fizyr-rpc

Rust implementation of the Fizyr RPC procotol.

The Fizyr RPC protocol is a request/response protocol, with bi-directional feedback as long as a request is open. Additionally, you can send individual stream messages that do not initiate a request.

Overview

Peer and PeerHandle

As a user of the library, you will mostly be using the PeerHandle object. The PeerHandle is used to interact with a remote peer. It is used to send and receive requests and stream messages. It can also be split in a PeerReadHandle and a PeerWriteHandle, to allow moving the handles into different tasks. The write handle can also be cloned and used in multiple tasks.

To obtain a PeerHandle, you can call Peer::connect(). This will connect to a remote listener and spawn a background task to read and write messages over the connection. If you need full control over tasks, you can instead create a Peer object and call Peer::run() manually.

Listener

The [Listener] struct is used to accept incoming connections and gives you a PeerHandle for each incoming connection. You can then use the handle to process incoming messages and to send messages to the peer. Usually, you will want to spawn a task for each accepted connection that handles the communication.

Transports

Each peer internally uses a Transport. The transport is responsible for reading and writing raw messages. By abstracting away the message transport, the library can expose a single generic Peer and [Listener] struct.

There are different transports for different socket types. Different transports may also use different types as message body. For example, the TcpTransport and UnixStreamTransport use messages with a StreamBody. This StreamBody body type contains raw bytes.

The UnixSeqpacketTransport has messages with a UnixBody, which allows you to embed file descriptors with each message.

Features

The library uses features to avoid unnecessarily large dependency trees. Each feature corresponds to a different transport type. None of the features are enabled by default. Currently, the library has these features:

• tcp: for the TcpTransport
• unix-stream: for the UnixStreamTransport
• unix-seqpacket: for the UnixSeqpacketTransport

Example

use fizyr_rpc::{TcpPeer, StreamConfig};

let (peer, info) = TcpPeer::connect("localhost:1337", StreamConfig::default()).await?;
eprintln!("Connected to: {}", info.remote_address());
let mut request = peer.send_request(1, &b"Hello World!"[..]).await?;

while let Some(update) = request.recv_update().await {
    let body = std::str::from_utf8(&update.body)?;
    eprintln!("Received update: {}", body);
}

let response = request.recv_response().await?;
let body = std::str::from_utf8(&response.body)?;
eprintln!("Received response: {}", body);