ERC20 Approvals

use futures::StreamExt;
use std::{collections::HashSet, sync::Arc};
use pangea_client::{
    core::types::ChainId, query::Bound,
    ClientBuilder, Format, WsProvider,
    provider::Erc20Provider, requests::erc20::GetErc20ApprovalsRequest, 
};
 
#[tokio::main]
async fn main() {
    dotenvy::dotenv_override().ok();
 
    let client = match ClientBuilder::default()
        .endpoint("app.pangea.foundation")
        .build::<WsProvider>()
        .await
    {
        Ok(client) => Arc::new(client),
        Err(e) => {
            eprintln!("Client failed to initialize:\n{e}");
            return;
        }
    };
 
    {
        let request = GetErc20ApprovalsRequest { 
            chains: HashSet::from([ChainId::ETH]), 
            from_block: Bound::Exact(21000000), 
            to_block: Bound::Exact(21010000), 
            address__in: HashSet::from(["0x2260fac5e5542a773aa44fbcfedf7c193bc2c599"
            .parse() 
            .unwrap()]), 
            ..Default::default() 
        }; 
        let stream = match client 
            .get_erc20_approval_by_format(request, Format::JsonStream, false) 
            .await
        {
            Ok(stream) => stream,
            Err(e) => {
                eprintln!("Request failed\n{e}");
                return;
            }
        };
 
        futures::pin_mut!(stream);
 
        while let Some(chunk) = stream.next().await {
            let chunk = String::from_utf8(chunk.unwrap()).unwrap();
            println!("{chunk}");
        }
    }
}