Struct MessageOptions 

pub struct MessageOptions {
    pub message_set_wire_format: Option<bool>,
    pub no_standard_descriptor_accessor: Option<bool>,
    pub deprecated: Option<bool>,
    pub map_entry: Option<bool>,
    pub deprecated_legacy_json_field_conflicts: Option<bool>,
    pub features: MessageField<FeatureSet>,
    pub uninterpreted_option: Vec<UninterpretedOption>,
    /* private fields */
}

Fields

message_set_wire_format: Option<bool>

Set true to use the old proto1 MessageSet wire format for extensions. This is provided for backwards-compatibility with the MessageSet wire format. You should not use this for any other reason: It’s less efficient, has fewer features, and is more complicated.

The message must be defined exactly as follows: message Foo {

option message_set_wire_format = true;
extensions 4 to max;

} Note that the message cannot have any defined fields; MessageSets only have extensions.

All extensions of your type must be singular messages; e.g. they cannot be int32s, enums, or repeated messages.

Because this is an option, the above two restrictions are not enforced by the protocol compiler.

Field 1: message_set_wire_format

no_standard_descriptor_accessor: Option<bool>

Disables the generation of the standard “descriptor()” accessor, which can conflict with a field of the same name. This is meant to make migration from proto1 easier; new code should avoid fields named “descriptor”.

Field 2: no_standard_descriptor_accessor

deprecated: Option<bool>

Is this message deprecated? Depending on the target platform, this can emit Deprecated annotations for the message, or it will be completely ignored; in the very least, this is a formalization for deprecating messages.

Field 3: deprecated

map_entry: Option<bool>

Whether the message is an automatically generated map entry type for the maps field.

For maps fields:

map<KeyType, ValueType> map_field = 1;

The parsed descriptor looks like:

message MapFieldEntry {
    option map_entry = true;
    optional KeyType key = 1;
    optional ValueType value = 2;
}
repeated MapFieldEntry map_field = 1;

Implementations may choose not to generate the map_entry=true message, but use a native map in the target language to hold the keys and values. The reflection APIs in such implementations still need to work as if the field is a repeated message field.

NOTE: Do not set the option in .proto files. Always use the maps syntax instead. The option should only be implicitly set by the proto compiler parser.

Field 7: map_entry

deprecated_legacy_json_field_conflicts: Option<bool>

Enable the legacy handling of JSON field name conflicts. This lowercases and strips underscored from the fields before comparison in proto3 only. The new behavior takes json_name into account and applies to proto2 as well.

This should only be used as a temporary measure against broken builds due to the change in behavior for JSON field name conflicts.

TODO This is legacy behavior we plan to remove once downstream teams have had time to migrate.

Field 11: deprecated_legacy_json_field_conflicts

features: MessageField<FeatureSet>

Any features defined in the specific edition. WARNING: This field should only be used by protobuf plugins or special cases like the proto compiler. Other uses are discouraged and developers should rely on the protoreflect APIs for their client language.

Field 12: features

uninterpreted_option: Vec<UninterpretedOption>

The parser stores options it doesn’t recognize here. See above.

Field 999: uninterpreted_option

Implementations

impl MessageOptions

pub const TYPE_URL: &'static str = "type.googleapis.com/google.protobuf.MessageOptions"

Protobuf type URL for this message, for use with Any::pack and Any::unpack_if.

Format: type.googleapis.com/<fully.qualified.TypeName>

Trait Implementations

impl Clone for MessageOptions

fn clone(&self) -> MessageOptions

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for MessageOptions

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Default for MessageOptions

fn default() -> MessageOptions

Returns the “default value” for a type.

impl DefaultInstance for MessageOptions

fn default_instance() -> &'static Self

Return a reference to the single default instance of this type.

impl ExtensionSet for MessageOptions

const PROTO_FQN: &'static str = "google.protobuf.MessageOptions"

Fully-qualified proto type name of this message (no leading dot), e.g. "google.protobuf.FieldOptions".

fn unknown_fields(&self) -> &UnknownFields

Immutable access to the extendee’s unknown-field storage.

fn unknown_fields_mut(&mut self) -> &mut UnknownFields

Mutable access to the extendee’s unknown-field storage.

fn extension<C>(&self, ext: &Extension<C>) -> <C as ExtensionCodec>::Output

where C: ExtensionCodec,

Read an extension value.

fn set_extension<C>( &mut self, ext: &Extension<C>, value: <C as ExtensionCodec>::Value, )

where C: ExtensionCodec,

Write an extension value, replacing any prior occurrences.

fn has_extension<C>(&self, ext: &Extension<C>) -> bool

where C: ExtensionCodec,

Returns true if any record at the extension’s field number is present.

fn clear_extension<C>(&mut self, ext: &Extension<C>)

where C: ExtensionCodec,

Remove all records at the extension’s field number.

fn extension_or_default<C>( &self, ext: &Extension<C>, ) -> <C as ExtensionCodec>::Value

where C: ExtensionCodec<Output = Option<<C as ExtensionCodec>::Value>>, <C as ExtensionCodec>::Value: Default,

Read a singular extension value, returning the proto2 [default = ...] value if absent, or the type’s Default if no proto default was declared.

impl Message for MessageOptions

fn compute_size(&self, __cache: &mut SizeCache) -> u32

Returns the total encoded size in bytes.

The result is a u32; the protobuf specification requires all messages to fit within 2 GiB (2,147,483,647 bytes), so a compliant message will never overflow this type.

fn write_to(&self, __cache: &mut SizeCache, buf: &mut impl BufMut)

Write this message’s encoded bytes to a buffer, consuming nested-message sizes from cache (populated by a prior compute_size call on the same cache).

fn merge_field( &mut self, tag: Tag, buf: &mut impl Buf, depth: u32, ) -> Result<(), DecodeError>

Processes a single already-decoded tag and its associated field data from buf.

fn clear(&mut self)

Clear all fields to their default values.

fn encode(&self, buf: &mut impl BufMut)

Compute size, then write. This is the primary encoding API.

fn encode_with_cache(&self, cache: &mut SizeCache, buf: &mut impl BufMut)

Encode using a caller-supplied SizeCache, for reuse across many encodes in a hot loop. Clears the cache first.

fn encoded_len(&self) -> u32

Compute the encoded byte size of this message.

fn encode_length_delimited(&self, buf: &mut impl BufMut)

Encode this message as a length-delimited byte sequence.

fn encode_to_vec(&self) -> Vec<u8>

Encode this message to a new Vec<u8>.

fn encode_to_bytes(&self) -> Bytes

Encode this message to a new bytes::Bytes.

fn decode(buf: &mut impl Buf) -> Result<Self, DecodeError>

where Self: Sized,

Decode a message from a buffer.

fn decode_from_slice(data: &[u8]) -> Result<Self, DecodeError>

where Self: Sized,

Decode a message from a byte slice.

fn decode_length_delimited(buf: &mut impl Buf) -> Result<Self, DecodeError>

where Self: Sized,

Decode a length-delimited message from a buffer.

fn merge_to_limit( &mut self, buf: &mut impl Buf, depth: u32, limit: usize, ) -> Result<(), DecodeError>

Merge fields from a buffer until buf.remaining() reaches limit.

fn merge_group( &mut self, buf: &mut impl Buf, depth: u32, field_number: u32, ) -> Result<(), DecodeError>

Merges a group-encoded message from buf, reading fields until an EndGroup tag with the given field_number is encountered.

fn merge(&mut self, buf: &mut impl Buf, depth: u32) -> Result<(), DecodeError>

Merge fields from a buffer into this message.

fn merge_from_slice(&mut self, data: &[u8]) -> Result<(), DecodeError>

Merge fields from a byte slice into this message.

fn merge_length_delimited( &mut self, buf: &mut impl Buf, depth: u32, ) -> Result<(), DecodeError>

Merge fields from a length-delimited sub-message payload into this message.

impl PartialEq for MessageOptions

fn eq(&self, other: &MessageOptions) -> bool

Tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Rhs) -> bool

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl StructuralPartialEq for MessageOptions