nautechsystems/nautilus_trader · error

Burn event data is too short

Error message

Burn event data is too short

What it means

Raised by parse_burn_event_hypersync when the Burn event's data section contains fewer than 96 bytes (3 x 32). A Uniswap V3 Burn event encodes amount, txgBalance0 and txgBalance1 (amount0, amount1) as three 32-byte words in data. If the data is shorter the ABI layout cannot be honored, so the parser rejects the log rather than decoding garbage.

Source

Thrown at crates/adapters/blockchain/src/exchanges/parsing/uniswap_v3/burn.rs:83

        }
        None => anyhow::bail!("Missing tickLower in topic2 when parsing burn event"),
    };

    // Extract int24 tickUpper from topic3 (stored as a 32-byte padded value)
    let tick_upper = match log.topics.get(3).and_then(|t| t.as_ref()) {
        Some(topic) => {
            let tick_upper_bytes: [u8; 32] = topic.as_ref().try_into()?;
            i32::from_be_bytes(tick_upper_bytes[28..32].try_into()?)
        }
        None => anyhow::bail!("Missing tickUpper in topic3 when parsing burn event"),
    };

    if let Some(data) = &log.data {
        let data_bytes = data.as_ref();

        // Validate if data contains 3 parameters of 32 bytes each
        if data_bytes.len() < 3 * 32 {
            anyhow::bail!("Burn event data is too short");
        }

        // Decode the data using the BurnEventData struct
        let decoded = match <BurnEventData as SolType>::abi_decode(data_bytes) {
            Ok(decoded) => decoded,
            Err(e) => anyhow::bail!("Failed to decode burn event data: {e}"),
        };

        let pool_address = Address::from_slice(
            log.address
                .clone()
                .expect("Contract address should be set in logs")
                .as_ref(),
        );
        let pool_identifier = PoolIdentifier::Address(Ustr::from(&pool_address.to_string()));
        Ok(BurnEvent::new(
            dex,
            pool_identifier,

View on GitHub (pinned to 18893faf8b)

Solutions

1. Confirm the topic0 filter targets exactly the Uniswap V3 Burn event signature so only genuine Burn logs reach the parser
2. Pre-validate log.data length before calling the parser and skip/log logs with fewer than 96 data bytes
3. Inspect the raw log (data hex length) for the failing transaction on a block explorer to see what event was actually emitted
4. Fix the test fixture so the data hex string encodes three full 32-byte words (64+96 hex chars / 0x + 192 hex chars)

Example fix

// before
if let Some(data) = &log.data {
    let data_bytes = data.as_ref();
    if data_bytes.len() < 3 * 32 { anyhow::bail!("Burn event data is too short"); }
// after (caller-side)
if log.data.as_ref().map(|d| d.len()).unwrap_or(0) < 96 {
    tracing::warn!("skipping log with insufficient Burn event data");
    return Ok(None);
}
parse_burn_event_hypersync(log)?;

fn burn_data_ok(log: &HyperSyncLog) -> bool {
    log.data.as_ref().map(|d| d.len() >= 96).unwrap_or(false)
}
// call parse_burn_event_hypersync only if burn_data_ok(&log)

match parse_burn_event_hypersync(&log) {
    Ok(ev) => handle(ev),
    Err(e) if e.to_string().contains("Burn event data is too short") => {
        tracing::warn!("short burn data; skipping log");
    }
    Err(e) => return Err(e.into()),
}

When it happens

Trigger: Calling parse_burn_event_hypersync with a HyperSync log whose data field is missing, empty, or truncated to fewer than 96 bytes — e.g. a non-Burn event matched by a loose topic0 filter, or a fixture with partial data.

Common situations: Broad subscription filters capturing other events with 4 topics; malformed/truncated log payloads from a HyperSync response; test fixtures with hex data strings that are too short (e.g. only one 32-byte word); an empty string data field decoded to zero bytes.

Understand the failure class

Background: Schema validation failed / invalid input schema: payload rejected because its shape doesn't match the expected schema — this error's family across 28 libraries.

Related errors

• Missing tickUpper in topic3 when parsing burn event
• Finalized transaction {} emitted {} Swap logs; expected exac
• Missing tickLower in topic2 when parsing burn event
• Failed to decode burn event data: {e}
• Missing tickLower in topic2 when parsing collect event

AI-assisted analysis of nautechsystems/nautilus_trader@18893faf8b (2026-09-08). Data as JSON: /api/errors/b5b0cdb3f3cae6ae. Report an issue: GitHub.