p2panda-net 0.6.0

Data-type-agnostic p2p networking, discovery, gossip and local-first sync
Documentation

p2panda-net is a collection of Rust modules providing solutions for a whole set of peer-to-peer and local-first application requirements. Collectively these modules solve the problem of event delivery.

Applications subscribe to any topic they are interested in and p2panda-net will automatically discover similar peers and exchange messages between them.

🚧 This library is under active development and the APIs are not yet considered stable for production use. Core data types and user-facing APIs may still undergo breaking changes. Stability guarantees will improve with the release of v1.0.0.

Features

  • Publish & Subscribe for ephemeral messages (gossip protocol)
  • Publish & Subscribe for messages with Eventual Consistency guarantee (sync protocol)
  • Confidentially discover nodes who are interested in the same topic (Private Set Intersection)
  • Establish and manage direct connections to any device over the Internet (using iroh)
  • Monitor system with supervisors and restart modules on critical failure (Erlang-inspired Supervision Trees)
  • Modular API allowing users to choose or replace the layers they want to use

Getting Started

Install the Rust crate using cargo add p2panda-net.

use futures_util::StreamExt;
use p2panda_core::Hash;
use p2panda_net::iroh_mdns::MdnsDiscoveryMode;
use p2panda_net::{AddressBook, Discovery, Endpoint, MdnsDiscovery, Gossip};

// Topics are used to discover other nodes and establish connections around them.
let topic = Hash::digest(b"shirokuma-cafe").into();

// Maintain an address book of newly discovered or manually added nodes.
let address_book = AddressBook::builder().spawn().await?;

// Establish direct connections to any device with the help of iroh.
let endpoint = Endpoint::builder(address_book.clone())
    .spawn()
    .await?;

// Discover nodes on your local-area network.
let mdns = MdnsDiscovery::builder(address_book.clone(), endpoint.clone())
    .mode(MdnsDiscoveryMode::Active)
    .spawn()
    .await?;

// Confidentially discover nodes interested in the same topic.
let discovery = Discovery::builder(address_book.clone(), endpoint.clone())
    .spawn()
    .await?;

// Disseminate messages among nodes.
let gossip = Gossip::builder(address_book.clone(), endpoint.clone())
    .spawn()
    .await?;

// Join topic to publish and subscribe to stream of (ephemeral) messages.
let cafe = gossip.stream(topic).await?;

// This message will be seen by other nodes if they're online. If you want messages to arrive
// eventually, even when they've been offline, you need to use p2panda's "sync" module.
cafe.publish(b"Hello, Panda!").await?;

let mut rx = cafe.subscribe();
tokio::spawn(async move {
    while let Some(Ok(bytes)) = rx.next().await {
        println!("{}", String::from_utf8(bytes).expect("valid UTF-8 string"));
    }
});

For a complete command-line application using p2panda-net with a sync protocol, see our chat.rs example.

License

Licensed under either of Apache License, Version 2.0 or MIT license at your option.

Unless you explicitly state otherwise, any contribution intentionally submitted for inclusion in p2panda by you, as defined in the Apache-2.0 license, shall be dual licensed as above, without any additional terms or conditions.

This project has received funding from the European Union’s Horizon 2020 research and innovation programme within the framework of the NGI-POINTER Project funded under grant agreement No 871528, NGI-ASSURE No 957073, NGI0-ENTRUST No 101069594 and NGI0-COMMONS No 101135429.