Crate kinship 

SWIM membership and failure detection with Lifeguard, for Rust and Python.

Cluster runs one node on the current tokio runtime: it binds UDP and TCP on one port, joins the configured seeds and keeps the membership view current while the application reads members and listens to events.

use kinship::{Cluster, Config, Event, Key};
use std::time::Duration;

let cfg = Config::lan()
    .with_name("worker-17")
    .with_keys([Key::from_base64(&std::env::var("KINSHIP_KEY")?)?])
    .with_seeds(["10.0.0.5:7946".parse()?]);
let cluster = Cluster::start(cfg).await?; // binds, joins seeds
let mut events = cluster.events();
while let Some(event) = events.recv().await {
    match event {
        Event::MemberDead(m) | Event::MemberLeft(m) => println!("{} is gone", m.name),
        Event::UserMessage { sender, data, .. } => println!("{}: {data:?}", sender.name),
        Event::EventsLost(_) => println!("resync: {} members", cluster.members().len()),
        _ => {}
    }
}
cluster.leave(Duration::from_secs(5)).await?;
cluster.close().await;

Modules

mem

An in-memory Transport for tests: datagrams and streams between nodes in one process, with no sockets.

Structs

Cluster

A running cluster member.

Config

Everything a Cluster needs, built from a preset with with_* setters.

ConfigError

A Config or Identity field holds an unusable value.

CoreConfig

The protocol half of Config, from kinship-core. Everything the protocol needs to know that is not an input.

Events

One subscription to a node’s events, from Memberlist::events.

Key

A 32-byte XChaCha20-Poly1305 key. Zeroized on drop and never printed.

KeyId

The public id of a Key: safe to log, and printed as 8 hex characters.

Keyring

Runtime key rotation for one node, from Memberlist::keyring.

Member

One member as this node sees it.

Metrics

Monotonic counters since the node started.

SeedError

A seed that is not host:port with an IP address or a DNS name.

Stats

Counters from the protocol core and this node’s Lifeguard local health score.

TokioTransport

UDP and TCP sockets from tokio, sharing one port.

Enums

Error

Why a call on a Memberlist failed.

Event

Something the application should hear about. Member events never describe the local node; NameConflict may.

KeyError

Text given as a key could not be turned into one.

Seed

A seed: an address, or a host name and port that is looked up at every join and rejoin.

State

Where a member stands in this node’s view.

Constants

DEFAULT_PORT

Default port for UDP and TCP.

WIRE_VERSION

Wire format version spoken by this build.

Traits

Transport

One node’s datagram endpoint and stream listener, both on the same address.

Functions

generate_key

A new random key: 32 bytes from the operating system’s secure random source.