<p align="center">
<img src="static/halfin.webp" width="40%" alt="A Bitcoin Node Runner (Hal Finney)">
</p>
# halfin
<p>
<a href="https://crates.io/crates/halfin"><img src="https://img.shields.io/crates/v/halfin.svg"/></a>
<a href="https://docs.rs/halfin"><img src="https://img.shields.io/badge/docs.rs-halfin-green"/></a>
<a href="https://blog.rust-lang.org/2025/02/20/Rust-1.85.0/"><img src="https://img.shields.io/badge/rustc-1.85.0%2B-orange.svg?label=MSRV"/></a>
<a href="https://github.com/luisschwab/halfin/blob/master/LICENSE"><img src="https://img.shields.io/badge/License-MIT%2FApache--2.0-red.svg"/></a>
<a href="https://github.com/luisschwab/halfin/actions/workflows/rust.yml"><img src="https://github.com/luisschwab/halfin/actions/workflows/rust.yml/badge.svg"></a>
<a href="https://github.com/luisschwab/halfin/actions/workflows/cross.yml"><img src="https://github.com/luisschwab/halfin/actions/workflows/cross.yml/badge.svg"></a>
</p>
> A {regtest} bitcoin node runner 🏃♂️
This crate makes it simple to run regtest [`bitcoind`](https://github.com/bitcoin/bitcoin)
and [`utreexod`](https://github.com/utreexo/utreexod) instances from Rust code, useful in
integration test contexts.
Pretty much [`bitcoind`](https://crates.io/crates/bitcoind) with
[`utreexod`](https://github.com/utreexo/utreexod) support.
## Supported Implementations and Versions
| `bitcoind` | `v31.0` | `bitcoind_31_0` |
| | | |
| `utreexod` | `v0.5.0` | `utreexod_0_5_0` |
By default, the `bitcoind_31_0` and `utreexod_0_5_0` features are enabled.
Binaries are downloaded automatically at build time: see [`build.rs`](./build.rs).
### BitcoinD
```rs
use halfin::connect;
use halfin::bitcoind::BitcoinD;
// Use a downloaded binary
let bitcoind_alpha = BitcoinD::new().unwrap();
// Use a local binary
let bin_path = PathBuf::from_str("/usr/local/bin/bitcoind").unwrap();
let bitcoind_beta = BitcoinD::from_bin(&bin_path).unwrap();
// Connect peers
connect(&bitcoind_alpha, &bitcoind_beta).unwrap()
// Mine blocks
bitcoind_alpha.generate(100).unwrap();
assert_eq!(bitcoind_alpha.get_height().unwrap(), 100);
// Wait for a node to catch up with the other
wait_for_height(&bitcoind_beta, 100).unwrap();
assert_eq!(bitcoind_beta.get_height().unwrap(), 100);
```
### UtreexoD
```rust
use halfin::utreexod::UtreexoD;
// Use a downloaded binary
let utreexod = UtreexoD::new().unwrap();
// Mine blocks
utreexod.generate(100).unwrap();
assert_eq!(utreexod.get_height().unwrap(), 100);
// Raw call an unimplemented RPC
let res = utreexod.call("uptime", &[]).unwrap();
```
## Running on CI environments
Since [`utreexod`](https://github.com/utreexo/utreexod) binaries are downloaded directly
from its GitHub releases page, we can get 403'ed by GitHub itself. To curb this, you need
to export the `GITHUB_TOKEN` environment variable and give `read` permissions in your CI
workflow, as such:
```yml
env:
GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
permissions:
contents: read
```
The [`build.rs`](./build.rs) script automatically reads this variable from the
environment and adds it as an `Authorization: Bearer $GITHUB_TOKEN` header
when making requests to `github.com`.
```rs
if let Ok(token) = env::var("GITHUB_TOKEN") {
request = request.with_header("Authorization", format!("Bearer {}", token));
}
```
## Developing
This project uses [`just`](https://github.com/casey/just) for command running, and
[`cargo-rbmt`](https://github.com/rust-bitcoin/rust-bitcoin-maintainer-tools/tree/master/cargo-rbmt)
to manage everything related to `cargo`, such as formatting, linting, testing and CI. To install them, run:
```console
~$ cargo install just
~$ cargo install cargo-rbmt
```
A `justfile` is provided for convenience. Run `just` to see available commands:
```console
~$ just
> halfin
> A regtest runner for `bitcoind` and `utreexod`
Available recipes:
build # Build `halfin` [alias: b]
check # Check code formatting, compilation, and linting [alias: c]
check-sigs # Checks whether all commits in this branch are signed [alias: cs]
delete-bins # Delete binaries under `target/bin/` [alias: db]
doc # Generate documentation [alias: d]
doc-open # Generate and open documentation [alias: do]
fmt # Format code [alias: f]
lock # Regenerate Cargo-recent.lock and Cargo-minimal.lock [alias: l]
pre-push # Run pre-push suite: lock, fmt, check, and test [alias: p]
test # Run tests across all toolchains and lockfiles [alias: t]
```
## Minimum Supported Rust Version
This library should compile with any combination of features on Rust 1.85.0.
To build with the MSRV toolchain, copy `Cargo-minimal.lock` to `Cargo.lock`.
## License
Licensed under either of
* Apache License, Version 2.0, ([LICENSE-APACHE](LICENSE-APACHE) or <https://www.apache.org/licenses/LICENSE-2.0>)
* MIT license ([LICENSE-MIT](LICENSE-MIT) or <https://opensource.org/licenses/MIT>)
at your option.
### Contribution
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.