reflect/protoreflect: add alternative message reflection API
Added API:
Message.Len
Message.Range
Message.Has
Message.Clear
Message.Get
Message.Set
Message.Mutable
Message.NewMessage
Message.WhichOneof
Message.GetUnknown
Message.SetUnknown
Deprecated API (to be removed in subsequent CL):
Message.KnownFields
Message.UnknownFields
The primary difference with the new API is that the top-level
Message methods are keyed by FieldDescriptor rather than FieldNumber
with the following semantics:
* For known fields, the FieldDescriptor must exactly match the
field descriptor known by the message.
* For extension fields, the FieldDescriptor must implement ExtensionType,
where ContainingMessage.FullName matches the message name, and
the field number is within the message's extension range.
When setting an extension field, it automatically stores
the extension type information.
* Extension fields are always considered nullable,
implying that repeated extension fields are nullable.
That is, you can distinguish between a unpopulated list and an empty list.
* Message.Get always returns a valid Value even if unpopulated.
The behavior is already well-defined for scalars, but for unpopulated
composite types, it now returns an empty read-only version of it.
Change-Id: Ia120630b4db221aeaaf743d0f64160e1a61a0f61
Reviewed-on: https://go-review.googlesource.com/c/protobuf/+/175458
Reviewed-by: Damien Neil <dneil@google.com>
diff --git a/encoding/prototext/decode.go b/encoding/prototext/decode.go
index 20bdfe6..4444de6 100644
--- a/encoding/prototext/decode.go
+++ b/encoding/prototext/decode.go
@@ -47,12 +47,11 @@
func (o UnmarshalOptions) Unmarshal(b []byte, m proto.Message) error {
var nerr errors.NonFatal
- mr := m.ProtoReflect()
// Clear all fields before populating it.
// TODO: Determine if this needs to be consistent with protojson and binary unmarshal where
// behavior is to merge values into existing message. If decision is to not clear the fields
// ahead, code will need to be updated properly when merging nested messages.
- resetMessage(mr)
+ proto.Reset(m)
// Parse into text.Value of message type.
val, err := text.Unmarshal(b)
@@ -63,7 +62,7 @@
if o.Resolver == nil {
o.Resolver = protoregistry.GlobalTypes
}
- err = o.unmarshalMessage(val.Message(), mr)
+ err = o.unmarshalMessage(val.Message(), m.ProtoReflect())
if !nerr.Merge(err) {
return err
}
@@ -75,41 +74,19 @@
return nerr.E
}
-// resetMessage clears all fields of given protoreflect.Message.
-// TODO: This should go into the proto package.
-func resetMessage(m pref.Message) {
- knownFields := m.KnownFields()
- knownFields.Range(func(num pref.FieldNumber, _ pref.Value) bool {
- knownFields.Clear(num)
- return true
- })
- unknownFields := m.UnknownFields()
- unknownFields.Range(func(num pref.FieldNumber, _ pref.RawFields) bool {
- unknownFields.Set(num, nil)
- return true
- })
- extTypes := knownFields.ExtensionTypes()
- extTypes.Range(func(xt pref.ExtensionType) bool {
- extTypes.Remove(xt)
- return true
- })
-}
-
// unmarshalMessage unmarshals a [][2]text.Value message into the given protoreflect.Message.
func (o UnmarshalOptions) unmarshalMessage(tmsg [][2]text.Value, m pref.Message) error {
var nerr errors.NonFatal
messageDesc := m.Descriptor()
- knownFields := m.KnownFields()
// Handle expanded Any message.
if messageDesc.FullName() == "google.protobuf.Any" && isExpandedAny(tmsg) {
- return o.unmarshalAny(tmsg[0], knownFields)
+ return o.unmarshalAny(tmsg[0], m)
}
fieldDescs := messageDesc.Fields()
reservedNames := messageDesc.ReservedNames()
- xtTypes := knownFields.ExtensionTypes()
var seenNums set.Ints
var seenOneofs set.Ints
@@ -134,23 +111,14 @@
}
// Extensions have to be registered first in the message's
// ExtensionTypes before setting a value to it.
- xtName := pref.FullName(tkey.String())
+ extName := pref.FullName(tkey.String())
// Check first if it is already registered. This is the case for
// repeated fields.
- xt := xtTypes.ByName(xtName)
- if xt == nil {
- var err error
- xt, err = o.findExtension(xtName)
- if err != nil && err != protoregistry.NotFound {
- return errors.New("unable to resolve [%v]: %v", xtName, err)
- }
- if xt != nil {
- xtTypes.Register(xt)
- }
+ xt, err := o.findExtension(extName)
+ if err != nil && err != protoregistry.NotFound {
+ return errors.New("unable to resolve [%v]: %v", extName, err)
}
- if xt != nil {
- fd = xt.Descriptor()
- }
+ fd = xt
}
if fd == nil {
@@ -172,7 +140,7 @@
items = tval.List()
}
- list := knownFields.Get(fd.Number()).List()
+ list := m.Mutable(fd).List()
if err := o.unmarshalList(items, fd, list); !nerr.Merge(err) {
return err
}
@@ -185,7 +153,7 @@
items = tval.List()
}
- mmap := knownFields.Get(fd.Number()).Map()
+ mmap := m.Mutable(fd).Map()
if err := o.unmarshalMap(items, fd, mmap); !nerr.Merge(err) {
return err
}
@@ -204,7 +172,7 @@
if seenNums.Has(num) {
return errors.New("non-repeated field %v is repeated", fd.FullName())
}
- if err := o.unmarshalSingular(tval, fd, knownFields); !nerr.Merge(err) {
+ if err := o.unmarshalSingular(tval, fd, m); !nerr.Merge(err) {
return err
}
seenNums.Set(num)
@@ -230,9 +198,7 @@
}
// unmarshalSingular unmarshals given text.Value into the non-repeated field.
-func (o UnmarshalOptions) unmarshalSingular(input text.Value, fd pref.FieldDescriptor, knownFields pref.KnownFields) error {
- num := fd.Number()
-
+func (o UnmarshalOptions) unmarshalSingular(input text.Value, fd pref.FieldDescriptor, m pref.Message) error {
var nerr errors.NonFatal
var val pref.Value
switch fd.Kind() {
@@ -240,11 +206,11 @@
if input.Type() != text.Message {
return errors.New("%v contains invalid message/group value: %v", fd.FullName(), input)
}
- m := knownFields.NewMessage(num)
- if err := o.unmarshalMessage(input.Message(), m); !nerr.Merge(err) {
+ m2 := m.NewMessage(fd)
+ if err := o.unmarshalMessage(input.Message(), m2); !nerr.Merge(err) {
return err
}
- val = pref.ValueOf(m)
+ val = pref.ValueOf(m2)
default:
var err error
val, err = unmarshalScalar(input, fd)
@@ -252,7 +218,7 @@
return err
}
}
- knownFields.Set(num, val)
+ m.Set(fd, val)
return nerr.E
}
@@ -480,7 +446,7 @@
// unmarshalAny unmarshals an expanded Any textproto. This method assumes that the given
// tfield has key type of text.String and value type of text.Message.
-func (o UnmarshalOptions) unmarshalAny(tfield [2]text.Value, knownFields pref.KnownFields) error {
+func (o UnmarshalOptions) unmarshalAny(tfield [2]text.Value, m pref.Message) error {
var nerr errors.NonFatal
typeURL := tfield[0].String()
@@ -492,8 +458,8 @@
}
// Create new message for the embedded message type and unmarshal the
// value into it.
- m := mt.New()
- if err := o.unmarshalMessage(value, m); !nerr.Merge(err) {
+ m2 := mt.New()
+ if err := o.unmarshalMessage(value, m2); !nerr.Merge(err) {
return err
}
// Serialize the embedded message and assign the resulting bytes to the value field.
@@ -503,13 +469,17 @@
b, err := proto.MarshalOptions{
AllowPartial: o.AllowPartial,
Deterministic: true,
- }.Marshal(m.Interface())
+ }.Marshal(m2.Interface())
if !nerr.Merge(err) {
return err
}
- knownFields.Set(fieldnum.Any_TypeUrl, pref.ValueOf(typeURL))
- knownFields.Set(fieldnum.Any_Value, pref.ValueOf(b))
+ fds := m.Descriptor().Fields()
+ fdType := fds.ByNumber(fieldnum.Any_TypeUrl)
+ fdValue := fds.ByNumber(fieldnum.Any_Value)
+
+ m.Set(fdType, pref.ValueOf(typeURL))
+ m.Set(fdValue, pref.ValueOf(b))
return nerr.E
}