ethereum-input-data-decoder
Ethereum smart contract transaction input data decoder
Demo
https://lab.miguelmota.com/ethereum-input-data-decoder
Install
npm install ethereum-input-data-decoder
Getting started
Pass ABI file path to decoder constructor:
const InputDataDecoder = require('ethereum-input-data-decoder');
const decoder = new InputDataDecoder(`${__dirname}/abi.json`);
Alternatively, you can pass ABI array object to constructor;
const abi = [{ ... }]
const decoder = new InputDataDecoder(abi);
example abi
Then you can decode input data:
const data = `0x67043cae0000000000000000000000005a9dac9315fdd1c3d13ef8af7fdfeb522db08f020000000000000000000000000000000000000000000000000000000058a20230000000000000000000000000000000000000000000000000000000000040293400000000000000000000000000000000000000000000000000000000000000a0f3df64775a2dfb6bc9e09dced96d0816ff5055bf95da13ce5b6c3f53b97071c800000000000000000000000000000000000000000000000000000000000000034254430000000000000000000000000000000000000000000000000000000000`;
const result = decoder.decodeData(data);
console.log(result);
{
"name": "registerOffChainDonation",
"types": [
"address",
"uint256",
"uint256",
"string",
"bytes32"
],
"inputs": [
<BN: 5a9dac9315fdd1c3d13ef8af7fdfeb522db08f02>,
<BN: 58a20230>,
<BN: 402934>,
"BTC",
<Buffer f3 df ... 71 c8>
]
}
Example using input response from web3.getTransaction:
web3.eth.getTransaction(txHash, (error, txResult) => {
const result = decoder.decodeData(txResult.input);
console.log(result);
});
Decoding Big Numbers
All numbers are returned in big number format to preserve precision.
Here's an example of how to convert the big number to a human readable format.
console.log(result.inputs[0].toString(10))
console.log(result.inputs[0].toNumber())
Please keep in mind that JavaScript only supports numbers up to 64 bits. Solidity numbers can be up to 256 bits, so you run the risk of truncation when casting or having the big number library error out when trying to parse a large number to a JavaScript Number type.
const n = new BN("543534254523452352345234523455")
console.log(n.toString(10))
console.log(n.toNumber())
CLI
Install
npm install -g ethereum-input-data-decoder
Usage
$ ethereum_input_data_decoder --help
Ethereum smart contract transaction input data decoder
Usage
$ ethereum_input_data_decoder [flags] [input]
Options
--abi, -a ABI file path
--input, -i Input data file path
Examples
$ ethereum_input_data_decoder --abi token.abi --input data.txt
$ ethereum_input_data_decoder --abi token.abi "0x23b872dd..."
Example
Pass ABI file and input data as file:
$ ethereum_input_data_decoder --abi abi.json --input data.tx
name registerOffChainDonation
address 0x5a9dac9315fdd1c3d13ef8af7fdfeb522db08f02
uint256 1487012400
uint256 4204852
string BTC
bytes32 0xf3df64775a2dfb6bc9e09dced96d0816ff5055bf95da13ce5b6c3f53b97071c8
Pass ABI file and input data as string:
$ ethereum_input_data_decoder --abi abi.json 0x67043cae0...000000
name registerOffChainDonation
address 0x5a9dac9315fdd1c3d13ef8af7fdfeb522db08f02
uint256 1487012400
uint256 4204852
string BTC
bytes32 0xf3df64775a2dfb6bc9e09dced96d0816ff5055bf95da13ce5b6c3f53b97071c8
You can also pipe the input data:
$ cat data.txt | ethereum_input_data_decoder --abi abi.json
name registerOffChainDonation
address 0x5a9dac9315fdd1c3d13ef8af7fdfeb522db08f02
uint256 1487012400
uint256 4204852
string BTC
bytes32 0xf3df64775a2dfb6bc9e09dced96d0816ff5055bf95da13ce5b6c3f53b97071c8
Test
npm test
Development
- Clone repository:
git clone git@github.com:miguelmota/ethereum-input-data-decoder.git
cd ethereum-input-data-decoder/
- Install dependencies:
npm install
-
Make changes.
-
Run tests:
npm test
- Run linter:
npm run lint:fix
FAQ
License
MIT