ledger-eth-lib

This is a WIP. Consider it alpha

This is a library to interact with ledger-app-eth, the Ethereum app for the Ledger hardware wallets. It's goal is to make interfacing with the Ledger nice and simple with well known Ethereum+Python tools.

Web3.py Integration

ledger-eth-lib provides a Web3.py middleware. It will automatically intercept the relevant JSON-RPC calls and respond with data from your Ledger device.

from web3.auto import w3
from ledgereth.web3 import LedgerSignerMiddleware
w3.middleware_onion.add(LedgerSignerMiddleware)

Intercepted JSON-RPC methods:

• eth_sendTransaction
• eth_accounts

Quickstart

Get Accounts

Fetch the availible accounts (currently only default).

from ledgereth import get_accounts
accounts = get_accounts()
my_account = accounts[0]

Create and Sign a Transaction

Create a transaction object and sign it.

from ledgereth import create_transaction
tx = create_transaction(
    '0xb78f53524ae9d465279e7c3495f71d5db2419e13',  # to
    '0x4dae53ee778a324bd317bd270d6227406b6bd4ec',  # from
    int(1e18),  # value
    int(1e5),  # gas limit
    int(1e9),  # gas price
    1  # nonce
)
# TODO: Double check this
signature = '0x{}{}{}'.format(
    hex(tx.v)[2:],
    hex(tx.r)[2:],
    hex(tx.s)[2:],
)

Sign an Existing Transaction Object

Sign a Transaction object from pyethereum(or similar RLP serializable):

from ledgereth import sign_transaction
tx = sign_transaction(tx)
# TODO: Double check this
signature = '0x{}{}{}'.format(
    hex(tx.v)[2:],
    hex(tx.r)[2:],
    hex(tx.s)[2:],
)

API

get_accounts(dongle: Any = None)

Fetch a List of accounts.

NOTE: This will currently only return the default/primary account from the device.

sign_transaction(tx: Serializable, dongle: Any = None)

Sign a rlp.Serializable transaction.

create_transaction(to: bytes, sender: bytes, value: int, gas: int, gas_price: int, nonce: int, data: bytes, dongle: Any = None)

Create and sign an rlp.Serializable transaction from provided params

TODO

• Add fake dongle support to pytest suite so tests can be run without a real Ledger and human interaction
• Fill out tests
• Add messaging signing support
• Add support for multiple accounts(different derivations?)