Struct Any 

pub struct Any {
    pub type_url: String,
    pub value: Bytes,
    /* 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: Bytes

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.

Panics

Panics if msg’s encoded size exceeds the 2 GiB protobuf limit (buffa::MAX_MESSAGE_BYTES) — see try_pack for the error-returning variant.

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

Pack a message into an Any, returning an error instead of panicking if the message’s encoded size exceeds the 2 GiB protobuf limit (buffa::MAX_MESSAGE_BYTES).

Errors

Returns buffa::EncodeError::MessageTooLarge if the encoded size exceeds the limit.

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 try_set_extension<C>( &mut self, ext: &Extension<C>, value: <C as ExtensionCodec>::Value, ) -> Result<(), EncodeError>

where C: ExtensionCodec,

Write an extension value, replacing any prior occurrences — returning an error instead of panicking if a message-typed value’s encoded size exceeds the 2 GiB protobuf limit (MAX_MESSAGE_BYTES).

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 HasMessageView for Any

type View<'a> = AnyView<'a>

The zero-copy view of Self, borrowing from a buffer with lifetime 'a.

type ViewHandle = AnyOwnedView

The generated 'static owned-view handle for Self (FooOwnedView).

fn decode_view(buf: &[u8]) -> Result<Self::View<'_>, DecodeError>

Decode a borrowed View from a byte slice.

fn decode_view_with_options<'a>( buf: &'a [u8], opts: &DecodeOptions, ) -> Result<Self::View<'a>, DecodeError>

Decode a borrowed View under custom DecodeOptions (recursion limit, max message size, unknown-field limit).

fn decode_view_handle(bytes: Bytes) -> Result<Self::ViewHandle, DecodeError>

Decode a ViewHandle from a Bytes buffer.

fn decode_view_handle_with_options( bytes: Bytes, opts: &DecodeOptions, ) -> Result<Self::ViewHandle, DecodeError>

Decode a ViewHandle with custom DecodeOptions (recursion limit, max message size).

impl Message for Any

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

Returns the total encoded size in bytes.

Accumulates in u64 (which cannot overflow for in-memory data) and saturates to u32 at return, so a message whose encoded size exceeds the 2 GiB protobuf limit yields a value above ::buffa::MAX_MESSAGE_BYTES that the encode entry points reject, never a silently wrapped size.

fn write_to(&self, _cache: &mut SizeCache, buf: &mut impl EncodeSink)

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, ctx: DecodeContext<'_>, ) -> 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 EncodeSink)

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

fn try_encode(&self, buf: &mut impl EncodeSink) -> Result<(), EncodeError>

Encode, returning an error instead of panicking if the encoded size exceeds the 2 GiB protobuf limit (MAX_MESSAGE_BYTES).

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

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

fn try_encode_with_cache( &self, cache: &mut SizeCache, buf: &mut impl EncodeSink, ) -> Result<(), EncodeError>

Encode with a caller-supplied SizeCache, returning an error instead of panicking if the encoded size exceeds the 2 GiB protobuf limit (MAX_MESSAGE_BYTES). Clears the cache first.

fn try_encode_bounded( &self, max_bytes: u32, buf: &mut impl EncodeSink, ) -> Result<u32, EncodeError>

Encode this message into buf only if its encoded size fits within max_bytes, using a single size pass that is then reused for the write.

fn try_encode_bounded_with_cache( &self, max_bytes: u32, cache: &mut SizeCache, buf: &mut impl EncodeSink, ) -> Result<u32, EncodeError>

Like try_encode_bounded but reuses an existing SizeCache, clearing it first.

fn encoded_len(&self) -> u32

Compute the encoded byte size of this message.

fn try_encoded_len(&self) -> Result<u32, EncodeError>

Compute the encoded byte size, returning an error instead of panicking if it exceeds the 2 GiB protobuf limit (MAX_MESSAGE_BYTES).

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

Encode this message as a length-delimited byte sequence.

fn try_encode_length_delimited( &self, buf: &mut impl EncodeSink, ) -> Result<(), EncodeError>

Encode as a length-delimited byte sequence, returning an error instead of panicking if the encoded size exceeds the 2 GiB protobuf limit (MAX_MESSAGE_BYTES).

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

Encode this message to a new Vec<u8>.

fn try_encode_to_vec(&self) -> Result<Vec<u8>, EncodeError>

Encode to a new Vec<u8>, returning an error instead of panicking if the encoded size exceeds the 2 GiB protobuf limit (MAX_MESSAGE_BYTES).

fn encode_to_bytes(&self) -> Bytes

Encode this message to a new bytes::Bytes.

fn try_encode_to_bytes(&self) -> Result<Bytes, EncodeError>

Encode to a new bytes::Bytes, returning an error instead of panicking if the encoded size exceeds the 2 GiB protobuf limit (MAX_MESSAGE_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, ctx: DecodeContext<'_>, limit: usize, ) -> Result<(), DecodeError>

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

fn merge_group( &mut self, buf: &mut impl Buf, ctx: DecodeContext<'_>, 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, ctx: DecodeContext<'_>, ) -> 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, ctx: DecodeContext<'_>, ) -> Result<(), DecodeError>

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

impl MessageName for Any

const PACKAGE: &'static str = "google.protobuf"

The protobuf package the message is declared in.

const NAME: &'static str = "Any"

The unqualified message name, with . between nesting levels.

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

The fully-qualified protobuf type name with no leading dot.

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

The google.protobuf.Any.type_url form for this message.

impl PartialEq for Any

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

Equality operator ==.

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

Inequality operator !=.

impl ReflectElement for Any

Available on crate feature reflect only.

fn as_value_ref(&self) -> ValueRef<'_>

Borrow this element as a ValueRef.

impl ReflectMessage for Any

Available on crate feature reflect only.

fn message_descriptor(&self) -> &MessageDescriptor

The descriptor for this message type.

fn pool(&self) -> &Arc<DescriptorPool>

The pool the descriptor lives in. Use this to dereference MessageIndex / EnumIndex from FieldKind, or Arc::clone it to construct sibling DynamicMessages while navigating nested fields.

fn unknown_fields(&self) -> &UnknownFields

The fields preserved from decode that the message’s descriptor does not recognize.

fn get(&self, field: &FieldDescriptor) -> ValueRef<'_>

Get a field’s value.

fn has(&self, field: &FieldDescriptor) -> bool

Whether a field is present.

fn for_each_set(&self, f: &mut dyn FnMut(&FieldDescriptor, ValueRef<'_>))

Visit every set field.

fn to_dynamic(&self) -> DynamicMessage

Snapshot this message as an owned DynamicMessage.

fn which_oneof(&self, oneof: &OneofDescriptor) -> Option<&FieldDescriptor>

Which member of oneof is set, if any.

impl Reflectable for Any

Available on crate feature reflect only.

fn reflect(&self) -> ReflectCow<'_>

Vtable-mode reflective handle: borrows self directly. No encode/decode round-trip and no allocation — the reflective accessors read this message’s fields in place.

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 StructuralPartialEq for Any

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.