The following JS code uses a basic BNB Smart Chain endpoint from QuickNode and ethers.js v6.3.0 to parse all transactions' data that is sent to PancakeSwap address.
const address = '0x18B2A687610328590Bc8F2e5fEdDe3b582A49cdA';
const interface = new ethers.Interface(abi);
provider.on("pending", async (tx) => {
const txInfo = await provider.getTransaction(tx);
if (txInfo !== null && txInfo['to'] === address) {
let decodedData = interface.parseTransaction({ data: txInfo.data });
However there are two issues related to the execution:
PancakeSwap. I have verified this by sending a transaction on my own to PancakeSwap address. My only guess is that this could be a premium feature of QuickNode which is not available in the basic free version.ethers.js interface does not always parse the transaction's data. In most cases, the execution of parseTransaction function returns null.Additionally, this is the ABI used to get the interface
const abi = 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ccount","type":"address"}],"name":"Unpaused","type":"event"},{"inputs":[],"name":"MAX_TREASURY_FEE","outputs":[{"internalType":"uint256","name":"","type":"uint256"}],"stateMutability":"view","type":"function"},{"inputs":[],"name":"adminAddress","outputs":[{"internalType":"address","name":"","type":"address"}],"stateMutability":"view","type":"function"},{"inputs":[{"internalType":"uint256","name":"epoch","type":"uint256"}],"name":"betBear","outputs":[],"stateMutability":"payable","type":"function"},{"inputs":[{"internalType":"uint256","name":"epoch","type":"uint256"}],"name":"betBull","outputs":[],"stateMutability":"payable","type":"function"},{"inputs":[],"name":"bufferSeconds","outputs":[{"internalType":"uint256","name":"","type":"uint256"}],"stateMutability":"view","type":"function"},{"inputs":[{"internalType":"uint256[]","name":"epochs","type":"uint256[]"}],"name":"claim","outputs":[],"stateMutability":"nonpayable","type":"function"},{"inputs":[],"name":"claimTreasury","outputs":[],"stateMutability":"nonpayable","type":"function"},{"inputs":[{"internalType":"uint256","name":"epoch","type":"uint256"},{"internalType":"address","name":"user","type":"address"}],"name":"claimable","outputs":[{"internalType":"bool","name":"","type":"bool"}],"stateMutability":"view","type":"function"},{"inputs":[],"name":"currentEpoch","outputs":[{"internalType":"uint256","name":"","type":"uint256"}],"stateMutability":"view","type":"function"},{"inputs":[],"name":"executeRound","outputs":[],"stateMutability":"nonpayable","type":"function"},{"inputs":[],"name":"genesisLockOnce","outputs":[{"internalType":"bool","name":"","type":"bool"}],"stateMutability":"view","type":"function"},{"inputs":[],"name":"genesisLockRound","outputs":[],"stateMutability":"nonpayable","type":"function"},{"inputs":[],"name":"genesisStartOnce","outputs":[{"internalType":"bool","name":"","type":"bool"}],"stateMutability":"view","type":"function"},{"inputs":[],"name":"genesisStartRound","outputs":[],"stateMutability":"nonpayable","type":"function"},{"inputs":[{"internalType":"address","name":"user","type":"address"},{"internalType":"uint256","name":"cursor","type":"uint256"},{"internalType":"uint256","name":"size","type":"uint256"}],"name":"getUserRounds","outputs":[{"internalType":"uint256[]","name":"","type":"uint256[]"},{"components":[{"internalType":"enum PancakePredictionV2.Position","name":"position","type":"uint8"},{"internalType":"uint256","name":"amount","type":"uint256"},{"internalType":"bool","name":"claimed","type":"bool"}],"internalType":"struct PancakePredictionV2.BetInfo[]","name":"","type":"tuple[]"},{"internalType":"uint256","name":"","type":"uint256"}],"stateMutability":"view","type":"function"},{"inputs":[{"internalType":"address","name":"user","type":"address"}],"name":"getUserRoundsLength","outputs":[{"internalType":"uint256","name":"","type":"uint256"}],"stateMutability":"view","type":"function"},{"inputs":[],"name":"intervalSeconds","outputs":[{"internalType":"uint256","name":"","type":"uint256"}],"stateMutability":"view","type":"function"},{"inputs":[{"internalType":"uint256","name":"","type":"uint256"},{"internalType":"address","name":"","type":"address"}],"name":"ledger","outputs":[{"internalType":"enum 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AggregatorV3Interface","name":"","type":"address"}],"stateMutability":"view","type":"function"},{"inputs":[],"name":"oracleLatestRoundId","outputs":[{"internalType":"uint256","name":"","type":"uint256"}],"stateMutability":"view","type":"function"},{"inputs":[],"name":"oracleUpdateAllowance","outputs":[{"internalType":"uint256","name":"","type":"uint256"}],"stateMutability":"view","type":"function"},{"inputs":[],"name":"owner","outputs":[{"internalType":"address","name":"","type":"address"}],"stateMutability":"view","type":"function"},{"inputs":[],"name":"pause","outputs":[],"stateMutability":"nonpayable","type":"function"},{"inputs":[],"name":"paused","outputs":[{"internalType":"bool","name":"","type":"bool"}],"stateMutability":"view","type":"function"},{"inputs":[{"internalType":"address","name":"_token","type":"address"},{"internalType":"uint256","name":"_amount","type":"uint256"}],"name":"recoverToken","outputs":[],"stateMutability":"nonpayable","type":"function"},{"inputs":[{"internalType":"uint256","name":"epoch","type":"uint256"},{"internalType":"address","name":"user","type":"address"}],"name":"refundable","outputs":[{"internalType":"bool","name":"","type":"bool"}],"stateMutability":"view","type":"function"},{"inputs":[],"name":"renounceOwnership","outputs":[],"stateMutability":"nonpayable","type":"function"},{"inputs":[{"internalType":"uint256","name":"","type":"uint256"}],"name":"rounds","outputs":[{"internalType":"uint256","name":"epoch","type":"uint256"},{"internalType":"uint256","name":"startTimestamp","type":"uint256"},{"internalType":"uint256","name":"lockTimestamp","type":"uint256"},{"internalType":"uint256","name":"closeTimestamp","type":"uint256"},{"internalType":"int256","name":"lockPrice","type":"int256"},{"internalType":"int256","name":"closePrice","type":"int256"},{"internalType":"uint256","name":"lockOracleId","type":"uint256"},{"internalType":"uint256","name":"closeOracleId","type":"uint256"},{"internalType":"uint256","name":"totalAmount","type":"uint256"},{"internalType":"uint256","name":"bullAmount","type":"uint256"},{"internalType":"uint256","name":"bearAmount","type":"uint256"},{"internalType":"uint256","name":"rewardBaseCalAmount","type":"uint256"},{"internalType":"uint256","name":"rewardAmount","type":"uint256"},{"internalType":"bool","name":"oracleCalled","type":"bool"}],"stateMutability":"view","type":"function"},{"inputs":[{"internalType":"address","name":"_adminAddress","type":"address"}],"name":"setAdmin","outputs":[],"stateMutability":"nonpayable","type":"function"},{"inputs":[{"internalType":"uint256","name":"_bufferSeconds","type":"uint256"},{"internalType":"uint256","name":"_intervalSeconds","type":"uint256"}],"name":"setBufferAndIntervalSeconds","outputs":[],"stateMutability":"nonpayable","type":"function"},{"inputs":[{"internalType":"uint256","name":"_minBetAmount","type":"uint256"}],"name":"setMinBetAmount","outputs":[],"stateMutability":"nonpayable","type":"function"},{"inputs":[{"internalType":"address","name":"_operatorAddress","type":"address"}],"name":"setOperator","outputs":[],"stateMutability":"nonpayable","type":"function"},{"inputs":[{"internalType":"address","name":"_oracle","type":"address"}],"name":"setOracle","outputs":[],"stateMutability":"nonpayable","type":"function"},{"inputs":[{"internalType":"uint256","name":"_oracleUpdateAllowance","type":"uint256"}],"name":"setOracleUpdateAllowance","outputs":[],"stateMutability":"nonpayable","type":"function"},{"inputs":[{"internalType":"uint256","name":"_treasuryFee","type":"uint256"}],"name":"setTreasuryFee","outputs":[],"stateMutability":"nonpayable","type":"function"},{"inputs":[{"internalType":"address","name":"newOwner","type":"address"}],"name":"transferOwnership","outputs":[],"stateMutability":"nonpayable","type":"function"},{"inputs":[],"name":"treasuryAmount","outputs":[{"internalType":"uint256","name":"","type":"uint256"}],"stateMutability":"view","type":"function"},{"inputs":[],"name":"treasuryFee","outputs":[{"internalType":"uint256","name":"","type":"uint256"}],"stateMutability":"view","type":"function"},{"inputs":[],"name":"unpause","outputs":[],"stateMutability":"nonpayable","type":"function"},{"inputs":[{"internalType":"address","name":"","type":"address"},{"internalType":"uint256","name":"","type":"uint256"}],"name":"userRounds","outputs":[{"internalType":"uint256","name":"","type":"uint256"}],"stateMutability":"view","type":"function"}]
Any directions would be greatly appreciated, thank you in advance.
The provider does not deliver all transactions to
PancakeSwap
provider.on("pending", async (tx) => {
The pending hook retrieves all transactions that the provider's node knows about before they're included in a block. If the node learns about the transaction as part of a new block (but not sooner), then the transaction is not included in the pending hook.
The EVM pending transaction propagation is designed in a way that the broadcasting node sends it to its neighbor nodes. Each of this neighbors check if it already knows this transaction. If the node doesn't know the transaction yet, the node saves the transaction in its local mempool (= database of pending transactions), and broadcasts to other neighbors, ...
But it's also possible that the transaction doesn't get to a node as part of the pending transaction propagation - but only as part of a new block. This is more likely on chains with fast block times where there's simply not enough time to propagate the pending transaction to all nodes in the network before it's already included in a block.
The
ethers.jsinterface does not always parse the transaction's data.
From the docs page:
If the matching function cannot be found, return null.
And from what I see in the parseTransaction source, one of the reasons why it might return null is when the function selector (first 4 bytes of the transaction data field) doesn't match any function in the ABI, when the parameter length doesn't match, or generally when ethers.js can't parse the transaction. It's hard to say without specific transaction example.