Class: EvmTxInput::Decoder

Inherits:
Object
  • Object
show all
Defined in:
lib/evm_tx_input/decoder.rb

Overview

A class containing a set of helpers to decode transactions input data into human-readable values by provided contract’s ABI

Instance Attribute Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(abi = []) ⇒ Decoder

Constructor of EvmTxInput::Decoder

Parameters:

  • abi (Array) (defaults to: []) —

    parsed contract ABI



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# File 'lib/evm_tx_input/decoder.rb', line 15

def initialize(abi = [])
  @abi = abi
  @method_definitions = method_definitions_by_id(abi)
end

Instance Attribute Details

#abi ⇒ Hash (readonly)

parsed contract ABI

Returns:

  • (Hash) —

    the current value of abi



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# File 'lib/evm_tx_input/decoder.rb', line 9

def abi
  @abi
end

#method_definition ⇒ Hash (readonly)

parsed contract ABI

Returns:

  • (Hash) —

    the current value of method_definition



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# File 'lib/evm_tx_input/decoder.rb', line 9

def method_definition
  @method_definition
end

#method_definitions ⇒ Object (readonly)

Returns the value of attribute method_definitions.



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# File 'lib/evm_tx_input/decoder.rb', line 10

def method_definitions
  @method_definitions
end

Instance Method Details

#decode_input(input_data) ⇒ EvmTxInput::Function

Decodes transaction input data

Parameters:

  • input_data (String) —

    binary encoded input data from transaction

Returns:

Raises:



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# File 'lib/evm_tx_input/decoder.rb', line 24

def decode_input(input_data)
  input_data = input_data[2..] if input_data.start_with?('0x')
  method_id = input_data[0...8]
  definition = method_definitions[method_id]
  raise Error, "ABI does not contain method with #{method_id} ID" unless definition

  Function.new(method_id, definition['name'], extract_arguments(input_data, definition))
end