ethers-rs/examples/subscriptions/examples/subscribe_events_by_type.rs

51 lines
1.6 KiB
Rust

use ethers::{
contract::{abigen, Contract},
core::types::ValueOrArray,
providers::{Provider, StreamExt, Ws},
};
use std::{error::Error, sync::Arc};
abigen!(
AggregatorInterface,
r#"[
event AnswerUpdated(int256 indexed current, uint256 indexed roundId, uint256 updatedAt)
]"#,
);
const PRICE_FEED_1: &str = "0x7de93682b9b5d80d45cd371f7a14f74d49b0914c";
const PRICE_FEED_2: &str = "0x0f00392fcb466c0e4e4310d81b941e07b4d5a079";
const PRICE_FEED_3: &str = "0xebf67ab8cff336d3f609127e8bbf8bd6dd93cd81";
/// Subscribe to a typed event stream without requiring a `Contract` instance.
/// In this example we subscribe Chainlink price feeds and filter out them
/// by address.
#[tokio::main]
async fn main() -> Result<(), Box<dyn Error>> {
let client = get_client().await;
let client = Arc::new(client);
// Build an Event by type. We are not tied to a contract instance. We use builder functions to
// refine the event filter
let event = Contract::event_of_type::<AnswerUpdatedFilter>(client)
.from_block(16022082)
.address(ValueOrArray::Array(vec![
PRICE_FEED_1.parse()?,
PRICE_FEED_2.parse()?,
PRICE_FEED_3.parse()?,
]));
let mut stream = event.subscribe_with_meta().await?.take(2);
// Note that `log` has type AnswerUpdatedFilter
while let Some(Ok((log, meta))) = stream.next().await {
println!("{log:?}");
println!("{meta:?}")
}
Ok(())
}
async fn get_client() -> Provider<Ws> {
Provider::<Ws>::connect("wss://eth.llamarpc.com").await.unwrap()
}