rkyv_codec

Simple async codec for rkyv. Reuses streaming buffer for maximum speed!

This crate provides a makeshift adaptor for streaming &Archived<Object>s from an AsyncRead using a reusable external buffer, as well as a futures::Sink implementation to serialize Objects to an AsyncWrite. It uses multiformat's unsigned_varint for variable-length length encoding by default, but allows for other kinds of length encoding through the LengthEncoding trait. It also supports directly using bytes::BytesMut and #[no_std] when default features are disabled.

Examples

This crate has three examples: chatclient, chatserver & no-std. Run the first two at the same time to see a proof-of-concept Archive tcp echo server in action.

To run:

cargo run --example chat_client

cargo run --example chat_server

Simple usage example: ```rust

[derive(Archive, Deserialize, Serialize, Debug, PartialEq, Clone)]

[archive(checkbytes)] // checkbytes is required

[archive_attr(derive(Debug))]

struct Test { int: u8, string: String, option: Option>, } let value = Test { int: 42, string: "hello world".tostring(), option: Some(vec![1, 2, 3, 4]), }; // Writing let writer = Vec::new(); let mut codec = RkyvWriter::<_, VarintLength>::new(writer); codec.send(&value).await.unwrap(); // Reading let mut reader = &codec.inner()[..]; let mut buffer = AlignedVec::new(); // Aligned streaming buffer for re-use let data: &Archived = archivestream::<_, Test, VarintLength>(&mut reader, &mut buffer).await.unwrap(); // This returns a reference into the passed buffer let valuereceived: Test = data.deserialize(&mut Infallible).unwrap(); asserteq!(value, value_received); ```

See examples/no-std for an example with no-std support.

Benchmarks

These are a set of benchmarks, each benchmark represents 50 test objects being either sent or received. (requires nightly) test tests::bench_archive_sink_50 ... bench: 10,388 ns/iter (+/- 1,603) test tests::bench_archive_sink_prearchived_50 ... bench: 2,032 ns/iter (+/- 302) test tests::bench_archive_stream_50 ... bench: 3,544 ns/iter (+/- 438) test tests::bench_futures_cbor_sink_50 ... bench: 14,105 ns/iter (+/- 1,160) test tests::bench_futures_cbor_stream_50 ... bench: 9,632 ns/iter (+/- 1,437) test tests::bench_rkyv_futures_codec_sink_50 ... bench: 6,671 ns/iter (+/- 521) test tests::bench_rkyv_futures_codec_stream_50 ... bench: 4,925 ns/iter (+/- 948) test tests::bench_rkyv_writer_50 ... bench: 3,547 ns/iter (+/- 271) test tests::bench_u64_length_encoding ... bench: 4,226 ns/iter (+/- 327) test tests::bench_varint_length_encoding ... bench: 4,243 ns/iter (+/- 343) The fastest real benchmark (full serialization and bytecheck) is using RkyvWriter for writing and archive_stream for reading. This is compared to the slowest benchmark: futures_codec library's CborCodec.

Feel free to contribute your own benchmarks!