iroh-docs

Multi-dimensional key-value documents with an efficient synchronization protocol.

The crate operates on Replicas. A replica contains an unlimited number of Entries. Each entry is identified by a key, its author, and the replica's namespace. Its value is the 32-byte BLAKE3 hash of the entry's content data, the size of this content data, and a timestamp. The content data itself is not stored or transferred through a replica.

All entries in a replica are signed with two keypairs:

• The Namespace key, as a token of write capability. The public key is the NamespaceId, which also serves as the unique identifier for a replica.
• The Author key, as a proof of authorship. Any number of authors may be created, and their semantic meaning is application-specific. The public key of an author is the [AuthorId].

Replicas can be synchronized between peers by exchanging messages. The synchronization algorithm is based on a technique called range-based set reconciliation, based on this paper by Aljoscha Meyer:

Range-based set reconciliation is a simple approach to efficiently compute the union of two sets over a network, based on recursively partitioning the sets and comparing fingerprints of the partitions to probabilistically detect whether a partition requires further work.

The crate exposes a generic storage interface with in-memory and persistent, file-based implementations. The latter makes use of [redb], an embedded key-value store, and persists the whole store with all replicas to a single file.

Getting Started

The entry into the iroh-docs protocol is the Docs struct, which uses an Engine to power the protocol.

Docs was designed to be used in conjunction with iroh. Iroh is a networking library for making direct connections, these connections are peers send sync messages and transfer data.

Iroh provides a Router that takes an Endpoint and any protocols needed for the application. Similar to a router in webserver library, it runs a loop accepting incoming connections and routes them to the specific protocol handler, based on ALPN.

Docs is a "meta protocol" that relies on the iroh-blobs and iroh-gossip protocols. Setting up Docs will require setting up Blobs and Gossip as well.

Here is a basic example of how to set up iroh-docs with iroh:

use iroh::{protocol::Router, Endpoint};
use iroh_blobs::{net_protocol::Blobs, util::local_pool::LocalPool, ALPN as BLOBS_ALPN};
use iroh_docs::{protocol::Docs, ALPN as DOCS_ALPN};
use iroh_gossip::{net::Gossip, ALPN as GOSSIP_ALPN};

#[tokio::main]
async fn main() -> anyhow::Result<()> {
    // create an iroh endpoint that includes the standard discovery mechanisms
    // we've built at number0
    let endpoint = Endpoint::builder().discovery_n0().bind().await?;

    // create a router builder, we will add the
    // protocols to this builder and then spawn
    // the router
    let builder = Router::builder(endpoint);

    // build the blobs protocol
    let local_pool = LocalPool::default();
    let blobs = Blobs::memory().build(local_pool.handle(), builder.endpoint());

    // build the gossip protocol
    let gossip = Gossip::builder().spawn(builder.endpoint().clone()).await?;

    // build the docs protocol
    let docs = Docs::memory().spawn(&blobs, &gossip).await?;

    // setup router
    let router = builder
        .accept(BLOBS_ALPN, blobs)
        .accept(GOSSIP_ALPN, gossip)
        .accept(DOCS_ALPN, docs)
        .spawn()
        .await?;

    // do fun stuff with docs!
    Ok(())
}

License

This project is licensed under either of

• Apache License, Version 2.0, (LICENSE-APACHE or http://www.apache.org/licenses/LICENSE-2.0)
• MIT license (LICENSE-MIT or http://opensource.org/licenses/MIT)

at your option.

Contribution

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