{"record":{"id":"7edc7deecc32966c","repo":"nautechsystems/nautilus_trader","slug":"failed-to-decode-mint-event-data-e","errorCode":null,"errorMessage":"Failed to decode mint event data: {e}","messagePattern":"Failed to decode mint event data: (.+?)","errorType":"error_code","errorClass":null,"httpStatus":null,"severity":"error","filePath":"crates/adapters/blockchain/src/exchanges/parsing/uniswap_v3/mint.rs","lineNumber":90,"sourceCode":"        Some(topic) => {\n            let tick_upper_bytes: [u8; 32] = topic.as_ref().try_into()?;\n            i32::from_be_bytes(tick_upper_bytes[28..32].try_into()?)\n        }\n        None => anyhow::bail!(\"Missing tickUpper in topic3 when parsing mint event\"),\n    };\n\n    if let Some(data) = &log.data {\n        let data_bytes = data.as_ref();\n\n        // Validate if data contains 4 parameters of 32 bytes each\n        if data_bytes.len() < 4 * 32 {\n            anyhow::bail!(\"Mint event data is too short\");\n        }\n\n        // Decode the data using the MintEventData struct\n        let decoded = match <MintEventData as SolType>::abi_decode(data_bytes) {\n            Ok(decoded) => decoded,\n            Err(e) => anyhow::bail!(\"Failed to decode mint event data: {e}\"),\n        };\n\n        let pool_address = Address::from_slice(\n            log.address\n                .clone()\n                .expect(\"Contract address should be set in logs\")\n                .as_ref(),\n        );\n        let pool_identifier = PoolIdentifier::Address(Ustr::from(&pool_address.to_string()));\n        Ok(MintEvent::new(\n            dex,\n            pool_identifier,\n            extract_block_number(log)?,\n            extract_transaction_hash(log)?,\n            extract_transaction_index(log)?,\n            extract_log_index(log)?,\n            decoded.sender,\n            owner,","sourceCodeStart":72,"sourceCodeEnd":108,"githubUrl":"https://github.com/nautechsystems/nautilus_trader/blob/18893faf8b356be3320add8de2f861b0b647cf06/crates/adapters/blockchain/src/exchanges/parsing/uniswap_v3/mint.rs#L72-L108","documentation":"Thrown by parse_mint_event_hypersync when the data payload passes the 128-byte length check but alloy's abi_decode into MintEventData fails, with the underlying error embedded. Indicates the data words do not fit the expected Mint event layout (e.g. wrong word count, dynamic tails, or non-multiple-of-32 length).","triggerScenarios":"Hypersync log data >= 128 bytes but not exactly four static words — extra trailing bytes, dynamic encoding, or data belonging to a different event with the same topic0.","commonSituations":"Forked V3 Mint events with modified parameters, corrupted payloads, mixing logs across event types with colliding signatures.","solutions":["Require data_bytes.len() == 4 * 32 exactly rather than >= .","Manually decode the four words to inspect the layout against MintEventData.","Verify the pool contract is a standard Uniswap V3 deployment.","Check alloy-sol-types codegen matches the deployed Mint event ABI."],"exampleFix":"// before\nif data_bytes.len() < 4 * 32 { bail!(\"too short\"); }\nlet decoded = <MintEventData as SolType>::abi_decode(data_bytes)?;\n// after\nif data_bytes.len() != 4 * 32 {\n    anyhow::bail!(\"Mint data must be 128 bytes, got {}\", data_bytes.len());\n}\nlet decoded = <MintEventData as SolType>::abi_decode(data_bytes)?;","handlingStrategy":"validation","validationCode":"fn exact_mint_data(log: &HypersyncLog) -> bool {\n    log.data.as_ref().map(|d| d.len() == 128).unwrap_or(false)\n}\nif !exact_mint_data(&log) { skip(&log); }","typeGuard":"fn mint_data_words(log: &HypersyncLog) -> Option<&[u8; 128]> {\n    let d = log.data.as_deref()?;\n    (d.len() == 128).then_some(d.try_into().ok()?)\n}","tryCatchPattern":"match parse_mint_event_hypersync(log, dex) {\n    Ok(event) => process(event),\n    Err(e) if e.to_string().contains(\"Failed to decode mint event data\") => {\n        log::warn!(\"non-canonical mint payload: {e}\");\n    }\n    Err(e) => return Err(e),\n}","preventionTips":["Require exactly 128 bytes rather than >= 128","Manually decode the four words when debugging layout mismatches","Confirm the pool contract is a standard V3 deployment","Keep alloy-sol-types aligned with the deployed Mint ABI"],"tags":["abi-decode","uniswap-v3","hypersync","events"],"backgroundTag":"schema-validation-failed","analyzedSha":"18893faf8b356be3320add8de2f861b0b647cf06","analyzedAt":"2026-09-08T20:49:34.690Z","contentChangedAt":"2026-09-08T20:49:34.690Z","schemaVersion":2},"datasetVersion":"2026-09-14T00:17:10.932Z"}