BSV-ex v0.4.1 BSV View Source

BSV-ex is a general purpose library for building Bitcoin SV applications in Elixir. The intent of this library is to be broadly comparable in scope, and cross compatible with Money Button's BSV Javascript library.

Features

Currently this library offers the following functionality:

• Transaction parsing, construction, signing and serialization
• Keypair generation and address encoding and decoding
• BIP-39 mnemonic phrase generation and deterministic keys
• Bitcoin message signing (Electrum compatible)
• ECIES encryption/decryption (Electrum compatible)
• Wide range of both Bitcoin and non-Bitcoin specific crypto functions
• Full featured, pure Elixir Bitcoin Script VM

Full documentation can be found at https://hexdocs.pm/bsv.

Note to developers

This is a new library and new codebase. As such developers should proceed with caution and test using testnet and small value transactions. In future versions the API is subject to change as the library is developed towards maturity.

Installation

The package can be installed by adding bsv to your list of dependencies in mix.exs:

def deps do
  [
    {:bsv, "~> 0.4"}
  ]
end

By default, Curvy - a pure Elixir implementation of secp256k1 is used. Optionally libsecp256k1 can by used by adding it to your dependencies. libtool, automake and autogen are required in order for the package to compile with libsecp256k1.

def deps do
  [
    {:bsv, "~> 0.4"},
    {:libsecp256k1, "~> 0.1"}
  ]
end

Usage

Many examples are demonstrated throughout the documentation, but see the following for some quick-start examples:

Key pairs and addresses

For more examples refer to BSV.KeyPair and BSV.Address.

iex> keys = BSV.KeyPair.generate
%BSV.KeyPair{
  network: :main,
  private_key: <<1, 249, 98, 144, 230, 172, 5, 56, 197, 143, 133, 240, 144, 223, 25, 32, 55, 42, 159, 26, 128, 66, 149, 49, 235, 179, 116, 11, 209, 235, 240, 163>>,
  public_key: <<3, 173, 251, 14, 108, 217, 224, 80, 133, 244, 200, 33, 191, 137, 80, 62, 141, 133, 166, 201, 224, 141, 101, 152, 144, 92, 237, 54, 220, 131, 58, 26, 4>>
}

iex> address = BSV.Address.from_public_key(keys)
...> |> BSV.Address.to_string
"1MzYtHPymTjgxx9npR6Pu9ZCUhtU9hHYTL"

Mnemonic phrase and deterministic keys

For further details and examples refer to BSV.Mnemonic, BSV.Extended.PrivateKey, BSV.Extended.PublicKey and BSV.Extended.Children.

iex> mnemonic = BSV.Mnemonic.generate
"various attitude grain market food wheat arena disagree soccer dust wrestle auction fiber wrestle sort wonder vital gym ill word amazing sniff have biology"

iex> master = BSV.Mnemonic.to_seed(mnemonic)
...> |> BSV.Extended.PrivateKey.from_seed
%BSV.Extended.PrivateKey{
  chain_code: <<164, 12, 192, 154, 59, 209, 85, 172, 76, 7, 42, 138, 247, 125, 161, 30, 135, 25, 124, 160, 170, 234, 126, 162, 228, 146, 135, 232, 67, 181, 219, 91>>,
  child_number: 0,
  depth: 0,
  fingerprint: <<0, 0, 0, 0>>,
  key: <<111, 24, 247, 85, 107, 58, 162, 225, 135, 190, 185, 200, 226, 131, 68, 152, 159, 111, 232, 166, 21, 211, 235, 180, 140, 190, 109, 39, 31, 33, 107, 17>>,
  network: :main,
  version_number: <<4, 136, 173, 228>>
}

iex> child_address = master
...> |> BSV.Extended.Children.derive("m/44'/0'/0'/0/0")
...> |> BSV.Address.from_public_key
...> |> BSV.Address.to_string
"1F6fuP7HrBY8aeUazXZitaAsgpsJQFfUun"

Creating transactions

For further details and examples refer to BSV.Transaction, BSV.Transaction.Input, BSV.Transaction.Output and BSV.Script.

iex> script = %BSV.Script{}
...> |> BSV.Script.push(:OP_FALSE)
...> |> BSV.Script.push(:OP_RETURN)
...> |> BSV.Script.push("hello world")
%BSV.Script{chunks: [:OP_FALSE, :OP_RETURN, "hello world"]}

iex> output = %BSV.Transaction.Output{script: script}
%BSV.Transaction.Output{
  amount: 0,
  satoshis: 0,
  script: %BSV.Script{
    chunks: [:OP_FALSE, :OP_RETURN, "hello world"]
  }
}

iex> tx = %BSV.Transaction{}
...> |> BSV.Transaction.spend_from(utxo)
...> |> BSV.Transaction.add_output(output)
...> |> BSV.Transaction.change_to("15KgnG69mTbtkx73vNDNUdrWuDhnmfCxsf")
...> |> BSV.Transaction.sign(private_key)
...> |> BSV.Transaction.serialize(encoding: :hex)
"010000000142123cac628be8df8bbf1fc21449c94bb8b81bc4a5960193be37688694626f49000000006b483045022100df13af549e5f6a23f70e0332856a0934a6fbbf7edceb19b15cafd8d3009ce12f02205ecf6b0f9456354de7c0b9d6b8877dac896b72edd9f7e3881b5ac69c82c03aac41210296207d8752d01b1cf8de77d258c02dd7280edc2bce9b59023311bbd395cbe93affffffff0100000000000000000e006a0b68656c6c6f20776f726c6400000000"