bitcoin-s/docs/rpc/bitcoind.md

id	title
rpc-bitcoind	bitcoind/Bitcoin Core

Note: bitcoin-s-bitcoind-rpc requires you to have bitcoind (Bitcoin Core daemon) installed. Grab this at bitcoincore.org

The Bitcoin Core RPC client in Bitcoin-S currently supports the Bitcoin Core 0.16 and 0.17 version lines. It can be set up to work with both local and remote Bitcoin Core servers.

Connecting to a local bitcoind instance

import scala.concurrent._
import akka.actor.ActorSystem

import org.bitcoins.{rpc, core}
import core.currency.Bitcoins
import rpc.client.common._
import rpc.config.BitcoindInstance

implicit val actorSystem: ActorSystem = ActorSystem.create()
implicit val ec: ExecutionContext = actorSystem.dispatcher

// data directory defaults to ~/.bitcoin on Linux and
// ~/Library/Application Support/Bitcoin on macOS
val bitcoindInstance = BitcoindInstance.fromDatadir()

// alternative:
import java.io.File
val dataDir = new File("/my/bitcoin/data/dir")
val otherInstance = BitcoindInstance.fromDatadir(dataDir)


val client = new BitcoindRpcClient(bitcoindInstance)

val balance: Future[Bitcoins] = for {
  _ <- client.start()
  balance <- client.getBalance
} yield balance

Connecting to a remote bitcoind

First, we create a secure connection to our bitcoind instance by setting up a SSH tunnel:

$ ssh -L 8332:localhost:8332  \
         my-cool-user@my-cool-website.com

Note: the port number '8332' is the default for mainnet. If you want to connect to a testnet bitcoind, the default port is '18332'

Now that we have a secure connection between our remote bitcoind, we're ready to create the connection with our RPC client

import akka.actor.ActorSystem
import java.net.URI
import scala.concurrent._

import org.bitcoins.core.config._
import org.bitcoins.rpc.config._
import org.bitcoins.rpc.client.common._

val username = "FILL_ME_IN" //this username comes from 'rpcuser' in your bitcoin.conf file
val password = "FILL_ME_IN" //this password comes from your 'rpcpassword' in your bitcoin.conf file
val rpcPort = 8332 //this is default port for mainnet, 18332 for testnet/regtest


val authCredentials = BitcoindAuthCredentials(
  username = username,
  password = password,
  rpcPort = rpcPort
)

val bitcoindInstance = {
  BitcoindInstance (
    network = MainNet,
    uri = new URI(s"http://localhost:${authCredentials.rpcPort + 1}"),
    rpcUri = new URI(s"http://localhost:${authCredentials.rpcPort}"),
    authCredentials = authCredentials
  )
}

implicit val system: ActorSystem = ActorSystem.create()
implicit val ec: ExecutionContext = system.dispatcher

val rpcCli = new BitcoindRpcClient(bitcoindInstance)

rpcCli.getBalance.onComplete { case balance =>
  println(s"Wallet balance=${balance}")
  system.terminate()
}

Testing

To test the Bitcoin-S RPC project you need both version 0.16 and 0.17 of Bitcoin Core. A list of current and previous releases can be found here.

You then need to set environment variables to indicate where Bitcoin-S can find the different versions:

$ export BITCOIND_V16_PATH=/path/to/v16/bitcoind
$ export BITCOIND_V17_PATH=/path/to/v17/bitcoind

If you just run tests testing common functionality it's enough to have either version 0.16 or 0.17 on your PATH.

To run all RPC related tests:

$ bash sbt bitcoindRpcTest/test