Bitcoinex

Bitcoinex is striving to be the best and most up-to-date Bitcoin Library for Elixir.

Documentation

Documentation is available on hexdocs.pm.

Current Utilities

• Serialization and validation for Bech32 and Base58.
• Support for standard on-chain scripts (P2PKH..P2WPKH) and Bolt#11 Lightning Invoices.
• Transaction serialization.
• Basic PSBT (BIP174) parsing.

Usage

With Hex:

{:bitcoinex, "~> 0.1.7"}

Local:

$ mix deps.get
$ mix compile

Examples

Decode a Lightning Network invoice:

Bitcoinex.LightningNetwork.decode_invoice("lnbc2500u1pvjluezpp5qqqsyqcyq5rqwzqfqqqsyqcyq5rqwzqfqqqsyqcyq5rqwzqfqypqdq5xysxxatsyp3k7enxv4jsxqzpuaztrnwngzn3kdzw5hydlzf03qdgm2hdq27cqv3agm2awhz5se903vruatfhq77w3ls4evs3ch9zw97j25emudupq63nyw24cg27h2rspfj9srp")

{:ok,
  %Bitcoinex.LightningNetwork.Invoice{
    amount_msat: 250000000,
    description: "1 cup coffee",
    description_hash: nil,
    destination: "03e7156ae33b0a208d0744199163177e909e80176e55d97a2f221ede0f934dd9ad",
    expiry: 60,
    fallback_address: nil,
    min_final_cltv_expiry: 18,
    network: :mainnet,
    payment_hash: "0001020304050607080900010203040506070809000102030405060708090102",
    route_hints: [],
    timestamp: 1496314658
  }}

Parse a BIP-174 Partially Signed Bitcoin Transaction:

Bitcoinex.PSBT.decode("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")

{:ok,
  %Bitcoinex.PSBT{
   global: %Bitcoinex.PSBT.Global{
     proprietary: nil,
     unsigned_tx: %Bitcoinex.Transaction{...},
   inputs: [
     %Bitcoinex.PSBT.In{
       bip32_derivation: [
         %{
           derivation: "b4a6ba67000000800000008004000080",
           public_key: "03b1341ccba7683b6af4f1238cd6e97e7167d569fac47f1e48d47541844355bd46"
         },
         %{
           derivation: "b4a6ba67000000800000008005000080",
           public_key: "03de55d1e1dac805e3f8a58c1fbf9b94c02f3dbaafe127fefca4995f26f82083bd"
         }
       ],
       final_scriptsig: nil,
       final_scriptwitness: nil,
       non_witness_utxo: nil,
       partial_sig: %{
         public_key: "03b1341ccba7683b6af4f1238cd6e97e7167d569fac47f1e48d47541844355bd46",
         signature: "304302200424b58effaaa694e1559ea5c93bbfd4a89064224055cdf070b6771469442d07021f5c8eb0fea6516d60b8acb33ad64ede60e8785bfb3aa94b99bdf86151db9a9a01"
       },
       por_commitment: nil,
       proprietary: nil,
       redeem_script: "0020771fd18ad459666dd49f3d564e3dbc42f4c84774e360ada16816a8ed488d5681",
       sighash_type: nil,
       witness_script: "522103b1341ccba7683b6af4f1238cd6e97e7167d569fac47f1e48d47541844355bd462103de55d1e1dac805e3f8a58c1fbf9b94c02f3dbaafe127fefca4995f26f82083bd52ae",
       witness_utxo: %Bitcoinex.Transaction.Out{
         script_pub_key: "a9146345200f68d189e1adc0df1c4d16ea8f14c0dbeb87",
         value: 199909013
       }
     }
   ],
   outputs: []
  }}

Handle bitcoin addresses:

{:ok, {:mainnet, witness_version, witness_program}} = Bitcoinex.Segwit.decode_address("bc1qw508d6qejxtdg4y5r3zarvary0c5xw7kv8f3t4")

Bitcoinex.Segwit.encode_address(:mainnet, witness_version, witness_program)

{:ok, "bc1qw508d6qejxtdg4y5r3zarvary0c5xw7kv8f3t4"}

Decoding a PSBT

We have a simple script for decoding a PSBT to view the inputs and outputs. Once you've installed elixir, erlang, and the mix dependencies, you can run the command below:

mix run scripts/decode_psbt.exs <psbt_file_path> 

Roadmap

Continued support for on-chain and off-chain functionality including:

• Full script support including validation.
• Block serialization.
• Transaction creation.
• Broader BIP support including BIP32.

Contributing

We have big goals and this library is still in a very early stage. Contributions and comments are very much welcome.

DISCLAIMER

This software is not recommended for use in handling real funds. The addresses, public keys, and signatures generated by this library are not recommended to be used for sending or receiving real funds.