nautechsystems/nautilus_trader · error

SetFeeProtocol event data is too short

Error message

SetFeeProtocol event data is too short

What it means

Thrown by parse_fee_protocol_update_event_hypersync when the hypersync log's data field is present but shorter than the 4 x 32 = 128 bytes required to hold the SetFeeProtocol event's four padded parameters (feeProtocol0Old, feeProtocol1Old, feeProtocol0New, feeProtocol1New). The library checks length before decoding to avoid a guaranteed decode failure.

Source

Thrown at crates/adapters/blockchain/src/exchanges/parsing/uniswap_v3/fee_protocol_update.rs:71

/// # Panics
///
/// Panics if the contract address is not set in the log.
pub fn parse_fee_protocol_update_event_hypersync(
    dex: SharedDex,
    log: &HypersyncLog,
) -> anyhow::Result<FeeProtocolUpdateEvent> {
    validate_event_signature_hash(
        "SetFeeProtocolEvent",
        FEE_PROTOCOL_UPDATE_EVENT_SIGNATURE_HASH,
        log,
    )?;

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

        // Validate the data contains 4 parameters of 32 bytes each
        if data_bytes.len() < 4 * 32 {
            anyhow::bail!("SetFeeProtocol event data is too short");
        }

        let decoded = match <SetFeeProtocolEventData as SolType>::abi_decode(data_bytes) {
            Ok(decoded) => decoded,
            Err(e) => anyhow::bail!("Failed to decode SetFeeProtocol 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(FeeProtocolUpdateEvent::new(
            dex,
            pool_identifier,

View on GitHub (pinned to 18893faf8b)

Solutions

1. Ensure the hypersync query filters on the SetFeeProtocol topic0 signature so only matching event logs are fetched.
2. Check that log.data is populated and its hex is >= 256 hex chars (128 bytes).
3. Confirm the log comes from a standard Uniswap V3 pool; a SetFeeProtocol variant with different parameter layout will fail.
4. Fix test/log fixtures so data contains four 32-byte words.
5. If the event genuinely emits fewer words, update SetFeeProtocolEventData to the actual ABI and adjust the length check.

Example fix

// before
if data_bytes.len() < 4 * 32 {
    anyhow::bail!("SetFeeProtocol event data is too short");
}
// after
if data_bytes.len() != 4 * 32 {
    anyhow::bail!("SetFeeProtocol event data must be exactly 128 bytes, got {}", data_bytes.len());
}

fn is_valid_set_fee_protocol_data(data: Option<&[u8]>) -> bool {
    data.map(|d| d.len() == 4 * 32).unwrap_or(false)
}

fn has_set_fee_protocol_shape(log: &HypersyncLog) -> bool {
    log.data
        .as_ref()
        .map(|d| d.len() >= 128)
        .unwrap_or(false)
}

match parse_fee_protocol_update_event_hypersync(dex, &log) {
    Ok(event) => handle(event),
    Err(e) if e.to_string().contains("SetFeeProtocol") => {
        tracing::warn!("skipping invalid SetFeeProtocol log: {e}");
    }
    Err(e) => return Err(e),
}

When it happens

Trigger: A hypersync log whose topic0 matches SetFeeProtocol arrives with data shorter than 128 bytes — e.g. empty data, truncated hex, or data from a different event with fewer parameters.

Common situations: Feeding logs filtered only by address rather than by event topic so unrelated events slip through; hypersync query returning partial data fields; malformed/custom test fixtures in tests like test_parse_fee_protocol_update_event_hypersync.

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

• Failed to decode SetFeeProtocol event data: {e}
• Flash event data is too short
• Failed to decode flash event data: {e}
• Missing tickLower in topic2 when parsing burn event
• Missing data in SetFeeProtocol event log

AI-assisted analysis of nautechsystems/nautilus_trader@18893faf8b (2026-09-08). Data as JSON: /api/errors/417df1566f6ce2bb. Report an issue: GitHub.