| // Copyright 2018 The Go Authors. All rights reserved. |
| // Use of this source code is governed by a BSD-style |
| // license that can be found in the LICENSE file. |
| |
| package protoreflect |
| |
| import "github.com/golang/protobuf/v2/internal/encoding/wire" |
| |
| // Enum is a reflection interface for a concrete enum value, |
| // which provides type information and a getter for the enum number. |
| // Enum does not provide a mutable API since enums are commonly backed by |
| // Go constants, which are not addressable. |
| type Enum interface { |
| Type() EnumType |
| |
| // Number returns the enum value as an integer. |
| Number() EnumNumber |
| } |
| |
| // Message is a reflective interface for a concrete message value, |
| // which provides type information and getters/setters for individual fields. |
| // |
| // Concrete types may implement interfaces defined in proto/protoiface, |
| // which provide specialized, performant implementations of high-level |
| // operations such as Marshal and Unmarshal. |
| type Message interface { |
| Type() MessageType |
| |
| // KnownFields returns an interface to access/mutate known fields. |
| KnownFields() KnownFields |
| |
| // UnknownFields returns an interface to access/mutate unknown fields. |
| UnknownFields() UnknownFields |
| |
| // Interface unwraps the message reflection interface and |
| // returns the underlying proto.Message interface. |
| Interface() ProtoMessage |
| } |
| |
| // KnownFields provides accessor and mutator methods for known fields. |
| // |
| // Each field Value can either be a scalar, Message, List, or Map. |
| // The field is a List or Map if FieldDescriptor.Cardinality is Repeated and |
| // a Map if and only if FieldDescriptor.IsMap is true. The scalar type or |
| // underlying repeated element type is determined by the FieldDescriptor.Kind. |
| // See Value for a list of Go types associated with each Kind. |
| // |
| // Field extensions are handled as known fields once the extension type has been |
| // registered with KnownFields.ExtensionTypes. |
| // |
| // Len, Has, Get, Range, and ExtensionTypes are safe for concurrent use. |
| type KnownFields interface { |
| // Len reports the number of fields that are populated. |
| Len() int |
| |
| // Has reports whether a field is populated. |
| // |
| // Some fields have the property of nullability where it is possible to |
| // distinguish between the default value of a field and whether the field |
| // was explicitly populated with the default value. Only scalars in proto2, |
| // member fields of a oneof, and singular messages are nullable. |
| // |
| // A nullable field is populated only if explicitly set. |
| // A scalar field in proto3 is populated if it contains a non-zero value. |
| // A repeated field is populated only if it is non-empty. |
| Has(FieldNumber) bool |
| |
| // Get retrieves the value for a field with the given field number. |
| // If the field is unpopulated, it returns the default value for scalars, |
| // a mutable empty List for empty repeated fields, a mutable empty Map for |
| // empty map fields, and an invalid value for message fields. |
| // If the field is unknown (does not appear in MessageDescriptor.Fields |
| // or ExtensionFieldTypes), it returns an invalid value. |
| Get(FieldNumber) Value |
| |
| // Set stores the value for a field with the given field number. |
| // Setting a field belonging to a oneof implicitly clears any other field |
| // that may be currently set by the same oneof. |
| // |
| // When setting a composite type, it is unspecified whether the set |
| // value aliases the source's memory in any way. |
| // |
| // It panics if the field number does not correspond with a known field |
| // in MessageDescriptor.Fields or an extension field in ExtensionTypes. |
| Set(FieldNumber, Value) |
| |
| // TODO: Document memory aliasing behavior when a field is cleared? |
| // For example, if Mutable is called later, can it reuse memory? |
| |
| // Clear clears the field such that a subsequent call to Has reports false. |
| // The operation does nothing if the field number does not correspond with |
| // a known field or extension field. |
| Clear(FieldNumber) |
| |
| // WhichOneof reports which field within the named oneof is populated. |
| // It returns 0 if the oneof does not exist or no fields are populated. |
| WhichOneof(Name) FieldNumber |
| |
| // Range iterates over every populated field in an undefined order, |
| // calling f for each field number and value encountered. |
| // Range calls f Len times unless f returns false, which stops iteration. |
| // While iterating, mutating operations through Set, Clear, or Mutable |
| // may only be performed on the current field number. |
| Range(f func(FieldNumber, Value) bool) |
| |
| // NewMessage returns a newly allocated empty message assignable to |
| // the field of the given number. |
| // It panics if the field is not a singular message. |
| NewMessage(FieldNumber) Message |
| |
| // ExtensionTypes are extension field types that are known by this |
| // specific message instance. |
| ExtensionTypes() ExtensionFieldTypes |
| } |
| |
| // UnknownFields are a list of unknown or unparsed fields and may contain |
| // field numbers corresponding with defined fields or extension fields. |
| // The ordering of fields is maintained for fields of the same field number. |
| // However, the relative ordering of fields with different field numbers |
| // is undefined. |
| // |
| // Len, Get, and Range are safe for concurrent use. |
| type UnknownFields interface { |
| // Len reports the number of fields that are populated. |
| Len() int |
| |
| // Get retrieves the raw bytes of fields with the given field number. |
| // It returns an empty RawFields if there are no populated fields. |
| // |
| // The caller must not mutate the content of the retrieved RawFields. |
| Get(FieldNumber) RawFields |
| |
| // Set stores the raw bytes of fields with the given field number. |
| // The RawFields must be valid and correspond with the given field number; |
| // an implementation may panic if the fields are invalid. |
| // An empty RawFields may be passed to clear the fields. |
| // |
| // The caller must not mutate the content of the RawFields being stored. |
| Set(FieldNumber, RawFields) |
| |
| // Range iterates over every populated field in an undefined order, |
| // calling f for each field number and raw field value encountered. |
| // Range calls f Len times unless f returns false, which stops iteration. |
| // While iterating, mutating operations through Set may only be performed |
| // on the current field number. |
| // |
| // While the iteration order is undefined, it is deterministic. |
| // It is recommended, but not required, that fields be presented |
| // in the order that they were encountered in the wire data. |
| Range(f func(FieldNumber, RawFields) bool) |
| |
| // TODO: Should IsSupported be renamed as ReadOnly? |
| // TODO: Should IsSupported panic on Set instead of silently ignore? |
| |
| // IsSupported reports whether this message supports unknown fields. |
| // If false, UnknownFields ignores all Set operations. |
| IsSupported() bool |
| } |
| |
| // RawFields is the raw bytes for an ordered sequence of fields. |
| // Each field contains both the tag (representing field number and wire type), |
| // and also the wire data itself. |
| // |
| // Once stored, the content of a RawFields must be treated as immutable. |
| // The capacity of RawFields may be treated as mutable only for the use-case of |
| // appending additional data to store back into UnknownFields. |
| type RawFields []byte |
| |
| // IsValid reports whether RawFields is syntactically correct wire format. |
| // All fields must belong to the same field number. |
| func (b RawFields) IsValid() bool { |
| var want FieldNumber |
| for len(b) > 0 { |
| got, _, n := wire.ConsumeField(b) |
| if n < 0 || (want > 0 && got != want) { |
| return false |
| } |
| want = got |
| b = b[n:] |
| } |
| return true |
| } |
| |
| // ExtensionFieldTypes are the extension field types that this message instance |
| // has been extended with. |
| // |
| // Len, Get, and Range are safe for concurrent use. |
| type ExtensionFieldTypes interface { |
| // Len reports the number of field extensions. |
| Len() int |
| |
| // Register stores an ExtensionType. |
| // The ExtensionType.ExtendedType must match the containing message type |
| // and the field number must be within the valid extension ranges |
| // (see MessageDescriptor.ExtensionRanges). |
| // It panics if the extension has already been registered (i.e., |
| // a conflict by number or by full name). |
| Register(ExtensionType) |
| |
| // Remove removes the ExtensionType. |
| // It panics if a value for this extension field is still populated. |
| // The operation does nothing if there is no associated type to remove. |
| Remove(ExtensionType) |
| |
| // ByNumber looks up an extension by field number. |
| // It returns nil if not found. |
| ByNumber(FieldNumber) ExtensionType |
| |
| // ByName looks up an extension field by full name. |
| // It returns nil if not found. |
| ByName(FullName) ExtensionType |
| |
| // Range iterates over every registered field in an undefined order, |
| // calling f for each extension descriptor encountered. |
| // Range calls f Len times unless f returns false, which stops iteration. |
| // While iterating, mutating operations through Remove may only |
| // be performed on the current descriptor. |
| Range(f func(ExtensionType) bool) |
| } |
| |
| // List is an ordered list. Every element is considered populated |
| // (i.e., Get never provides and Set never accepts invalid Values). |
| // The element Value type is determined by the associated FieldDescriptor.Kind |
| // and cannot be a Map or List. |
| // |
| // Len and Get are safe for concurrent use. |
| type List interface { |
| // Len reports the number of entries in the List. |
| // Get, Set, Mutable, and Truncate panic with out of bound indexes. |
| Len() int |
| |
| // Get retrieves the value at the given index. |
| Get(int) Value |
| |
| // Set stores a value for the given index. |
| // |
| // When setting a composite type, it is unspecified whether the set |
| // value aliases the source's memory in any way. |
| Set(int, Value) |
| |
| // Append appends the provided value to the end of the list. |
| // |
| // When appending a composite type, it is unspecified whether the appended |
| // value aliases the source's memory in any way. |
| Append(Value) |
| |
| // TODO: Should truncate accept two indexes similar to slicing? |
| |
| // Truncate truncates the list to a smaller length. |
| Truncate(int) |
| |
| // NewMessage returns a newly allocated empty message assignable to a list entry. |
| // It panics if the list entry type is not a message. |
| NewMessage() Message |
| } |
| |
| // Map is an unordered, associative map. Only elements within the map |
| // is considered populated. The entry Value type is determined by the associated |
| // FieldDescripto.Kind and cannot be a Map or List. |
| // |
| // Len, Has, Get, and Range are safe for concurrent use. |
| type Map interface { |
| // Len reports the number of elements in the map. |
| Len() int |
| |
| // Has reports whether an entry with the given key is in the map. |
| Has(MapKey) bool |
| |
| // Get retrieves the value for an entry with the given key. |
| // It returns an invalid value for non-existent entries. |
| Get(MapKey) Value |
| |
| // Set stores the value for an entry with the given key. |
| // |
| // When setting a composite type, it is unspecified whether the set |
| // value aliases the source's memory in any way. |
| // |
| // It panics if either the key or value are invalid. |
| Set(MapKey, Value) |
| |
| // Clear clears the entry associated with they given key. |
| // The operation does nothing if there is no entry associated with the key. |
| Clear(MapKey) |
| |
| // Range iterates over every map entry in an undefined order, |
| // calling f for each key and value encountered. |
| // Range calls f Len times unless f returns false, which stops iteration. |
| // While iterating, mutating operations through Set, Clear, or Mutable |
| // may only be performed on the current map key. |
| Range(f func(MapKey, Value) bool) |
| |
| // NewMessage returns a newly allocated empty message assignable to a map value. |
| // It panics if the map value type is not a message. |
| NewMessage() Message |
| } |