cannot get earlier transactions and blocks about helios HOT 8 OPEN

Oh I see what is happening here. Helios only stores block data for blocks that start either after helios starts or within 64 blocks of the current block number (whichever is higher).

This is mostly a limitation due to efficiency as well as how the light client protocol works.

from helios.

Can you please provide the full code example so I can help you debug?

from helios.

sure, there's the whole function:

#[tokio::main]
async fn main() -> Result<()> {
    dotenv().ok();
    set_logger();

    let network = Network::GOERLI;
    let cf = checkpoints::CheckpointFallback::new()
        .build()
        .await
        .unwrap();
    info!("Checkpoint fallback services built");

    let checkpoint = cf.fetch_latest_checkpoint(&network).await.unwrap();
    let checkpoint = format!("{:?}", checkpoint);

    let execution_rpc_url = get_env_variable("EXECUTION_RPC")?;
    let consensus_rpc_url = get_env_variable("CONSENSUS_RPC")?;

    let mut client: Client<FileDB> = ClientBuilder::new()
        .network(network)
        .execution_rpc(&execution_rpc_url)
        .consensus_rpc(&consensus_rpc_url)
        .load_external_fallback()
        .checkpoint(&checkpoint)
        .data_dir("/tmp/helios".parse()?)
        .build()?;
    info!("client created");

    client.start().await?;
    client.wait_synced().await;

    let block_number: u64 = 19075597;

    let block = client
        .get_block_by_number(BlockTag::Number(block_number), true)
        .await?;
    info!("block: {:?}", block);
    Ok(())
}

from helios.

@ncitron first, thanks for your help!

I have a similar problem now but with transactions.
I use the get_transaction_receipt function in order to get the receipt of a transaction that is created after the start of the client, but I keep getting a None result for some reason.

I inject the hash of the transaction to the tx_hash_str variable using a breakpoint, and i am taking a transaction hash from etherscan explorer.
I tried both pending transactions and approved transactions, but both gives the same result of None, when the transaction is clearly created after the client.
I use the same code as above, but with changing the block fetching part with the following:

	let tx_hash_str = "";
	//here i use a breakpoint and put the hash string into tx_hash_str
    let tx_hash = H256::from_str(tx_hash_str).unwrap();
    let tx = client
        .get_transaction_receipt(&tx_hash)
        .await?;

from helios.

Can you confirm that you can fetch a block for the block number of the transaction?

from helios.

Yes, I can do this.

from helios.

Hmm it seems I am able to fetch a receipt using this simple example:

client.start().await?;
client.wait_synced().await;

let head_block_num = client.get_block_number().await?;
let head_block = client.get_block_by_number(BlockTag::Number(head_block_num.as_u64()), false).await;
let tx_hash = head_block.unwrap().unwrap().transactions.hashes()[0];
let receipt = client.get_transaction_receipt(&tx_hash).await.unwrap().unwrap();
println!("{:?}", receipt);

I wonder if the breakpoints are causing it to act up. If helios can fetch the block it should always be able to get a receipt from within that block.

from helios.

Thanks for all the help!
It seems I did not understand the light client's logics just right. I now understand that I would be able to fetch only transactions from already fetched blocks.

from helios.