Opinionated Swift wrapper around LibWally, a collection of useful primitives for cryptocurrency wallets.
Supports a minimal set of features based on v0.7.7. See also original docs.
- Core Functions
- base58 encode / decode
- Crypto Functions
- sign ECDSA, convert to DER
- Address Functions
- Parse to scriptPubKey
- Generate from scriptPubKey #7 (wishlist, done for SegWit)
- Derive
- WIF
- Detect bech32 typos #4 (wishlist)
- BIP32 Functions
- Derive scriptPubKey #6 (wishlist)
- BIP38 Functions
- BIP39 Functions
- Script Functions
- Serialize scriptPubKey
- Determine scriptPubkey type
- PSBT functions
- Parse and serialize (base64 / binary)
- Check completeness and extract transaction
- Transaction Functions
- Compose and sign transaction
- Calculate fee
Items marked with wishlist are not (yet) available upstream.
Multisig as well as Elements specific functions such as confidential addresses are not implemented.
Works with iOs 11+ on 64-bit devices and the simulator.
Usage
Derive address from a seed:
let mnemonic = BIP39Mnemonic("abandon abandon abandon abandon abandon abandon abandon abandon abandon abandon abandon about")
let masterKey = HDKey(mnemonic.seedHex("bip39 passphrase"))!
masterKey.fingerprint.hexString
let path = BIP32Path("m/44'/0'/0'")!
let account = try! masterKey.derive(path)
account.xpub
account.address(.payToWitnessPubKeyHash)
Derive address from an xpub:
let account = HDKey("xpub6ASuArnXKPbfEwhqN6e3mwBcDTgzisQN1wXN9BJcM47sSikHjJf3UFHKkNAWbWMiGj7Wf5uMash7SyYq527Hqck2AxYysAA7xmALppuCkwQ")
let receivePath = BIP32Path("0/0")!
key = account.derive(receivePath)
key.address(.payToPubKeyHash) # => 1JQheacLPdM5ySCkrZkV66G2ApAXe1mqLj
Parse an address:
var address = Address("bc1q6zwjfmhdl4pvhvfpv8pchvtanlar8hrhqdyv0t")
address?.scriptPubKey # => 0014d09d24eeedfd42cbb12161c38bb17d9ffa33dc77
address?.scriptPubKey.type # => .payToWitnessPubKeyHash
Create and sign a transaction:
let txId = "400b52dab0a2bb5ce5fdf5405a965394b43a171828cd65d35ffe1eaa0a79a5c4"
let vout: UInt32 = 1
let amount: Satoshi = 10000
let witness = Witness(.payToWitnessPubKeyHash(key.pubKey))
let input = TxInput(Transaction(txId)!, vout, amount, nil, witness, scriptPubKey)!
transaction = Transaction([input], [TxOutput(destinationAddress.scriptPubKey, amount - 110)])
transaction.feeRate // Satoshi per byte
let accountPriv = HDKey("xpriv...")
let privKey = try! accountPriv.derive(BIP32Path("0/0")!)
transaction.sign([privKey])
transaction.description # transaction hex
See also the included Playground and tests.
Install
## CocoaPods:
Add to your Podfile:
pod 'LibWally', :git => 'https://github.com/blockchain/LibWally-Swift.git', :tag => 'v0.0.1', :submodules => true
and then run:
pod install --verbose
Carthage:
Add to your Cartfile:
github "blockchain/libwally-swift" == 0.0.1
and then run:
carthage update libwally-swift
Build
Install dependencies:
brew install gnu-sed
Clone the repository, including submodules:
git clone https://github.com/blockchain/libwally-swift.git --recurse-submodules
Build libwally-core:
./build-libwally.sh -dsc