bytes VS prost

Many Rust code examples I come across online represent bytes as &[u8] or Vec. However, there is a Bytes crate. Is there any reason for preferring the vector or the slice instead of this crate for bytes?

Take a look at the Bytes crate. With it, one can buffer bytes into a BufMut, and send borrowed slices as Bytes. Once the Bytes are freed, the BufMut takes care of reusing the capacity. Several of the web server frameworks use this, so it's fairly mature.

The project is led by the Tokio community — most of the implementation so far has been done by people who are Tokio project maintainers. Tokio hosts a number of libraries that aren't tightly coupled to the tokio crate's runtime, like prost and bytes. The name just means that the same group of people is committed to working on and maintaining it. :)

Oh an libraries (or the std library) that want to write unsafe code that relies on some Trait's invariant will mark that trait `unsafe`, for example: https://github.com/tokio-rs/bytes/pull/432

The benchmark is not comparing apples to apples.

prost is the most widely used Protobuf implementation in Rust, maintained by the Tokio organization. prost generates structs and serialization/deserialization code for you.

easyproto according to GitHib Search is used only by two projects. easyproto provides primitives for serializing and deserializing Protobuf, and requires hand writing code to do both.

A fair comparison would be prost vs google.golang.org/protobuf, or easyproto vs parts of quick-protobuf.

In most cases you can make Go as fast as Rust, but from my experience writing performance-sensitive code in Go requires significantly larger time investment and overall requires deeper language expertise. Pebble (RocksDB replacement in Go by CockroachDB) is a good example of this, the codebase is littered with hand-inlined[1] functions, hand-unrolled loops and it's not[2] even using Go memory management for performance critical parts, it's using the C memory allocator and manual memory management.

[prost]: https://github.com/tokio-rs/prost

You could use Protocol buffers to define a message type, then use prost to generate encoding/decoding code for that type.

Thanks but that doesn't seems to support `json_mapping` , there is a draft available but not sure when it will get merged https://github.com/tokio-rs/prost/pull/558

Hi r/rust, I have a question regarding tonic-build (or prost-build).

Currently, I'm making some stuff by using protobuf via prost. Maybe you know, protobuf v3 treats all fields as optional, so it is pain to unwrap every nested field.

Note: one additional key feature currently missing from Prost is Proto2 extensions.