Protobuf generated structs and traits for conversion.
The central part of this module is ProtobufConvert.
The main purpose of this trait is to allow
users to create a map between their types and the types generated from .proto descriptions, while
providing a mechanism for additional validation of protobuf data.
Most of the time you do not have to implement this trait because most of the use cases are covered
by #[derive(ProtobufConvert)] from exonum_derive crate.
A typical example of such mapping with validation is manual implementation of this trait for crypto::Hash.
crypto::Hash is a fixed sized array of bytes but protobuf does not allow us to express this constraint since
only dynamically sized arrays are supported.
If you would like to use Hash as a part of your
protobuf struct, you would have to write a conversion function from protobuf proto::Hash(which
is dynamically sized array of bytes) tocrypto::Hash and call it every time when you want to
use crypto::Hash in your application.
The provided ProtobufConvert implementation for Hash allows you to embed this field into your
struct and generate ProtobufConvert for it using #[derive(ProtobufConvert)], which will validate
your struct based on the validation function for Hash.