从事务哈希检索erc20和erc721传输信息

Question

我想从事务哈希中检索以下信息：

• 如果该交易是ERC-20转让:如果是，什么erc20被转移了，金额是多少，转移给谁？
• 如果该交易是ERC-721传输:如果是，则erc721 nft被转移到谁？

示例：https://blockscout.com/xdai/mainnet/tx/0x5f1ac5db6c0c31025ac19f6de22eef665e57262f9953567438827b339828e1a8/token-transfers

我已经为这笔交易转了一些钱。现在我想从我的tx散列中检索上面的信息。

这就是我正在做的事情(使用ethers.js)：

        let blockchain = await Blockchain.findBy('network', 'xdai')
        let defaultProvider = await Ethers.getDefaultProvider(blockchain)

        let tx = await defaultProvider.getTransaction("0x5f1ac5db6c0c31025ac19f6de22eef665e57262f9953567438827b339828e1a8")
        let txReceipt = await defaultProvider.getTransactionReceipt("0x5f1ac5db6c0c31025ac19f6de22eef665e57262f9953567438827b339828e1a8")

结果：

{
    "tx": {
        "hash": "0x5f1ac5db6c0c31025ac19f6de22eef665e57262f9953567438827b339828e1a8",
        "blockHash": "0x4023d17a5469c9dfb13bf50a63ce40d90b07a4b8e811fdba25b063ad535ba3f2",
        "blockNumber": 21105871,
        "transactionIndex": 4,
        "confirmations": 151,
        "from": "0x52eB606f94091A2BA4f985D98C62880a9BA591B6",
        "gasPrice": {
            "type": "BigNumber",
            "hex": "0x59682f07"
        },
        "gasLimit": {
            "type": "BigNumber",
            "hex": "0x01630f"
        },
        "to": "0x6A023CCd1ff6F2045C3309768eAd9E68F978f6e1",
        "value": {
            "type": "BigNumber",
            "hex": "0x00"
        },
        "nonce": 937,
        "data": "0xa9059cbb000000000000000000000000fce3c3d51c7f3cc8c0f380be844e7cbad14c1c1d00000000000000000000000000000000000000000000000000027ca57357c000",
        "r": "0xa3ff01c0dcc17cfccf595fefe23468b80727e58003f364f793f6c8ed38da63b4",
        "s": "0x4a709844959b5858607b555a8ec66f90c76c00f10de44386ff80990737d126dd",
        "v": 1,
        "creates": null,
        "chainId": 100
    },
    "txReceipt": {
        "to": "0x6A023CCd1ff6F2045C3309768eAd9E68F978f6e1",
        "from": "0x52eB606f94091A2BA4f985D98C62880a9BA591B6",
        "contractAddress": null,
        "transactionIndex": 4,
        "gasUsed": {
            "type": "BigNumber",
            "hex": "0xead8"
        },
        "logsBloom": "0x00000000000000000000000000000000000000000000000000000000000000000000400000000000000000000000000000000000000000000000000000000000000800000000000000000008000000000000000000000020000000000000000000000000000000000000000000000000000000000000000000000010000000000000000000000000000000008000000000000000000000000000000000008000000000000000000010000000000000000000000000000000000000000000000044000002000000000000000000000000002000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000",
        "blockHash": "0x4023d17a5469c9dfb13bf50a63ce40d90b07a4b8e811fdba25b063ad535ba3f2",
        "transactionHash": "0x5f1ac5db6c0c31025ac19f6de22eef665e57262f9953567438827b339828e1a8",
        "logs": [
            {
                "transactionIndex": 4,
                "blockNumber": 21105871,
                "transactionHash": "0x5f1ac5db6c0c31025ac19f6de22eef665e57262f9953567438827b339828e1a8",
                "address": "0x6A023CCd1ff6F2045C3309768eAd9E68F978f6e1",
                "topics": [
                    "0xddf252ad1be2c89b69c2b068fc378daa952ba7f163c4a11628f55a4df523b3ef",
                    "0x00000000000000000000000052eb606f94091a2ba4f985d98c62880a9ba591b6",
                    "0x000000000000000000000000fce3c3d51c7f3cc8c0f380be844e7cbad14c1c1d"
                ],
                "data": "0x00000000000000000000000000000000000000000000000000027ca57357c000",
                "logIndex": 21,
                "blockHash": "0x4023d17a5469c9dfb13bf50a63ce40d90b07a4b8e811fdba25b063ad535ba3f2"
            }
        ],
        "blockNumber": 21105871,
        "confirmations": 151,
        "cumulativeGasUsed": {
            "type": "BigNumber",
            "hex": "0x168b7f"
        },
        "status": 1,
        "byzantium": true
    }
}

在交易收据中，我可以在这里看到以下数据：

 "logs": [
            {
                "transactionIndex": 4,
                "blockNumber": 21105871,
                "transactionHash": "0x5f1ac5db6c0c31025ac19f6de22eef665e57262f9953567438827b339828e1a8",
                "address": "0x6A023CCd1ff6F2045C3309768eAd9E68F978f6e1",
                "topics": [
                    "0xddf252ad1be2c89b69c2b068fc378daa952ba7f163c4a11628f55a4df523b3ef",
                    "0x00000000000000000000000052eb606f94091a2ba4f985d98c62880a9ba591b6",
                    "0x000000000000000000000000fce3c3d51c7f3cc8c0f380be844e7cbad14c1c1d"
                ],
                "data": "0x00000000000000000000000000000000000000000000000000027ca57357c000",
                "logIndex": 21,
                "blockHash": "0x4023d17a5469c9dfb13bf50a63ce40d90b07a4b8e811fdba25b063ad535ba3f2"
            }
        ],

但是如何找到我需要的信息(这些信息也显示在浏览器上)。

我想知道哪种货币被转移了多少钱。

Answer 1

你可以从日志里读到。

在这里可以找到一篇解释如何使用事件的好文章，https://betterprogramming.pub/learn-solidity-events-2801d6a99a92。

要知道“货币”或令牌，您可以阅读被调用的智能契约。交易的'to‘、'from’和'amount‘在日志中。活动的主题(请参考上面的文章)，金额在数据中。

要检查已调用的函数，您可以从事务的数据中读取。它的前4个字节(a9059cbb)是函数的签名。例如，您可以检查签名是否是“transfer”的签名。

Answer 2

您可以按主题过滤tx收据中的日志。有点像

const erc20TransferEventHash = keccak256("Transfer(address,uint256");

const erc20Transfers = [];

const logs = txReceipt.logs.filter((log) => {
  if (log.topics[0] === erc20TranferEventHash) {
    const trasferredFrom = log.topics[1];
    const transferredTo = log.topics[2];
    const amountTrasferred = log.data;
    const token = log.address;
    erc20Transfers.push({token, amount: amountTransferred, to: transferredTo, from: transferredFrom});
  }
})

然而，所有这些都要求您确切地知道事件签名是什么，什么是索引的，什么不是，等等，这样您就知道如何对它们进行解码，以及使用哪些主题来实现什么。

您也不能像前面的示例那样单独执行所有这些过滤操作，而是将etc_subscribe与相关筛选器一起使用，这样您就只能直接获得传输事件。查找更多关于日志和事件的信息。