README.md

Go transaction decoder

This is a go ethereum transaction decoder, it is used for decode input field like below example.

{
  "txHash": "0x76066e2722dfb3a61988b7c9d2be2cb20cb4c0ab5e4ce874641f753ab5287024",
  "txContents": {
    "from": "0x98e55d2288385bc1b0ebbe0e56eac6aeb099c496",
    "gas": "0x21a68",
    "gasPrice": "0x24c988ac00",
    "hash": "0x76066e2722dfb3a61988b7c9d2be2cb20cb4c0ab5e4ce874641f753ab5287024",
    "input": "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",
    "nonce": "0x304",
    "value": "0x0",
    "v": "0x26",
    "r": "0x62c507995886100ae49cd60c7c0c5e97b52a4427cbcc3874626d303758d7a46d",
    "s": "0x425c5e2b00867224d42d0a54a36010a69ebd5c007473f7e8213737fb90cf8823",
    "to": "0x7a250d5630b4cf539739df2c5dacb4c659f2488d"
  }
}

Get started

git clone https://github.com/huahuayu/go-transaction-decoder.git
cd go-transaction-decoder
go run main.go

output:

{AmountOutMin:+73018504691422977465158 Path:[0xC02aaA39b223FE8D0A0e5C4F27eAD9083C756Cc2 0x6B175474E89094C44Da98b954EedeAC495271d0F] To:0xcc5B73E4dae936F3BD830F048303c076EaE3edF9 Deadline:+1609744624}

Notes

0). The input data is in hex format.

1). In order to decode, the smart contract's abi is needed, you can copy it from etherscan or generate it by solc.

2). From the 3rd char to 9th char(include) of the input field is the function name hash. Without abi, in theory, you can't get the function name, but with abi, by looping the function name, do hash and compare, you can tell the function.

3). From 10th char to the end is the actual payload, in order to decode, you need define the input struct to map the data.

Todos

• decode any input data for any given transaction hash without 1.) hardcode the abi 2.) define the function input struct in advance, which means:
  • get the abi by transaction hash first, if the contract is published
  • identfy the function name
  • decode the function input

Other decoder

nodejs decoder

Reference

How to decode input data with ABI using golang?