bitcoin-rpc
bitcoin-rpc is a typesafe bitcoind RPC client written in and to be used with Scala 2.12 or 2.13. Under the hood, it's using http4s, circe and cats-effect. It's in active development, but no official public release has been scheduled yet. We appreciate external contributions, please check issues for inspiration. For all examples, check: src/main/scala/examples.
Add Dependency
Simply add the following dependency to your project.
libraryDependencies += "io.tokenanalyst" %% "bitcoin-rpc" % "2.4.0",
Example: Fetch Bitcoin Block
This is a simple example of how the RPCClient is generally used. We're using Cats Resources here which automatically deallocate any opened resources after use.
import cats.effect.{ExitCode, IO, IOApp}
import scala.concurrent.ExecutionContext.global
import io.tokenanalyst.bitcoinrpc.RPCClient
import io.tokenanalyst.bitcoinrpc.bitcoin.Syntax._
object GetBlockHash extends IOApp {
def run(args: List[String]): IO[ExitCode] = {
implicit val ec = global
RPCClient
.bitcoin(
Seq(127.0.0.1),
username = "tokenanalyst",
password = "!@#$%^&*(2009"
)
.use { bitcoin =>
for {
block <- bitcoin.getBlockByHash(
"0000000000000000000759de6ab39c2d8fb01e4481ba581761ddc1d50a57358d"
)
_ <- IO { println(block) }
} yield ExitCode(0)
}
}
}
Example: Catch up from block zero
This example makes use of the EnvConfig import, which automatically configures RPC via ENV flags exported in the shell. The environment flags for it are BITCOIN_RPC_HOSTS, BITCOIN_RPC_USERNAME, BITCOIN_RPC_PASSWORD.
import io.tokenanalyst.bitcoinrpc.Bitcoin
import io.tokenanalyst.bitcoinrpc.{RPCClient, Config}
import io.tokenanalyst.bitcoinrpc.bitcoin.Syntax._
object CatchupFromZero extends IOApp {
def loop(rpc: Bitcoin, current: Long = 0L, until: Long = 10L): IO[Unit] =
for {
block <- rpc.getBlockByHeight(current)
_ <- IO { println(block) }
l <- if (current + 1 < until) loop(rpc, current + 1, until) else IO.unit
} yield l
def run(args: List[String]): IO[ExitCode] = {
implicit val ec = global
implicit val config = Config.fromEnv
RPCClient
.bitcoin(config.hosts, config.port, config.username, config.password)
.use { rpc =>
for {
_ <- loop(rpc)
} yield ExitCode(0)
}
}
}
Environment Variables
| variable | description | type |
|---|---|---|
| BITCOIN_RPC_HOSTS | Comma-seperated IP list or hostname of full nodes | String |
| BITCOIN_RPC_USERNAME | RPC username | Optional String |
| BITCOIN_RPC_PASSWORD | RPC password | Optional String |
| BITCOIN_RPC_PORT | RPC port when not default | Optional Int |
| BITCOIN_RPC_ZEROMQ_PORT | ZeroMQ port when not default | Optional Int |
Supported Bitcoin methods
| Bitcoind RPC methods | description | bitcoin-rpc method |
|---|---|---|
| getblockhash | Gets the block hash at a specific height | getBlockHash(height: Long) |
| getbestblockhash | Gets the block tip hash | getBestBlockHash() |
| getblock | Gets the block with transaction ids | getBlockByHash(hash: String) |
| getblockhash, getblock | Gets the block with transaction ids | getBlockByHeight(height: Long) |
| getrawtransaction | Gets raw transaction data | getTransaction(hash: String) |
| batch of getrawtransaction | Gets raw transaction data | getTransactions(hashes: Seq[String]) |
| estimatesmartfee | Estimates fee for include in block n | estimateSmartFee(height: Long) |
| usage of ZeroMQ | Gets next block hash subscription | getNextBlockHash() |
