mithril_aggregator/tools/
era.rs

use std::path::{Path, PathBuf};

use anyhow::anyhow;
use mithril_common::{
    chain_observer::{TxDatumBuilder, TxDatumFieldValue},
    crypto_helper::EraMarkersSigner,
    entities::Epoch,
    era::{adapters::EraMarkersPayloadCardanoChain, EraMarker, SupportedEra},
    StdResult,
};

type EraToolsResult<R> = StdResult<R>;

pub struct EraTools {}

impl EraTools {
    pub fn new() -> Self {
        Self {}
    }

    /// Get list of supported eras
    pub fn get_supported_eras_list(&self) -> EraToolsResult<Vec<SupportedEra>> {
        Ok(SupportedEra::eras())
    }

    /// Generate TxDatum for eras with sanity check of epochs
    pub fn generate_tx_datum(
        &self,
        current_era_epoch: Epoch,
        maybe_next_era_epoch: Option<Epoch>,
        era_markers_signer: &EraMarkersSigner,
    ) -> EraToolsResult<String> {
        if maybe_next_era_epoch.is_some()
            && maybe_next_era_epoch.unwrap_or_default() <= current_era_epoch
        {
            Err(anyhow!(
                "next era epoch must be strictly greater than the current era epoch"
            ))?;
        }

        let mut era_markers = Vec::new();
        for (index, era) in SupportedEra::eras().iter().enumerate() {
            let era_marker = match index {
                0 => EraMarker::new(&era.to_string(), Some(current_era_epoch)),
                1 => EraMarker::new(&era.to_string(), maybe_next_era_epoch),
                _ => Err(anyhow!("too many eras retrieved, can't generate tx datum"))?,
            };
            era_markers.push(era_marker);
        }
        let era_markers_payload = EraMarkersPayloadCardanoChain {
            markers: era_markers,
            signature: None,
        }
        .sign(era_markers_signer)?;

        let tx_datum = TxDatumBuilder::new()
            .add_field(TxDatumFieldValue::Bytes(era_markers_payload.to_json_hex()?))
            .build()?;
        Ok(tx_datum.0)
    }

    /// Export the era keypair to a folder and returns the paths to the files (secret key, verification_key)
    pub fn create_and_save_era_keypair(keypair_path: &Path) -> StdResult<(PathBuf, PathBuf)> {
        let era_signer = EraMarkersSigner::create_non_deterministic_signer();
        let era_secret_key_path = keypair_path.join("era.sk");
        era_signer
            .secret_key()
            .write_json_hex_to_file(&era_secret_key_path)?;
        let era_verification_key_path = keypair_path.join("era.vk");
        era_signer
            .verification_key()
            .write_json_hex_to_file(&era_verification_key_path)?;

        Ok((era_secret_key_path, era_verification_key_path))
    }
}

#[cfg(test)]
mod tests {
    use mithril_common::{
        crypto_helper::{EraMarkersVerifierSecretKey, EraMarkersVerifierVerificationKey},
        test_utils::TempDir,
    };
    use std::fs::read_to_string;

    use super::*;

    fn build_tools() -> EraTools {
        EraTools {}
    }

    fn get_temp_dir(dir_name: &str) -> PathBuf {
        TempDir::create("era", dir_name)
    }

    #[test]
    fn get_supported_eras_list() {
        let era_tools = build_tools();
        let supported_eras_list = era_tools
            .get_supported_eras_list()
            .expect("get_supported_eras_list should not fail");
        assert_eq!(supported_eras_list, SupportedEra::eras());
    }

    #[test]
    fn generate_tx_datum_ok() {
        let era_markers_signer = EraMarkersSigner::create_deterministic_signer();
        let era_tools = build_tools();
        let _ = era_tools
            .generate_tx_datum(Epoch(1), None, &era_markers_signer)
            .expect("generate_tx_datum should not fail");
    }

    #[test]
    fn generate_tx_datum_wrong_epochs() {
        let era_markers_signer = EraMarkersSigner::create_deterministic_signer();
        let era_tools = build_tools();
        let _ = era_tools
            .generate_tx_datum(Epoch(3), Some(Epoch(2)), &era_markers_signer)
            .expect_err("generate_tx_datum should have failed");
    }

    #[test]
    fn test_create_and_save_era_keypair() {
        let temp_dir = get_temp_dir("test_create_and_save_era_keypair");
        let (era_secret_key_path, era_verification_key_path) =
            EraTools::create_and_save_era_keypair(&temp_dir)
                .expect("Failed to create and save era keypair");
        let era_secret_key = EraMarkersVerifierSecretKey::from_json_hex(
            &read_to_string(&era_secret_key_path).expect("Failed to read era secret key file"),
        )
        .expect("Failed to parse era secret key");
        let era_verification_key = EraMarkersVerifierVerificationKey::from_json_hex(
            &read_to_string(&era_verification_key_path)
                .expect("Failed to read era verification key file"),
        )
        .expect("Failed to parse era verification key");
        let era_verifier = EraMarkersSigner::from_secret_key(era_secret_key).create_verifier();

        let expected_era_verification_key = era_verifier.to_verification_key();
        assert_eq!(expected_era_verification_key, era_verification_key);
    }
}
mithril_aggregator/tools/era.rs

mithril_aggregator/tools/
era.rs
