Eth

A simple library to build and sign Ethereum transactions. Allows separataion of key and node management. Sign transactions and handle keys anywhere you can run ruby, boradcast transactions through any node.

Installation

Add this line to your application’s Gemfile:

gem 'eth'

And then execute:

$ bundle

Or install it yourself as:

$ gem install eth

Usage

Keys

Create a new key:

key = Eth::Key.new

Or import and existing one:

old_key = Eth::Key.new priv: private_key

Transactions

Build a transaction from scratch:

tx = Eth::Tx.new({
  data: hex_data,
  gas_limit: 21_000,
  gas_price: 3_141_592,
  nonce: 1,
  to: key2.address,
  value: 1_000_000_000_000,
})

Or decode an encoded raw transaction:

tx = Eth::Tx.decode hex

Configure

In order to prevent replay attacks, you must specify which Ethereum chain your transactions are created for. See EIP 155 for more detail.

Eth.configure do |config|
  config.chain_id = 1 # nil by default, meaning valid on any chain
end

Then sign the transaction:

tx.sign key

Get the raw transaction with tx.hex, and broadcast it through any Ethereum node. Or, just get the TXID with tx.hash.

Contributing

Bug reports and pull requests are welcome on GitHub at https://github.com/se3000/ethereum-tx. Tests are encouraged.

Tests

First install the Ethereum common tests:

git submodule update --init

Then run the associated tests:

rspec

License

The gem is available as open source under the terms of the MIT License.

TODO

Better test suite.
Expose API for HD keys.
Support signing with libsecp256k1.

Modules

Classes

Eth