Struct FieldDescriptorProto 

pub struct FieldDescriptorProto {
    pub name: Option<String>,
    pub number: Option<i32>,
    pub label: Option<Label>,
    pub type: Option<Type>,
    pub type_name: Option<String>,
    pub extendee: Option<String>,
    pub default_value: Option<String>,
    pub oneof_index: Option<i32>,
    pub json_name: Option<String>,
    pub options: MessageField<FieldOptions>,
    pub proto3_optional: Option<bool>,
    /* private fields */
}

Describes a field within a message.

Fields

name: Option<String>

Field 1: name

number: Option<i32>

Field 3: number

label: Option<Label>

Field 4: label

type: Option<Type>

If type_name is set, this need not be set. If both this and type_name are set, this must be one of TYPE_ENUM, TYPE_MESSAGE or TYPE_GROUP.

Field 5: type

type_name: Option<String>

For message and enum types, this is the name of the type. If the name starts with a ‘.’, it is fully-qualified. Otherwise, C++-like scoping rules are used to find the type (i.e. first the nested types within this message are searched, then within the parent, on up to the root namespace).

Field 6: type_name

extendee: Option<String>

For extensions, this is the name of the type being extended. It is resolved in the same manner as type_name.

Field 2: extendee

default_value: Option<String>

For numeric types, contains the original text representation of the value. For booleans, “true” or “false”. For strings, contains the default text contents (not escaped in any way). For bytes, contains the C escaped value. All bytes >= 128 are escaped.

Field 7: default_value

oneof_index: Option<i32>

If set, gives the index of a oneof in the containing type’s oneof_decl list. This field is a member of that oneof.

Field 9: oneof_index

json_name: Option<String>

JSON name of this field. The value is set by protocol compiler. If the user has set a “json_name” option on this field, that option’s value will be used. Otherwise, it’s deduced from the field’s name by converting it to camelCase.

Field 10: json_name

options: MessageField<FieldOptions>

Field 8: options

proto3_optional: Option<bool>

If true, this is a proto3 “optional”. When a proto3 field is optional, it tracks presence regardless of field type.

When proto3_optional is true, this field must belong to a oneof to signal to old proto3 clients that presence is tracked for this field. This oneof is known as a “synthetic” oneof, and this field must be its sole member (each proto3 optional field gets its own synthetic oneof). Synthetic oneofs exist in the descriptor only, and do not generate any API. Synthetic oneofs must be ordered after all “real” oneofs.

For message fields, proto3_optional doesn’t create any semantic change, since non-repeated message fields always track presence. However it still indicates the semantic detail of whether the user wrote “optional” or not. This can be useful for round-tripping the .proto file. For consistency we give message fields a synthetic oneof also, even though it is not required to track presence. This is especially important because the parser can’t tell if a field is a message or an enum, so it must always create a synthetic oneof.

Proto2 optional fields do not set this flag, because they already indicate optional with LABEL_OPTIONAL.

Field 17: proto3_optional

Implementations

impl FieldDescriptorProto

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

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 FieldDescriptorProto

fn clone(&self) -> FieldDescriptorProto

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for FieldDescriptorProto

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

Formats the value using the given formatter.

impl Default for FieldDescriptorProto

fn default() -> FieldDescriptorProto

Returns the “default value” for a type.

impl DefaultInstance for FieldDescriptorProto

fn default_instance() -> &'static Self

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

impl ExtensionSet for FieldDescriptorProto

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

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 FieldDescriptorProto

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 FieldDescriptorProto

fn eq(&self, other: &FieldDescriptorProto) -> 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 FieldDescriptorProto