blob: 900b9d287475a65d364b10f23119d5460a14908d [file] [log] [blame]
// Copyright 2019 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 dynamicpb creates protocol buffer messages using runtime type information.
package dynamicpb
import (
"math"
"google.golang.org/protobuf/internal/errors"
pref "google.golang.org/protobuf/reflect/protoreflect"
"google.golang.org/protobuf/runtime/protoiface"
"google.golang.org/protobuf/runtime/protoimpl"
)
// enum is a dynamic protoreflect.Enum.
type enum struct {
num pref.EnumNumber
typ pref.EnumType
}
func (e enum) Descriptor() pref.EnumDescriptor { return e.typ.Descriptor() }
func (e enum) Type() pref.EnumType { return e.typ }
func (e enum) Number() pref.EnumNumber { return e.num }
// enumType is a dynamic protoreflect.EnumType.
type enumType struct {
desc pref.EnumDescriptor
}
// NewEnumType creates a new EnumType with the provided descriptor.
//
// EnumTypes created by this package are equal if their descriptors are equal.
// That is, if ed1 == ed2, then NewEnumType(ed1) == NewEnumType(ed2).
//
// Enum values created by the EnumType are equal if their numbers are equal.
func NewEnumType(desc pref.EnumDescriptor) pref.EnumType {
return enumType{desc}
}
func (et enumType) New(n pref.EnumNumber) pref.Enum { return enum{n, et} }
func (et enumType) Descriptor() pref.EnumDescriptor { return et.desc }
// extensionType is a dynamic protoreflect.ExtensionType.
type extensionType struct {
desc extensionTypeDescriptor
}
// A Message is a dynamically constructed protocol buffer message.
//
// Message implements the proto.Message interface, and may be used with all
// standard proto package functions such as Marshal, Unmarshal, and so forth.
//
// Message also implements the protoreflect.Message interface. See the protoreflect
// package documentation for that interface for how to get and set fields and
// otherwise interact with the contents of a Message.
//
// Reflection API functions which construct messages, such as NewField,
// return new dynamic messages of the appropriate type. Functions which take
// messages, such as Set for a message-value field, will accept any message
// with a compatible type.
//
// Operations which modify a Message are not safe for concurrent use.
type Message struct {
typ messageType
known map[pref.FieldNumber]pref.Value
ext map[pref.FieldNumber]pref.FieldDescriptor
unknown pref.RawFields
}
var (
_ pref.Message = (*Message)(nil)
_ pref.ProtoMessage = (*Message)(nil)
_ protoiface.MessageV1 = (*Message)(nil)
)
// NewMessage creates a new message with the provided descriptor.
func NewMessage(desc pref.MessageDescriptor) *Message {
return &Message{
typ: messageType{desc},
known: make(map[pref.FieldNumber]pref.Value),
ext: make(map[pref.FieldNumber]pref.FieldDescriptor),
}
}
// ProtoMessage implements the legacy message interface.
func (m *Message) ProtoMessage() {}
// ProtoReflect implements the protoreflect.ProtoMessage interface.
func (m *Message) ProtoReflect() pref.Message {
return m
}
// String returns a string representation of a message.
func (m *Message) String() string {
return protoimpl.X.MessageStringOf(m)
}
// Reset clears the message to be empty, but preserves the dynamic message type.
func (m *Message) Reset() {
m.known = make(map[pref.FieldNumber]pref.Value)
m.ext = make(map[pref.FieldNumber]pref.FieldDescriptor)
m.unknown = nil
}
// Descriptor returns the message descriptor.
func (m *Message) Descriptor() pref.MessageDescriptor {
return m.typ.desc
}
// Type returns the message type.
func (m *Message) Type() pref.MessageType {
return m.typ
}
// New returns a newly allocated empty message with the same descriptor.
// See protoreflect.Message for details.
func (m *Message) New() pref.Message {
return m.Type().New()
}
// Interface returns the message.
// See protoreflect.Message for details.
func (m *Message) Interface() pref.ProtoMessage {
return m
}
// ProtoMethods is an internal detail of the protoreflect.Message interface.
// Users should never call this directly.
func (m *Message) ProtoMethods() *protoiface.Methods {
return nil
}
// Range visits every populated field in undefined order.
// See protoreflect.Message for details.
func (m *Message) Range(f func(pref.FieldDescriptor, pref.Value) bool) {
for num, v := range m.known {
fd := m.ext[num]
if fd == nil {
fd = m.Descriptor().Fields().ByNumber(num)
}
if !isSet(fd, v) {
continue
}
if !f(fd, v) {
return
}
}
}
// Has reports whether a field is populated.
// See protoreflect.Message for details.
func (m *Message) Has(fd pref.FieldDescriptor) bool {
m.checkField(fd)
if fd.IsExtension() && m.ext[fd.Number()] != fd {
return false
}
v, ok := m.known[fd.Number()]
if !ok {
return false
}
return isSet(fd, v)
}
// Clear clears a field.
// See protoreflect.Message for details.
func (m *Message) Clear(fd pref.FieldDescriptor) {
m.checkField(fd)
num := fd.Number()
delete(m.known, num)
delete(m.ext, num)
}
// Get returns the value of a field.
// See protoreflect.Message for details.
func (m *Message) Get(fd pref.FieldDescriptor) pref.Value {
m.checkField(fd)
num := fd.Number()
if fd.IsExtension() {
if fd != m.ext[num] {
return fd.(pref.ExtensionTypeDescriptor).Type().Zero()
}
return m.known[num]
}
if v, ok := m.known[num]; ok {
switch {
case fd.IsMap():
if v.Map().Len() > 0 {
return v
}
case fd.IsList():
if v.List().Len() > 0 {
return v
}
default:
return v
}
}
switch {
case fd.IsMap():
return pref.ValueOfMap(&dynamicMap{desc: fd})
case fd.IsList():
return pref.ValueOfList(emptyList{desc: fd})
case fd.Message() != nil:
return pref.ValueOfMessage(&Message{typ: messageType{fd.Message()}})
case fd.Kind() == pref.BytesKind:
return pref.ValueOfBytes(append([]byte(nil), fd.Default().Bytes()...))
default:
return fd.Default()
}
}
// Mutable returns a mutable reference to a repeated, map, or message field.
// See protoreflect.Message for details.
func (m *Message) Mutable(fd pref.FieldDescriptor) pref.Value {
m.checkField(fd)
if !fd.IsMap() && !fd.IsList() && fd.Message() == nil {
panic(errors.New("%v: getting mutable reference to non-composite type", fd.FullName()))
}
if m.known == nil {
panic(errors.New("%v: modification of read-only message", fd.FullName()))
}
num := fd.Number()
if fd.IsExtension() {
if fd != m.ext[num] {
m.ext[num] = fd
m.known[num] = fd.(pref.ExtensionTypeDescriptor).Type().New()
}
return m.known[num]
}
if v, ok := m.known[num]; ok {
return v
}
m.clearOtherOneofFields(fd)
m.known[num] = m.NewField(fd)
if fd.IsExtension() {
m.ext[num] = fd
}
return m.known[num]
}
// Set stores a value in a field.
// See protoreflect.Message for details.
func (m *Message) Set(fd pref.FieldDescriptor, v pref.Value) {
m.checkField(fd)
if m.known == nil {
panic(errors.New("%v: modification of read-only message", fd.FullName()))
}
if fd.IsExtension() {
isValid := true
switch {
case !fd.(pref.ExtensionTypeDescriptor).Type().IsValidValue(v):
isValid = false
case fd.IsList():
isValid = v.List().IsValid()
case fd.IsMap():
isValid = v.Map().IsValid()
case fd.Message() != nil:
isValid = v.Message().IsValid()
}
if !isValid {
panic(errors.New("%v: assigning invalid type %T", fd.FullName(), v.Interface()))
}
m.ext[fd.Number()] = fd
} else {
typecheck(fd, v)
}
m.clearOtherOneofFields(fd)
m.known[fd.Number()] = v
}
func (m *Message) clearOtherOneofFields(fd pref.FieldDescriptor) {
od := fd.ContainingOneof()
if od == nil {
return
}
num := fd.Number()
for i := 0; i < od.Fields().Len(); i++ {
if n := od.Fields().Get(i).Number(); n != num {
delete(m.known, n)
}
}
}
// NewField returns a new value for assignable to the field of a given descriptor.
// See protoreflect.Message for details.
func (m *Message) NewField(fd pref.FieldDescriptor) pref.Value {
m.checkField(fd)
switch {
case fd.IsExtension():
return fd.(pref.ExtensionTypeDescriptor).Type().New()
case fd.IsMap():
return pref.ValueOfMap(&dynamicMap{
desc: fd,
mapv: make(map[interface{}]pref.Value),
})
case fd.IsList():
return pref.ValueOfList(&dynamicList{desc: fd})
case fd.Message() != nil:
return pref.ValueOfMessage(NewMessage(fd.Message()).ProtoReflect())
default:
return fd.Default()
}
}
// WhichOneof reports which field in a oneof is populated, returning nil if none are populated.
// See protoreflect.Message for details.
func (m *Message) WhichOneof(od pref.OneofDescriptor) pref.FieldDescriptor {
for i := 0; i < od.Fields().Len(); i++ {
fd := od.Fields().Get(i)
if m.Has(fd) {
return fd
}
}
return nil
}
// GetUnknown returns the raw unknown fields.
// See protoreflect.Message for details.
func (m *Message) GetUnknown() pref.RawFields {
return m.unknown
}
// SetUnknown sets the raw unknown fields.
// See protoreflect.Message for details.
func (m *Message) SetUnknown(r pref.RawFields) {
if m.known == nil {
panic(errors.New("%v: modification of read-only message", m.typ.desc.FullName()))
}
m.unknown = r
}
// IsValid reports whether the message is valid.
// See protoreflect.Message for details.
func (m *Message) IsValid() bool {
return m.known != nil
}
func (m *Message) checkField(fd pref.FieldDescriptor) {
if fd.IsExtension() && fd.ContainingMessage().FullName() == m.Descriptor().FullName() {
if _, ok := fd.(pref.ExtensionTypeDescriptor); !ok {
panic(errors.New("%v: extension field descriptor does not implement ExtensionTypeDescriptor", fd.FullName()))
}
return
}
if fd.Parent() == m.Descriptor() {
return
}
fields := m.Descriptor().Fields()
index := fd.Index()
if index >= fields.Len() || fields.Get(index) != fd {
panic(errors.New("%v: field descriptor does not belong to this message", fd.FullName()))
}
}
type messageType struct {
desc pref.MessageDescriptor
}
// NewMessageType creates a new MessageType with the provided descriptor.
//
// MessageTypes created by this package are equal if their descriptors are equal.
// That is, if md1 == md2, then NewMessageType(md1) == NewMessageType(md2).
func NewMessageType(desc pref.MessageDescriptor) pref.MessageType {
return messageType{desc}
}
func (mt messageType) New() pref.Message { return NewMessage(mt.desc) }
func (mt messageType) Zero() pref.Message { return &Message{typ: messageType{mt.desc}} }
func (mt messageType) Descriptor() pref.MessageDescriptor { return mt.desc }
func (mt messageType) Enum(i int) pref.EnumType {
if ed := mt.desc.Fields().Get(i).Enum(); ed != nil {
return NewEnumType(ed)
}
return nil
}
func (mt messageType) Message(i int) pref.MessageType {
if md := mt.desc.Fields().Get(i).Message(); md != nil {
return NewMessageType(md)
}
return nil
}
type emptyList struct {
desc pref.FieldDescriptor
}
func (x emptyList) Len() int { return 0 }
func (x emptyList) Get(n int) pref.Value { panic(errors.New("out of range")) }
func (x emptyList) Set(n int, v pref.Value) { panic(errors.New("modification of immutable list")) }
func (x emptyList) Append(v pref.Value) { panic(errors.New("modification of immutable list")) }
func (x emptyList) AppendMutable() pref.Value { panic(errors.New("modification of immutable list")) }
func (x emptyList) Truncate(n int) { panic(errors.New("modification of immutable list")) }
func (x emptyList) NewElement() pref.Value { return newListEntry(x.desc) }
func (x emptyList) IsValid() bool { return false }
type dynamicList struct {
desc pref.FieldDescriptor
list []pref.Value
}
func (x *dynamicList) Len() int {
return len(x.list)
}
func (x *dynamicList) Get(n int) pref.Value {
return x.list[n]
}
func (x *dynamicList) Set(n int, v pref.Value) {
typecheckSingular(x.desc, v)
x.list[n] = v
}
func (x *dynamicList) Append(v pref.Value) {
typecheckSingular(x.desc, v)
x.list = append(x.list, v)
}
func (x *dynamicList) AppendMutable() pref.Value {
if x.desc.Message() == nil {
panic(errors.New("%v: invalid AppendMutable on list with non-message type", x.desc.FullName()))
}
v := x.NewElement()
x.Append(v)
return v
}
func (x *dynamicList) Truncate(n int) {
// Zero truncated elements to avoid keeping data live.
for i := n; i < len(x.list); i++ {
x.list[i] = pref.Value{}
}
x.list = x.list[:n]
}
func (x *dynamicList) NewElement() pref.Value {
return newListEntry(x.desc)
}
func (x *dynamicList) IsValid() bool {
return true
}
type dynamicMap struct {
desc pref.FieldDescriptor
mapv map[interface{}]pref.Value
}
func (x *dynamicMap) Get(k pref.MapKey) pref.Value { return x.mapv[k.Interface()] }
func (x *dynamicMap) Set(k pref.MapKey, v pref.Value) {
typecheckSingular(x.desc.MapKey(), k.Value())
typecheckSingular(x.desc.MapValue(), v)
x.mapv[k.Interface()] = v
}
func (x *dynamicMap) Has(k pref.MapKey) bool { return x.Get(k).IsValid() }
func (x *dynamicMap) Clear(k pref.MapKey) { delete(x.mapv, k.Interface()) }
func (x *dynamicMap) Mutable(k pref.MapKey) pref.Value {
if x.desc.MapValue().Message() == nil {
panic(errors.New("%v: invalid Mutable on map with non-message value type", x.desc.FullName()))
}
v := x.Get(k)
if !v.IsValid() {
v = x.NewValue()
x.Set(k, v)
}
return v
}
func (x *dynamicMap) Len() int { return len(x.mapv) }
func (x *dynamicMap) NewValue() pref.Value {
if md := x.desc.MapValue().Message(); md != nil {
return pref.ValueOfMessage(NewMessage(md).ProtoReflect())
}
return x.desc.MapValue().Default()
}
func (x *dynamicMap) IsValid() bool {
return x.mapv != nil
}
func (x *dynamicMap) Range(f func(pref.MapKey, pref.Value) bool) {
for k, v := range x.mapv {
if !f(pref.ValueOf(k).MapKey(), v) {
return
}
}
}
func isSet(fd pref.FieldDescriptor, v pref.Value) bool {
switch {
case fd.IsMap():
return v.Map().Len() > 0
case fd.IsList():
return v.List().Len() > 0
case fd.ContainingOneof() != nil:
return true
case fd.Syntax() == pref.Proto3 && !fd.IsExtension():
switch fd.Kind() {
case pref.BoolKind:
return v.Bool()
case pref.EnumKind:
return v.Enum() != 0
case pref.Int32Kind, pref.Sint32Kind, pref.Int64Kind, pref.Sint64Kind, pref.Sfixed32Kind, pref.Sfixed64Kind:
return v.Int() != 0
case pref.Uint32Kind, pref.Uint64Kind, pref.Fixed32Kind, pref.Fixed64Kind:
return v.Uint() != 0
case pref.FloatKind, pref.DoubleKind:
return v.Float() != 0 || math.Signbit(v.Float())
case pref.StringKind:
return v.String() != ""
case pref.BytesKind:
return len(v.Bytes()) > 0
}
}
return true
}
func typecheck(fd pref.FieldDescriptor, v pref.Value) {
if err := typeIsValid(fd, v); err != nil {
panic(err)
}
}
func typeIsValid(fd pref.FieldDescriptor, v pref.Value) error {
switch {
case !v.IsValid():
return errors.New("%v: assigning invalid value", fd.FullName())
case fd.IsMap():
if mapv, ok := v.Interface().(*dynamicMap); !ok || mapv.desc != fd || !mapv.IsValid() {
return errors.New("%v: assigning invalid type %T", fd.FullName(), v.Interface())
}
return nil
case fd.IsList():
switch list := v.Interface().(type) {
case *dynamicList:
if list.desc == fd && list.IsValid() {
return nil
}
case emptyList:
if list.desc == fd && list.IsValid() {
return nil
}
}
return errors.New("%v: assigning invalid type %T", fd.FullName(), v.Interface())
default:
return singularTypeIsValid(fd, v)
}
}
func typecheckSingular(fd pref.FieldDescriptor, v pref.Value) {
if err := singularTypeIsValid(fd, v); err != nil {
panic(err)
}
}
func singularTypeIsValid(fd pref.FieldDescriptor, v pref.Value) error {
vi := v.Interface()
var ok bool
switch fd.Kind() {
case pref.BoolKind:
_, ok = vi.(bool)
case pref.EnumKind:
// We could check against the valid set of enum values, but do not.
_, ok = vi.(pref.EnumNumber)
case pref.Int32Kind, pref.Sint32Kind, pref.Sfixed32Kind:
_, ok = vi.(int32)
case pref.Uint32Kind, pref.Fixed32Kind:
_, ok = vi.(uint32)
case pref.Int64Kind, pref.Sint64Kind, pref.Sfixed64Kind:
_, ok = vi.(int64)
case pref.Uint64Kind, pref.Fixed64Kind:
_, ok = vi.(uint64)
case pref.FloatKind:
_, ok = vi.(float32)
case pref.DoubleKind:
_, ok = vi.(float64)
case pref.StringKind:
_, ok = vi.(string)
case pref.BytesKind:
_, ok = vi.([]byte)
case pref.MessageKind, pref.GroupKind:
var m pref.Message
m, ok = vi.(pref.Message)
if ok && m.Descriptor().FullName() != fd.Message().FullName() {
return errors.New("%v: assigning invalid message type %v", fd.FullName(), m.Descriptor().FullName())
}
if dm, ok := vi.(*Message); ok && dm.known == nil {
return errors.New("%v: assigning invalid zero-value message", fd.FullName())
}
}
if !ok {
return errors.New("%v: assigning invalid type %T", fd.FullName(), v.Interface())
}
return nil
}
func newListEntry(fd pref.FieldDescriptor) pref.Value {
switch fd.Kind() {
case pref.BoolKind:
return pref.ValueOfBool(false)
case pref.EnumKind:
return pref.ValueOfEnum(fd.Enum().Values().Get(0).Number())
case pref.Int32Kind, pref.Sint32Kind, pref.Sfixed32Kind:
return pref.ValueOfInt32(0)
case pref.Uint32Kind, pref.Fixed32Kind:
return pref.ValueOfUint32(0)
case pref.Int64Kind, pref.Sint64Kind, pref.Sfixed64Kind:
return pref.ValueOfInt64(0)
case pref.Uint64Kind, pref.Fixed64Kind:
return pref.ValueOfUint64(0)
case pref.FloatKind:
return pref.ValueOfFloat32(0)
case pref.DoubleKind:
return pref.ValueOfFloat64(0)
case pref.StringKind:
return pref.ValueOfString("")
case pref.BytesKind:
return pref.ValueOfBytes(nil)
case pref.MessageKind, pref.GroupKind:
return pref.ValueOfMessage(NewMessage(fd.Message()).ProtoReflect())
}
panic(errors.New("%v: unknown kind %v", fd.FullName(), fd.Kind()))
}
// NewExtensionType creates a new ExtensionType with the provided descriptor.
//
// Dynamic ExtensionTypes with the same descriptor compare as equal. That is,
// if xd1 == xd2, then NewExtensionType(xd1) == NewExtensionType(xd2).
//
// The InterfaceOf and ValueOf methods of the extension type are defined as:
//
// func (xt extensionType) ValueOf(iv interface{}) protoreflect.Value {
// return protoreflect.ValueOf(iv)
// }
//
// func (xt extensionType) InterfaceOf(v protoreflect.Value) interface{} {
// return v.Interface()
// }
//
// The Go type used by the proto.GetExtension and proto.SetExtension functions
// is determined by these methods, and is therefore equivalent to the Go type
// used to represent a protoreflect.Value. See the protoreflect.Value
// documentation for more details.
func NewExtensionType(desc pref.ExtensionDescriptor) pref.ExtensionType {
if xt, ok := desc.(pref.ExtensionTypeDescriptor); ok {
desc = xt.Descriptor()
}
return extensionType{extensionTypeDescriptor{desc}}
}
func (xt extensionType) New() pref.Value {
switch {
case xt.desc.IsMap():
return pref.ValueOfMap(&dynamicMap{
desc: xt.desc,
mapv: make(map[interface{}]pref.Value),
})
case xt.desc.IsList():
return pref.ValueOfList(&dynamicList{desc: xt.desc})
case xt.desc.Message() != nil:
return pref.ValueOfMessage(NewMessage(xt.desc.Message()))
default:
return xt.desc.Default()
}
}
func (xt extensionType) Zero() pref.Value {
switch {
case xt.desc.IsMap():
return pref.ValueOfMap(&dynamicMap{desc: xt.desc})
case xt.desc.Cardinality() == pref.Repeated:
return pref.ValueOfList(emptyList{desc: xt.desc})
case xt.desc.Message() != nil:
return pref.ValueOfMessage(&Message{typ: messageType{xt.desc.Message()}})
default:
return xt.desc.Default()
}
}
func (xt extensionType) TypeDescriptor() pref.ExtensionTypeDescriptor {
return xt.desc
}
func (xt extensionType) ValueOf(iv interface{}) pref.Value {
v := pref.ValueOf(iv)
typecheck(xt.desc, v)
return v
}
func (xt extensionType) InterfaceOf(v pref.Value) interface{} {
typecheck(xt.desc, v)
return v.Interface()
}
func (xt extensionType) IsValidInterface(iv interface{}) bool {
return typeIsValid(xt.desc, pref.ValueOf(iv)) == nil
}
func (xt extensionType) IsValidValue(v pref.Value) bool {
return typeIsValid(xt.desc, v) == nil
}
type extensionTypeDescriptor struct {
pref.ExtensionDescriptor
}
func (xt extensionTypeDescriptor) Type() pref.ExtensionType {
return extensionType{xt}
}
func (xt extensionTypeDescriptor) Descriptor() pref.ExtensionDescriptor {
return xt.ExtensionDescriptor
}