ethers-rs/ethers-middleware/src/gas_oracle/etherscan.rs

52 lines
1.8 KiB
Rust

use async_trait::async_trait;
use ethers_core::types::U256;
use ethers_etherscan::Client;
use crate::gas_oracle::{GasCategory, GasOracle, GasOracleError, GWEI_TO_WEI};
/// A client over HTTP for the [Etherscan](https://api.etherscan.io/api?module=gastracker&action=gasoracle) gas tracker API
/// that implements the `GasOracle` trait
#[derive(Clone, Debug)]
pub struct Etherscan {
client: Client,
gas_category: GasCategory,
}
impl Etherscan {
/// Creates a new [Etherscan](https://etherscan.io/gastracker) gas price oracle.
pub fn new(client: Client) -> Self {
Etherscan { client, gas_category: GasCategory::Standard }
}
/// Sets the gas price category to be used when fetching the gas price.
#[must_use]
pub fn category(mut self, gas_category: GasCategory) -> Self {
self.gas_category = gas_category;
self
}
}
#[cfg_attr(target_arch = "wasm32", async_trait(?Send))]
#[cfg_attr(not(target_arch = "wasm32"), async_trait)]
impl GasOracle for Etherscan {
async fn fetch(&self) -> Result<U256, GasOracleError> {
if matches!(self.gas_category, GasCategory::Fastest) {
return Err(GasOracleError::GasCategoryNotSupported)
}
let result = self.client.gas_oracle().await?;
match self.gas_category {
GasCategory::SafeLow => Ok(U256::from(result.safe_gas_price * GWEI_TO_WEI)),
GasCategory::Standard => Ok(U256::from(result.propose_gas_price * GWEI_TO_WEI)),
GasCategory::Fast => Ok(U256::from(result.fast_gas_price * GWEI_TO_WEI)),
_ => Err(GasOracleError::GasCategoryNotSupported),
}
}
async fn estimate_eip1559_fees(&self) -> Result<(U256, U256), GasOracleError> {
Err(GasOracleError::Eip1559EstimationNotSupported)
}
}