Struct AnyCopy item path

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

§Example

let duration = Duration::clamp(123, 456);
let any = Any::from_msg(&duration)?;
let extracted = any.to_msg::<Duration>()?;
assert_eq!(extracted, duration);
let fail = any.to_msg::<Timestamp>();
assert!(matches!(fail, Err(AnyError::TypeMismatch{..})));

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

§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"
    }