Struct Any 

pub struct Any {
    pub type_url: String,
    pub value: Vec<u8>,
    /* private fields */
}

Any contains an arbitrary serialized protocol buffer message along with a URL that describes the type of the serialized message.

Protobuf library provides support to pack/unpack Any values in the form of utility functions or additional generated methods of the Any type.

Example 1: Pack and unpack a message in C++.

Foo foo = ...;
Any any;
any.PackFrom(foo);
...
if (any.UnpackTo(&foo)) {
  ...
}

Example 2: Pack and unpack a message in Java.

Foo foo = ...;
Any any = Any.pack(foo);
...
if (any.is(Foo.class)) {
  foo = any.unpack(Foo.class);
}
// or ...
if (any.isSameTypeAs(Foo.getDefaultInstance())) {
  foo = any.unpack(Foo.getDefaultInstance());
}

Example 3: Pack and unpack a message in Python.

foo = Foo(...)
any = Any()
any.Pack(foo)
...
if any.Is(Foo.DESCRIPTOR):
  any.Unpack(foo)
  ...

Example 4: Pack and unpack a message in Go

 foo := &pb.Foo{...}
 any, err := anypb.New(foo)
 if err != nil {
   ...
 }
 ...
 foo := &pb.Foo{}
 if err := any.UnmarshalTo(foo); err != nil {
   ...
 }

The pack methods provided by protobuf library will by default use ‘type.googleapis.com/full.type.name’ as the type URL and the unpack methods only use the fully qualified type name after the last ‘/’ in the type URL, for example “foo.bar.com/x/y.z” will yield type name “y.z”.

JSON

The JSON representation of an Any value uses the regular representation of the deserialized, embedded message, with an additional field @type which contains the type URL. Example:

package google.profile;
message Person {
  string first_name = 1;
  string last_name = 2;
}

{
  "@type": "type.googleapis.com/google.profile.Person",
  "firstName": <string>,
  "lastName": <string>
}

If the embedded message type is well-known and has a custom JSON representation, that representation will be embedded adding a field value which holds the custom JSON in addition to the @type field. Example (for message [google.protobuf.Duration][]):

{
  "@type": "type.googleapis.com/google.protobuf.Duration",
  "value": "1.212s"
}

Fields

type_url: String

A URL/resource name that uniquely identifies the type of the serialized protocol buffer message. This string must contain at least one “/” character. The last segment of the URL’s path must represent the fully qualified name of the type (as in path/google.protobuf.Duration). The name should be in a canonical form (e.g., leading “.” is not accepted).

In practice, teams usually precompile into the binary all types that they expect it to use in the context of Any. However, for URLs which use the scheme http, https, or no scheme, one can optionally set up a type server that maps type URLs to message definitions as follows:

• If no scheme is provided, https is assumed.
• An HTTP GET on the URL must yield a [google.protobuf.Type][] value in binary format, or produce an error.
• Applications are allowed to cache lookup results based on the URL, or have them precompiled into a binary to avoid any lookup. Therefore, binary compatibility needs to be preserved on changes to types. (Use versioned type names to manage breaking changes.)

Note: this functionality is not currently available in the official protobuf release, and it is not used for type URLs beginning with type.googleapis.com. As of May 2023, there are no widely used type server implementations and no plans to implement one.

Schemes other than http, https (or the empty scheme) might be used with implementation specific semantics.

Field 1: type_url

value: Vec<u8>

Must be a valid serialized protocol buffer of the above specified type.

Field 2: value

Implementations

impl Any

pub fn pack(msg: &impl Message, type_url: impl Into<String>) -> Self

Pack a message into an Any with the given type URL.

The type URL is conventionally of the form type.googleapis.com/fully.qualified.TypeName, but this method does not enforce that convention — any string is accepted.

pub fn unpack_unchecked<T: Message>(&self) -> Result<T, DecodeError>

Unpack the contained message, decoding its bytes as T, without checking the type_url.

This method always attempts to decode the payload as T regardless of whether type_url actually identifies T. Use Any::unpack_if when you need to verify the stored type before decoding.

Errors

Returns a buffa::DecodeError if the bytes cannot be decoded as T.

pub fn unpack_if<T: Message>( &self, expected_type_url: &str, ) -> Result<Option<T>, DecodeError>

Unpack the contained message as T, but only if the type_url matches expected_type_url.

Returns Ok(None) when the type URL does not match.

Errors

Returns a buffa::DecodeError if the type URL matches but the bytes cannot be decoded as T.

pub fn is_type(&self, type_url: &str) -> bool

Returns true if this Any’s type_url matches the given string.

pub fn type_url(&self) -> &str

Returns the type URL stored in this Any.

impl Any

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

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<'arbitrary> Arbitrary<'arbitrary> for Any

fn arbitrary(u: &mut Unstructured<'arbitrary>) -> Result<Self>

Generate an arbitrary value of Self from the given unstructured data.

fn arbitrary_take_rest(u: Unstructured<'arbitrary>) -> Result<Self>

Generate an arbitrary value of Self from the entirety of the given unstructured data.

fn size_hint(depth: usize) -> (usize, Option<usize>)

Get a size hint for how many bytes out of an Unstructured this type needs to construct itself.

fn try_size_hint( depth: usize, ) -> Result<(usize, Option<usize>), MaxRecursionReached>

Get a size hint for how many bytes out of an Unstructured this type needs to construct itself.

impl Clone for Any

fn clone(&self) -> Any

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for Any

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

Formats the value using the given formatter.

impl Default for Any

fn default() -> Any

Returns the “default value” for a type.

impl DefaultInstance for Any

fn default_instance() -> &'static Self

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

impl<'de> Deserialize<'de> for Any

Available on crate feature json only.

fn deserialize<D: Deserializer<'de>>(d: D) -> Result<Self, D::Error>

Deserialize this value from the given Serde deserializer.

impl ExtensionSet for Any

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

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 Any

fn compute_size(&self) -> 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, buf: &mut impl BufMut)

Write this message’s encoded bytes to a buffer.

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 cached_size(&self) -> u32

The cached encoded size from the last compute_size() call.

fn clear(&mut self)

Clear all fields to their default values.

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

Convenience: compute size, then write. This is the primary encoding API.

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 Any

fn eq(&self, other: &Any) -> 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 Serialize for Any

Available on crate feature json only.

fn serialize<S: Serializer>(&self, s: S) -> Result<S::Ok, S::Error>

Serialize this value into the given Serde serializer.

impl TextFormat for Any

fn encode_text(&self, enc: &mut TextEncoder<'_>) -> Result

Write this message’s fields to enc.

fn merge_text(&mut self, dec: &mut TextDecoder<'_>) -> Result<(), ParseError>

Merge fields from dec into this message.

impl StructuralPartialEq for Any