Mithril client library

info

Mithril client library can be used by Rust developers to use the Mithril network in their applications.

It is responsible for handling the different types of data certified by Mithril and available through a Mithril aggregator:

• Snapshot: list, get, download the tarball, and record statistics
• Mithril stake distribution: list and get
• Cardano transaction: list and get snapshots, get proofs
• Cardano stake distribution: list, get, and get by epoch
• Certificate: list, get, and chain validation.

tip

• For more information about the Mithril network, please see the architecture overview

• For more information about the Mithril client node, please see this overview

• Check out the Bootstrap a Cardano node guide.

info

The Mithril network configurations are available in the Network configurations section of the user manual.

Resources

Node	Source repository	Rust documentation	Network configurations
Mithril client	↗️	↗️	↗️

Prerequisites

• Install the latest stable version of the correctly configured Rust toolchain

• Install build tools build-essential and m4; for example, on Ubuntu/Debian/Mint, run sudo apt install build-essential m4

• Install OpenSSL development libraries; for example, on Ubuntu/Debian/Mint, run apt install libssl-dev.

Installation

In your project, use cargo to add mithril-client crate as a dependency:

cargo add mithril-client

info

Mithril client is an asynchronous library. You will need a runtime to execute your futures. We recommend using the crate tokio, as the library has been tested with it.

Using the Mithril client library

Below is a basic example of how to use most of the functions exposed by the Mithril client library:

/src/main.rs

use mithril_client::{ClientBuilder, MessageBuilder};
use std::path::Path;

#[tokio::main]
async fn main() -> mithril_client::MithrilResult<()> {
    let client = ClientBuilder::aggregator("YOUR_AGGREGATOR_ENDPOINT", "YOUR_GENESIS_VERIFICATION_KEY").build()?;

    let snapshots = client.snapshot().list().await?;

    let last_digest = snapshots.first().unwrap().digest.as_ref();
    let snapshot = client.snapshot().get(last_digest).await?.unwrap();

    let certificate = client
        .certificate()
        .verify_chain(&snapshot.certificate_hash)
        .await?;

    // Note: the directory must already exist, and the user running this code must have read/write access to it.
    let target_directory = Path::new("YOUR_TARGET_DIRECTORY");
    client
        .snapshot()
        .download_unpack(&snapshot, target_directory)
        .await?;

    if let Err(e) = client.snapshot().add_statistics(&snapshot).await {
        println!("Could not increment snapshot download statistics: {:?}", e);
    }

    let message = MessageBuilder::new()
        .compute_snapshot_message(&certificate, target_directory)
        .await?;
    assert!(certificate.match_message(&message));

    Ok(())
}

info

Snapshot download and certificate chain validation can take quite some time, even with a fast computer and network. We have implemented a feedback mechanism for them; more details are available in the feedback sub-module.

An example of implementation with the crate indicatif is available in the Mithril repository. To run it, execute the following command:

cargo run -p client-snapshot

or directly from the example crate directory:

cargo run

Here is a working example of the code using the configuration parameters of the release-preprod network:

/src/main.rs

use mithril_client::{ClientBuilder, MessageBuilder};
use std::path::Path;

#[tokio::main]
async fn main() -> mithril_client::MithrilResult<()> {
    let client = ClientBuilder::aggregator("https://aggregator.release-preprod.api.mithril.network/aggregator", "5b3132372c37332c3132342c3136312c362c3133372c3133312c3231332c3230372c3131372c3139382c38352c3137362c3139392c3136322c3234312c36382c3132332c3131392c3134352c31332c3233322c3234332c34392c3232392c322c3234392c3230352c3230352c33392c3233352c34345d").build()?;

    let snapshots = client.snapshot().list().await?;

    let last_digest = snapshots.first().unwrap().digest.as_ref();
    let snapshot = client.snapshot().get(last_digest).await?.unwrap();

    let certificate = client
        .certificate()
        .verify_chain(&snapshot.certificate_hash)
        .await?;

    // Note: the directory must already exist, and the user running this code must have read/write access to it.
    let target_directory = Path::new(".");
    client
        .snapshot()
        .download_unpack(&snapshot, target_directory)
        .await?;

    if let Err(e) = client.snapshot().add_statistics(&snapshot).await {
        println!("Could not increment snapshot download statistics: {:?}", e);
    }

    let message = MessageBuilder::new()
        .compute_snapshot_message(&certificate, target_directory)
        .await?;
    assert!(certificate.match_message(&message));

    Ok(())
}

tip

You can read the complete developer documentation.