bitcoin-s/website/versioned_docs/version-0.2.0/applications/wallet.md

title	id	original_id
Wallet	version-0.2.0-wallet	wallet

Bitcoin-S comes bundled with a rudimentary Bitcoin wallet. This wallet is capable of managing private keys, generating addresses, constructing and signing transactions, among other things. It is BIP32/BIP44/BIP49/BIP84 compatible.

This wallet is currently only released as a library, and not as a binary. This is because it (nor the documentation) is not deemed production ready. Use at your own risk, and without too much money depending on it.

Creating a wallet

This guide shows how to create a Bitcoin-S wallet and then peer it with a bitcoind instance that relays information about what is happening on the blockchain through the P2P network.

This is useful if you want more flexible signing procedures in the JVM ecosystem and more granular control over your UTXOs with popular database like Postgres, SQLite, etc.

This code snippet you have a running bitcoind instance, locally on regtest.

implicit val ec = scala.concurrent.ExecutionContext.global

import com.typesafe.config.ConfigFactory
val config = ConfigFactory.parseString {
    """
    | bitcoin-s {
    |   network = regtest
    | }
    """.stripMargin
}

import java.nio.file.Files
val datadir = Files.createTempDirectory("bitcoin-s-wallet")

import org.bitcoins.wallet.config.WalletAppConfig
implicit val walletConfig = WalletAppConfig(datadir, config)

// we also need to store chain state for syncing purposes
import org.bitcoins.chain.config.ChainAppConfig
implicit val chainConfig = ChainAppConfig(datadir, config)

// when this future completes, we have
// created the necessary directories and
// databases for managing both chain state
// and wallet state
import scala.concurrent._
val configF: Future[Unit] = for {
    _ <- walletConfig.initialize()
    _ <- chainConfig.initialize()
} yield ()

import org.bitcoins.rpc.config.BitcoindInstance
val bitcoindInstance = BitcoindInstance.fromDatadir()

import org.bitcoins.rpc.client.common.BitcoindRpcClient
val bitcoind = BitcoindRpcClient(bitcoindInstance)

// when this future completes, we have
// synced our chain handler to our bitcoind
// peer
import org.bitcoins.chain.api.ChainApi
val syncF: Future[ChainApi] = configF.flatMap { _ =>
    val getBestBlockHashFunc = { () =>
        bitcoind.getBestBlockHash
    }

    import org.bitcoins.core.crypto.DoubleSha256DigestBE
    val getBlockHeaderFunc = { hash: DoubleSha256DigestBE =>
        bitcoind.getBlockHeader(hash).map(_.blockHeader)
    }


    import org.bitcoins.chain.models._
    import org.bitcoins.chain.blockchain.ChainHandler
    val blockHeaderDAO = BlockHeaderDAO()
    val compactFilterHeaderDAO = CompactFilterHeaderDAO()
    val compactFilterDAO = CompactFilterDAO()
    val chainHandler = ChainHandler(
        blockHeaderDAO,
        compactFilterHeaderDAO,
        compactFilterDAO,
        blockchains = Vector.empty,
        blockFilterCheckpoints = Map.empty)

    import org.bitcoins.chain.blockchain.sync.ChainSync
    ChainSync.sync(chainHandler, getBlockHeaderFunc, getBestBlockHashFunc)
}

// once this future completes, we have a initialized
// wallet
import org.bitcoins.wallet.api.LockedWalletApi
import org.bitcoins.wallet.api.InitializeWalletSuccess
import org.bitcoins.wallet.Wallet
import org.bitcoins.core.api._
val walletF: Future[LockedWalletApi] = configF.flatMap { _ =>
    Wallet.initialize(NodeApi.NoOp, ChainQueryApi.NoOp).collect {
        case InitializeWalletSuccess(wallet) => wallet
    }
}


// when this future completes, ww have sent a transaction
// from bitcoind to the Bitcoin-S wallet
import org.bitcoins.core.crypto._
import org.bitcoins.core.protocol.transaction._
import org.bitcoins.core.currency._
val transactionF: Future[(Transaction, Option[DoubleSha256DigestBE])] = for {
    wallet <- walletF
    address <- wallet.getNewAddress()
    txid <- bitcoind.sendToAddress(address, 3.bitcoin)
    transaction <- bitcoind.getRawTransaction(txid)
} yield (transaction.hex, transaction.blockhash)

// when this future completes, we have processed
// the transaction from bitcoind, and we have
// queried our balance for the current balance
val balanceF: Future[CurrencyUnit] = for {
    wallet <- walletF
    (tx, blockhash) <- transactionF
    _ <- wallet.processTransaction(tx, blockhash)
    balance <- wallet.getBalance
} yield balance

balanceF.foreach { balance =>
    println(s"Bitcoin-S wallet balance: $balance")
}