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/encode.go b/encoding/prototext/encode.go
index d86492e..c3a91ca 100644
--- a/encoding/prototext/encode.go
+++ b/encoding/prototext/encode.go
@@ -88,13 +88,10 @@
// Handle known fields.
fieldDescs := messageDesc.Fields()
- knownFields := m.KnownFields()
size := fieldDescs.Len()
for i := 0; i < size; i++ {
fd := fieldDescs.Get(i)
- num := fd.Number()
-
- if !knownFields.Has(num) {
+ if !m.Has(fd) {
continue
}
@@ -103,7 +100,7 @@
if fd.Kind() == pref.GroupKind {
name = text.ValueOf(fd.Message().Name())
}
- pval := knownFields.Get(num)
+ pval := m.Get(fd)
var err error
msgFields, err = o.appendField(msgFields, name, pval, fd)
if !nerr.Merge(err) {
@@ -113,17 +110,14 @@
// Handle extensions.
var err error
- msgFields, err = o.appendExtensions(msgFields, knownFields)
+ msgFields, err = o.appendExtensions(msgFields, m)
if !nerr.Merge(err) {
return text.Value{}, err
}
// Handle unknown fields.
// TODO: Provide option to exclude or include unknown fields.
- m.UnknownFields().Range(func(_ pref.FieldNumber, raw pref.RawFields) bool {
- msgFields = appendUnknown(msgFields, raw)
- return true
- })
+ msgFields = appendUnknown(msgFields, m.GetUnknown())
return text.ValueOf(msgFields), nerr.E
}
@@ -259,30 +253,29 @@
}
// appendExtensions marshals extension fields and appends them to the given [][2]text.Value.
-func (o MarshalOptions) appendExtensions(msgFields [][2]text.Value, knownFields pref.KnownFields) ([][2]text.Value, error) {
- xtTypes := knownFields.ExtensionTypes()
- xtFields := make([][2]text.Value, 0, xtTypes.Len())
-
+func (o MarshalOptions) appendExtensions(msgFields [][2]text.Value, m pref.Message) ([][2]text.Value, error) {
var nerr errors.NonFatal
var err error
- xtTypes.Range(func(xt pref.ExtensionType) bool {
- name := xt.Descriptor().FullName()
+ var entries [][2]text.Value
+ m.Range(func(fd pref.FieldDescriptor, v pref.Value) bool {
+ if !fd.IsExtension() {
+ return true
+ }
+ xt := fd.(pref.ExtensionType)
+
// If extended type is a MessageSet, set field name to be the message type name.
+ name := xt.Descriptor().FullName()
if isMessageSetExtension(xt) {
name = xt.Descriptor().Message().FullName()
}
- num := xt.Descriptor().Number()
- if knownFields.Has(num) {
- // Use string type to produce [name] format.
- tname := text.ValueOf(string(name))
- pval := knownFields.Get(num)
- xtFields, err = o.appendField(xtFields, tname, pval, xt.Descriptor())
- if !nerr.Merge(err) {
- return false
- }
- err = nil
+ // Use string type to produce [name] format.
+ tname := text.ValueOf(string(name))
+ entries, err = o.appendField(entries, tname, v, xt)
+ if !nerr.Merge(err) {
+ return false
}
+ err = nil
return true
})
if err != nil {
@@ -290,10 +283,10 @@
}
// Sort extensions lexicographically and append to output.
- sort.SliceStable(xtFields, func(i, j int) bool {
- return xtFields[i][0].String() < xtFields[j][0].String()
+ sort.SliceStable(entries, func(i, j int) bool {
+ return entries[i][0].String() < entries[j][0].String()
})
- return append(msgFields, xtFields...), nerr.E
+ return append(msgFields, entries...), nerr.E
}
// isMessageSetExtension reports whether extension extends a message set.
@@ -347,11 +340,14 @@
// marshalAny converts a google.protobuf.Any protoreflect.Message to a text.Value.
func (o MarshalOptions) marshalAny(m pref.Message) (text.Value, error) {
- var nerr errors.NonFatal
- knownFields := m.KnownFields()
- typeURL := knownFields.Get(fieldnum.Any_TypeUrl).String()
- value := knownFields.Get(fieldnum.Any_Value)
+ fds := m.Descriptor().Fields()
+ fdType := fds.ByNumber(fieldnum.Any_TypeUrl)
+ fdValue := fds.ByNumber(fieldnum.Any_Value)
+ typeURL := m.Get(fdType).String()
+ value := m.Get(fdValue)
+
+ var nerr errors.NonFatal
emt, err := o.Resolver.FindMessageByURL(typeURL)
if !nerr.Merge(err) {
return text.Value{}, err