a copy |
| // is to avoid bugs, where caller modifies the object and forgets to copy it, |
| // thus modifying the object for everyone. |
| // The object returned by GetObject should be the same as the one that is supposed |
| // to be passed to <encode> function in CacheEncode method. |
| // If CacheableObject is a wrapper, the copy of wrapped object should be returned. |
| GetObject() Object |
| } |
| |
| // Unstructured objects store values as map[string]interface{}, with only values that can be serialized |
| // to JSON allowed. |
| type Unstructured interface { |
| Object |
| // NewEmptyInstance returns a new instance of the concrete type containing only kind/apiVersion and no other data. |
| // This should be called instead of reflect.New() for unstructured types because the go type alone does not preserve kind/apiVersion info. |
| NewEmptyInstance() Unstructured |
| // UnstructuredContent returns a non-nil map with this object's contents. Values may be |
| // []interface{}, map[string]interface{}, or any primitive type. Contents are typically serialized to |
| // and from JSON. SetUnstructuredContent should be used to mutate the contents. |
| UnstructuredContent() map[string]interface{} |
| // SetUnstructuredContent updates the object content to match the provided map. |
| SetUnstructuredContent(map[string]interface{}) |
| // IsList returns true if this type is a list or matches the list convention - has an array called "items". |
| IsList() bool |
| // EachListItem should pass a single item out of the list as an Object to the provided function. Any |
| // error should terminate the iteration. If IsList() returns false, this method should return an error |
| // instead of calling the provided function. |
| EachListItem(func(Object) error) error |
| } |