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ethereum

Is there an API for ethereum address monitoring? Or how to get notifications when an address is paided

Consider the simple scenario: some address transfers 100 usdt to address A; is there a method or api to watch on address A to get automated notifications? What is the best practice for these payin notifications of many (~100+) addresses?

Solution

  • You can subscribe to Transfer event logs emitted by the USDT contract. As defined in the ERC-20 standard, the second param of the event log is the recipient address.

    Example using web3js:

    const options = {
    address: "0xdAC17F958D2ee523a2206206994597C13D831ec7", // USDT contract on Ethereum
    topics: [
        web3.utils.keccak256("Transfer(address,address,uint256)"), // hash of the event definition
        null, // any sender
        ["0xFFfFfFffFFfffFFfFFfFFFFFffFFFffffFfFFFfF"] // recipient addresses
    ]
};

web3.eth.subscribe("logs", options, (err, data) => {
    console.log(data);
});