Kyoto: Bitcoin Light Client

An Implementation of BIP-157/BIP-158

Crate Info MIT or Apache-2.0 Licensed CI Status API Docs Rustc Version 1.63.0+

## About Kyoto is aiming to be a simple, memory-conservative, and private Bitcoin client for developers to build wallet applications. To read more about the scope, usage recommendations, and implementation details, see [DETAILS.md](./doc/DETAILS.md). ## Running an example To run the Signet example, in the root directory: ``` cargo run --example signet ``` Or, with `just`: ``` just example ``` ## Getting Started The following snippet demonstrates how to build a Kyoto node. See the [docs](https://docs.rs/kyoto-cbf) for more details on the `NodeBuilder`, `Node`, `Client`, and more. ```rust use std::collections::HashSet; use kyoto::{NodeBuilder, NodeMessage, Address, Network, HeaderCheckpoint, BlockHash, TrustedPeer}; let address = Address::from_str("tb1q9pvjqz5u5sdgpatg3wn0ce438u5cyv85lly0pc") .unwrap() .require_network(Network::Signet) .unwrap() .into(); let mut addresses = HashSet::new(); addresses.insert(address); let builder = NodeBuilder::new(bitcoin::Network::Signet); // Add node preferences and build the node/client let (mut node, mut client) = builder // Add the peers .add_peers(vec![TrustedPeer::from_ip(peer_1), TrustedPeer::from_ip(peer_1)]) // The Bitcoin scripts to monitor .add_scripts(addresses) // Only scan blocks strictly after an anchor checkpoint .anchor_checkpoint(HeaderCheckpoint::new( 180_000, BlockHash::from_str("0000000870f15246ba23c16e370a7ffb1fc8a3dcf8cb4492882ed4b0e3d4cd26") .unwrap(), )) // The number of connections we would like to maintain .num_required_peers(2) // Create the node and client .build_node() .unwrap(); ``` ## Minimum Supported Rust Version (MSRV) Policy The `kyoto` core library with default features supports an MSRV of Rust 1.63. To build the library with Rust 1.63, the `database` feature requires a pinned dependency: `cargo update -p allocator-api2 --precise "0.2.9"`. While connections over the Tor protocol are supported by the feature `tor`, the dependencies required cannot support the MSRV. As such, no MSRV guarantees will be made when using Tor, and the feature should be considered experimental. ## Integration Testing The preferred workflow is by using `just`. If you do not have `just` installed, check out the [installation page](https://just.systems/man/en/chapter_4.html). To run the unit tests: ``` just test ``` To sync with a live Signet node: ``` just sync ``` And to run scenarios against your `bitcoind` instance: ``` just integrate ``` The default path to the `.bitcoin` directory is for Linux. To set this path to another operating system or location: ``` just bitcoindir=/path/to/bitcoin/folder/ integrate ``` ## Project Layout `chain`: Contains all logic for syncing block headers, filter headers, filters, parsing blocks. Also contains preset checkpoints for Signet, Regtest, and Bitcoin networks. Notable files: `chain.rs` `core`: Organizes the primary user-facing components of the API. This includes both the `Node` and the `Client` that all developers will interact with, as well as the `NodeBuilder`. Importantly includes `peer_map.rs`, which is the primary file that handles peer threads by sending messages, persisting new peers, banning peers, and managing peer task handles. `node.rs` is the main application loop, responsible for driving the node actions. Notable files: `node.rs`, `peer_map.rs`, `builder.rs`, `client.rs` `db`: Defines how data must be persisted with `traits.rs`, and includes some opinionated defaults for database components. `filters`: Additional structures for managing compact filter headers and filters, used by `chain.rs` `network`: Opens and closes connections, handles encryption and decryption of messages, generates messages, parses messages, times message response times, performs DNS lookups. Notable files: `peer.rs`, `reader.rs`, `parsers.rs`, `outbound_messages.rs` ## Contributing Please read [CONTRIBUTING.md](./CONTRIBUTING.md) to get started. Unless you explicitly state otherwise, any contribution intentionally submitted for inclusion in the work by you, as defined in the Apache-2.0 license, shall be dual licensed as above, without any additional terms or conditions. ## License Licensed under either of * Apache License, Version 2.0, ([LICENSE-APACHE](LICENSE-APACHE) or ) * MIT license ([LICENSE-MIT](LICENSE-MIT) or ) at your option.