| // 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 provides interfaces to dynamically manipulate messages. |
| // |
| // This package includes type descriptors which describe the structure of types |
| // defined in proto source files and value interfaces which provide the |
| // ability to examine and manipulate the contents of messages. |
| // |
| // |
| // Protocol Buffer Descriptors |
| // |
| // Protobuf descriptors (e.g., EnumDescriptor or MessageDescriptor) |
| // are immutable objects that represent protobuf type information. |
| // They are wrappers around the messages declared in descriptor.proto. |
| // Protobuf descriptors alone lack any information regarding Go types. |
| // |
| // Enums and messages generated by this module implement Enum and ProtoMessage, |
| // where the Descriptor and ProtoReflect.Descriptor accessors respectively |
| // return the protobuf descriptor for the values. |
| // |
| // The protobuf descriptor interfaces are not meant to be implemented by |
| // user code since they might need to be extended in the future to support |
| // additions to the protobuf language. |
| // The "google.golang.org/protobuf/reflect/protodesc" package converts between |
| // google.protobuf.DescriptorProto messages and protobuf descriptors. |
| // |
| // |
| // Go Type Descriptors |
| // |
| // A type descriptor (e.g., EnumType or MessageType) is a constructor for |
| // a concrete Go type that represents the associated protobuf descriptor. |
| // There is commonly a one-to-one relationship between protobuf descriptors and |
| // Go type descriptors, but it can potentially be a one-to-many relationship. |
| // |
| // Enums and messages generated by this module implement Enum and ProtoMessage, |
| // where the Type and ProtoReflect.Type accessors respectively |
| // return the protobuf descriptor for the values. |
| // |
| // The "google.golang.org/protobuf/types/dynamicpb" package can be used to |
| // create Go type descriptors from protobuf descriptors. |
| // |
| // |
| // Value Interfaces |
| // |
| // The Enum and Message interfaces provide a reflective view over an |
| // enum or message instance. For enums, it provides the ability to retrieve |
| // the enum value number for any concrete enum type. For messages, it provides |
| // the ability to access or manipulate fields of the message. |
| // |
| // To convert a proto.Message to a protoreflect.Message, use the |
| // former's ProtoReflect method. Since the ProtoReflect method is new to the |
| // v2 message interface, it may not be present on older message implementations. |
| // The "github.com/golang/protobuf/proto".MessageReflect function can be used |
| // to obtain a reflective view on older messages. |
| // |
| // |
| // Relationships |
| // |
| // The following diagrams demonstrate the relationships between |
| // various types declared in this package. |
| // |
| // |
| // ┌───────────────────────────────────┐ |
| // V │ |
| // ┌────────────── New(n) ─────────────┐ │ |
| // │ │ │ |
| // │ ┌──── Descriptor() ──┐ │ ┌── Number() ──┐ │ |
| // │ │ V V │ V │ |
| // ╔════════════╗ ╔════════════════╗ ╔════════╗ ╔════════════╗ |
| // ║ EnumType ║ ║ EnumDescriptor ║ ║ Enum ║ ║ EnumNumber ║ |
| // ╚════════════╝ ╚════════════════╝ ╚════════╝ ╚════════════╝ |
| // Λ Λ │ │ |
| // │ └─── Descriptor() ──┘ │ |
| // │ │ |
| // └────────────────── Type() ───────┘ |
| // |
| // • An EnumType describes a concrete Go enum type. |
| // It has an EnumDescriptor and can construct an Enum instance. |
| // |
| // • An EnumDescriptor describes an abstract protobuf enum type. |
| // |
| // • An Enum is a concrete enum instance. Generated enums implement Enum. |
| // |
| // |
| // ┌──────────────── New() ─────────────────┐ |
| // │ │ |
| // │ ┌─── Descriptor() ─────┐ │ ┌── Interface() ───┐ |
| // │ │ V V │ V |
| // ╔═════════════╗ ╔═══════════════════╗ ╔═════════╗ ╔══════════════╗ |
| // ║ MessageType ║ ║ MessageDescriptor ║ ║ Message ║ ║ ProtoMessage ║ |
| // ╚═════════════╝ ╚═══════════════════╝ ╚═════════╝ ╚══════════════╝ |
| // Λ Λ │ │ Λ │ |
| // │ └──── Descriptor() ────┘ │ └─ ProtoReflect() ─┘ |
| // │ │ |
| // └─────────────────── Type() ─────────┘ |
| // |
| // • A MessageType describes a concrete Go message type. |
| // It has a MessageDescriptor and can construct a Message instance. |
| // |
| // • A MessageDescriptor describes an abstract protobuf message type. |
| // |
| // • A Message is a concrete message instance. Generated messages implement |
| // ProtoMessage, which can convert to/from a Message. |
| // |
| // |
| // ┌── TypeDescriptor() ──┐ ┌───── Descriptor() ─────┐ |
| // │ V │ V |
| // ╔═══════════════╗ ╔═════════════════════════╗ ╔═════════════════════╗ |
| // ║ ExtensionType ║ ║ ExtensionTypeDescriptor ║ ║ ExtensionDescriptor ║ |
| // ╚═══════════════╝ ╚═════════════════════════╝ ╚═════════════════════╝ |
| // Λ │ │ Λ │ Λ |
| // └─────── Type() ───────┘ │ └─── may implement ────┘ │ |
| // │ │ |
| // └────── implements ────────┘ |
| // |
| // • An ExtensionType describes a concrete Go implementation of an extension. |
| // It has an ExtensionTypeDescriptor and can convert to/from |
| // abstract Values and Go values. |
| // |
| // • An ExtensionTypeDescriptor is an ExtensionDescriptor |
| // which also has an ExtensionType. |
| // |
| // • An ExtensionDescriptor describes an abstract protobuf extension field and |
| // may not always be an ExtensionTypeDescriptor. |
| package protoreflect |
| |
| import ( |
| "fmt" |
| "strings" |
| |
| "google.golang.org/protobuf/encoding/protowire" |
| "google.golang.org/protobuf/internal/pragma" |
| ) |
| |
| type doNotImplement pragma.DoNotImplement |
| |
| // ProtoMessage is the top-level interface that all proto messages implement. |
| // This is declared in the protoreflect package to avoid a cyclic dependency; |
| // use the proto.Message type instead, which aliases this type. |
| type ProtoMessage interface{ ProtoReflect() Message } |
| |
| // Syntax is the language version of the proto file. |
| type Syntax syntax |
| |
| type syntax int8 // keep exact type opaque as the int type may change |
| |
| const ( |
| Proto2 Syntax = 2 |
| Proto3 Syntax = 3 |
| ) |
| |
| // IsValid reports whether the syntax is valid. |
| func (s Syntax) IsValid() bool { |
| switch s { |
| case Proto2, Proto3: |
| return true |
| default: |
| return false |
| } |
| } |
| |
| // String returns s as a proto source identifier (e.g., "proto2"). |
| func (s Syntax) String() string { |
| switch s { |
| case Proto2: |
| return "proto2" |
| case Proto3: |
| return "proto3" |
| default: |
| return fmt.Sprintf("<unknown:%d>", s) |
| } |
| } |
| |
| // GoString returns s as a Go source identifier (e.g., "Proto2"). |
| func (s Syntax) GoString() string { |
| switch s { |
| case Proto2: |
| return "Proto2" |
| case Proto3: |
| return "Proto3" |
| default: |
| return fmt.Sprintf("Syntax(%d)", s) |
| } |
| } |
| |
| // Cardinality determines whether a field is optional, required, or repeated. |
| type Cardinality cardinality |
| |
| type cardinality int8 // keep exact type opaque as the int type may change |
| |
| // Constants as defined by the google.protobuf.Cardinality enumeration. |
| const ( |
| Optional Cardinality = 1 // appears zero or one times |
| Required Cardinality = 2 // appears exactly one time; invalid with Proto3 |
| Repeated Cardinality = 3 // appears zero or more times |
| ) |
| |
| // IsValid reports whether the cardinality is valid. |
| func (c Cardinality) IsValid() bool { |
| switch c { |
| case Optional, Required, Repeated: |
| return true |
| default: |
| return false |
| } |
| } |
| |
| // String returns c as a proto source identifier (e.g., "optional"). |
| func (c Cardinality) String() string { |
| switch c { |
| case Optional: |
| return "optional" |
| case Required: |
| return "required" |
| case Repeated: |
| return "repeated" |
| default: |
| return fmt.Sprintf("<unknown:%d>", c) |
| } |
| } |
| |
| // GoString returns c as a Go source identifier (e.g., "Optional"). |
| func (c Cardinality) GoString() string { |
| switch c { |
| case Optional: |
| return "Optional" |
| case Required: |
| return "Required" |
| case Repeated: |
| return "Repeated" |
| default: |
| return fmt.Sprintf("Cardinality(%d)", c) |
| } |
| } |
| |
| // Kind indicates the basic proto kind of a field. |
| type Kind kind |
| |
| type kind int8 // keep exact type opaque as the int type may change |
| |
| // Constants as defined by the google.protobuf.Field.Kind enumeration. |
| const ( |
| BoolKind Kind = 8 |
| EnumKind Kind = 14 |
| Int32Kind Kind = 5 |
| Sint32Kind Kind = 17 |
| Uint32Kind Kind = 13 |
| Int64Kind Kind = 3 |
| Sint64Kind Kind = 18 |
| Uint64Kind Kind = 4 |
| Sfixed32Kind Kind = 15 |
| Fixed32Kind Kind = 7 |
| FloatKind Kind = 2 |
| Sfixed64Kind Kind = 16 |
| Fixed64Kind Kind = 6 |
| DoubleKind Kind = 1 |
| StringKind Kind = 9 |
| BytesKind Kind = 12 |
| MessageKind Kind = 11 |
| GroupKind Kind = 10 |
| ) |
| |
| // IsValid reports whether the kind is valid. |
| func (k Kind) IsValid() bool { |
| switch k { |
| case BoolKind, EnumKind, |
| Int32Kind, Sint32Kind, Uint32Kind, |
| Int64Kind, Sint64Kind, Uint64Kind, |
| Sfixed32Kind, Fixed32Kind, FloatKind, |
| Sfixed64Kind, Fixed64Kind, DoubleKind, |
| StringKind, BytesKind, MessageKind, GroupKind: |
| return true |
| default: |
| return false |
| } |
| } |
| |
| // String returns k as a proto source identifier (e.g., "bool"). |
| func (k Kind) String() string { |
| switch k { |
| case BoolKind: |
| return "bool" |
| case EnumKind: |
| return "enum" |
| case Int32Kind: |
| return "int32" |
| case Sint32Kind: |
| return "sint32" |
| case Uint32Kind: |
| return "uint32" |
| case Int64Kind: |
| return "int64" |
| case Sint64Kind: |
| return "sint64" |
| case Uint64Kind: |
| return "uint64" |
| case Sfixed32Kind: |
| return "sfixed32" |
| case Fixed32Kind: |
| return "fixed32" |
| case FloatKind: |
| return "float" |
| case Sfixed64Kind: |
| return "sfixed64" |
| case Fixed64Kind: |
| return "fixed64" |
| case DoubleKind: |
| return "double" |
| case StringKind: |
| return "string" |
| case BytesKind: |
| return "bytes" |
| case MessageKind: |
| return "message" |
| case GroupKind: |
| return "group" |
| default: |
| return fmt.Sprintf("<unknown:%d>", k) |
| } |
| } |
| |
| // GoString returns k as a Go source identifier (e.g., "BoolKind"). |
| func (k Kind) GoString() string { |
| switch k { |
| case BoolKind: |
| return "BoolKind" |
| case EnumKind: |
| return "EnumKind" |
| case Int32Kind: |
| return "Int32Kind" |
| case Sint32Kind: |
| return "Sint32Kind" |
| case Uint32Kind: |
| return "Uint32Kind" |
| case Int64Kind: |
| return "Int64Kind" |
| case Sint64Kind: |
| return "Sint64Kind" |
| case Uint64Kind: |
| return "Uint64Kind" |
| case Sfixed32Kind: |
| return "Sfixed32Kind" |
| case Fixed32Kind: |
| return "Fixed32Kind" |
| case FloatKind: |
| return "FloatKind" |
| case Sfixed64Kind: |
| return "Sfixed64Kind" |
| case Fixed64Kind: |
| return "Fixed64Kind" |
| case DoubleKind: |
| return "DoubleKind" |
| case StringKind: |
| return "StringKind" |
| case BytesKind: |
| return "BytesKind" |
| case MessageKind: |
| return "MessageKind" |
| case GroupKind: |
| return "GroupKind" |
| default: |
| return fmt.Sprintf("Kind(%d)", k) |
| } |
| } |
| |
| // FieldNumber is the field number in a message. |
| type FieldNumber = protowire.Number |
| |
| // FieldNumbers represent a list of field numbers. |
| type FieldNumbers interface { |
| // Len reports the number of fields in the list. |
| Len() int |
| // Get returns the ith field number. It panics if out of bounds. |
| Get(i int) FieldNumber |
| // Has reports whether n is within the list of fields. |
| Has(n FieldNumber) bool |
| |
| doNotImplement |
| } |
| |
| // FieldRanges represent a list of field number ranges. |
| type FieldRanges interface { |
| // Len reports the number of ranges in the list. |
| Len() int |
| // Get returns the ith range. It panics if out of bounds. |
| Get(i int) [2]FieldNumber // start inclusive; end exclusive |
| // Has reports whether n is within any of the ranges. |
| Has(n FieldNumber) bool |
| |
| doNotImplement |
| } |
| |
| // EnumNumber is the numeric value for an enum. |
| type EnumNumber int32 |
| |
| // EnumRanges represent a list of enum number ranges. |
| type EnumRanges interface { |
| // Len reports the number of ranges in the list. |
| Len() int |
| // Get returns the ith range. It panics if out of bounds. |
| Get(i int) [2]EnumNumber // start inclusive; end inclusive |
| // Has reports whether n is within any of the ranges. |
| Has(n EnumNumber) bool |
| |
| doNotImplement |
| } |
| |
| // Name is the short name for a proto declaration. This is not the name |
| // as used in Go source code, which might not be identical to the proto name. |
| type Name string // e.g., "Kind" |
| |
| // IsValid reports whether s is a syntactically valid name. |
| // An empty name is invalid. |
| func (s Name) IsValid() bool { |
| return consumeIdent(string(s)) == len(s) |
| } |
| |
| // Names represent a list of names. |
| type Names interface { |
| // Len reports the number of names in the list. |
| Len() int |
| // Get returns the ith name. It panics if out of bounds. |
| Get(i int) Name |
| // Has reports whether s matches any names in the list. |
| Has(s Name) bool |
| |
| doNotImplement |
| } |
| |
| // FullName is a qualified name that uniquely identifies a proto declaration. |
| // A qualified name is the concatenation of the proto package along with the |
| // fully-declared name (i.e., name of parent preceding the name of the child), |
| // with a '.' delimiter placed between each Name. |
| // |
| // This should not have any leading or trailing dots. |
| type FullName string // e.g., "google.protobuf.Field.Kind" |
| |
| // IsValid reports whether s is a syntactically valid full name. |
| // An empty full name is invalid. |
| func (s FullName) IsValid() bool { |
| i := consumeIdent(string(s)) |
| if i < 0 { |
| return false |
| } |
| for len(s) > i { |
| if s[i] != '.' { |
| return false |
| } |
| i++ |
| n := consumeIdent(string(s[i:])) |
| if n < 0 { |
| return false |
| } |
| i += n |
| } |
| return true |
| } |
| |
| func consumeIdent(s string) (i int) { |
| if len(s) == 0 || !isLetter(s[i]) { |
| return -1 |
| } |
| i++ |
| for len(s) > i && isLetterDigit(s[i]) { |
| i++ |
| } |
| return i |
| } |
| func isLetter(c byte) bool { |
| return c == '_' || ('a' <= c && c <= 'z') || ('A' <= c && c <= 'Z') |
| } |
| func isLetterDigit(c byte) bool { |
| return isLetter(c) || ('0' <= c && c <= '9') |
| } |
| |
| // Name returns the short name, which is the last identifier segment. |
| // A single segment FullName is the Name itself. |
| func (n FullName) Name() Name { |
| if i := strings.LastIndexByte(string(n), '.'); i >= 0 { |
| return Name(n[i+1:]) |
| } |
| return Name(n) |
| } |
| |
| // Parent returns the full name with the trailing identifier removed. |
| // A single segment FullName has no parent. |
| func (n FullName) Parent() FullName { |
| if i := strings.LastIndexByte(string(n), '.'); i >= 0 { |
| return n[:i] |
| } |
| return "" |
| } |
| |
| // Append returns the qualified name appended with the provided short name. |
| // |
| // Invariant: n == n.Parent().Append(n.Name()) // assuming n is valid |
| func (n FullName) Append(s Name) FullName { |
| if n == "" { |
| return FullName(s) |
| } |
| return n + "." + FullName(s) |
| } |