Decode transaction input

[wafcio]

JSON RPC getTransactionByHash returns transaction details with "input" data. I have tried to find an easy way to decode the input field, but I haven't been able to find one.

The problem is that the first 32 bytes point to the function name, and the rest are related to decoding based on ABI. I need help finding a way to select a proper function from ABI.

[wafcio]

I have found solution, it would be great to have it implemented in gem

# abi - JSON abi
# tx_input - Transaction input data

abi = abi.select { |a| a["name"].present? }

function_signatures =
  abi.each_with_object({}) do |a, hsh|
    hsh[Eth::Abi::Event.compute_topic(a)[0, 10]] = a
  end

types = function_signatures[tx_input[0, 10]]["inputs"].map { |input| input["type"] }

Eth::Abi.decode(types, tx_input[10..-1])

[q9f]

Sounds good to me. Do you mind supplying a test case or data?

Feel free to suggest a PR!

[wafcio]

@q9f I don't know enough about eth.rb codebase. Moreover, it will be good to add parsing transaction log data