nautechsystems/nautilus_trader · error

Missing block number

Error message

Missing block number

What it means

transform_hypersync_block converts a hypersync_client Block into the domain Block. The error fires when the source block's number field is None — a block without a number cannot be mapped into the domain model, which keys blocks by height.

Source

Thrown at crates/adapters/blockchain/src/hypersync/transform.rs:33

use alloy::primitives::U256;
use hypersync_client::format::Hex;
use nautilus_core::{UnixNanos, datetime::NANOSECONDS_IN_SECOND};
use nautilus_model::defi::{Block, Blockchain, hex::from_str_hex_to_u64};
use ustr::Ustr;

/// Converts a HyperSync block format to our internal [`Block`] type.
///
/// # Errors
///
/// Returns an error if required block fields are missing or if hex parsing fails.
pub fn transform_hypersync_block(
    chain: Blockchain,
    received_block: hypersync_client::simple_types::Block,
) -> Result<Block, anyhow::Error> {
    let number = received_block
        .number
        .ok_or_else(|| anyhow::anyhow!("Missing block number"))?;
    let gas_limit = from_str_hex_to_u64(
        received_block
            .gas_limit
            .ok_or_else(|| anyhow::anyhow!("Missing gas limit"))?
            .encode_hex()
            .as_str(),
    )?;
    let gas_used = from_str_hex_to_u64(
        received_block
            .gas_used
            .ok_or_else(|| anyhow::anyhow!("Missing gas used"))?
            .encode_hex()
            .as_str(),
    )?;
    let timestamp = from_str_hex_to_u64(
        received_block
            .timestamp
            .ok_or_else(|| anyhow::anyhow!("Missing timestamp"))?

View on GitHub (pinned to 18893faf8b)

Solutions

1. Verify the HyperSync request selects the block number field
2. Skip blocks with number == None and re-fetch them
3. Check/update hypersync-client version for schema regressions
4. Log the raw response to diagnose upstream data gaps

Example fix

// before
let number = received_block.number.ok_or_else(|| anyhow::anyhow!("Missing block number"))?;
// after
let Some(number) = received_block.number else {
    tracing::warn!("hypersync block missing number; skipping block");
    return Ok(None);
};

if received_block.number.is_none() {
    tracing::warn!("skipping hypersync block without number");
    return Ok(None);
}

fn block_has_number(b: &hypersync_client::simple_types::Block) -> bool {
    b.number.is_some()
}

match transform_hypersync_block(chain, block) {
    Ok(b) => /* use b */,
    Err(e) => { tracing::warn!("block transform failed: {e}"); continue; }
}

When it happens

Trigger: pool_events_from_response receives a HyperSync response whose block object has number == None and passes it to transform_hypersync_block.

Common situations: Partial or malformed HyperSync responses; upstream API/schema changes; synthetic test blocks lacking a number; version mismatch between hypersync-client and expected schema.

Understand the failure class

Background: "missing required argument" and "the following required arguments were not provided": what required-argument errors mean and how to fix them — this error's family across 20 libraries.

Related errors

• Missing gas limit
• Missing transaction hash in log
• Missing transaction index in the log
• Missing log index in the log
• Missing block number in the log

AI-assisted analysis of nautechsystems/nautilus_trader@18893faf8b (2026-09-08). Data as JSON: /api/errors/e99be5f58e94aed8. Report an issue: GitHub.