p2panda-net

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

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.

[!IMPORTANT] p2panda-net depends on a fixed version (#117) of iroh-gossip which has not been published yet.

Please patch your build with the fixed crate for now until this is handled upstream by adding the following lines to your root Cargo.toml:

[patch.crates-io]
iroh-gossip = { git = "https://github.com/p2panda/iroh-gossip", rev = "533c34a2758518ece19c1de9f21bc40d61f9b5a5" }

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::new(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 and NGI0-ENTRUST No 101069594.