tommccabe / bitcoin-s

An implementation of the Bitcoin protocol in the Scala programming language

#Bitcoin-S

Bitcoin-S is an implementation of the Bitcoin protocol in the Scala programming language.

##Prerequisites:

• Scala: http://www.scala-lang.org/
• SBT: http://www.scala-sbt.org/download.html
• Bitcoin-Core: https://bitcoin.org/en/download
• If using Windows, set your PATH: https://github.com/bitcoin-s/bitcoin-s/blob/master/README/EnvironmentPaths.md

##Getting Started

Import/build the project using your preferred IDE.

We can start a bitcoin server in a Scala console by first importing the serverInitiation file and creating a instance of the ServerInitiation class.

scala> import org.scalacoin.protocol.server.ServerInitiation
import org.scalacoin.protocol.server.ServerInitiation

scala> val testNet = new ServerInitiation("bitcoind -testnet")
testNet: org.scalacoin.protocol.server.ServerInitiation = org.scalacoin.protocol.server.ServerInitiation@13ad926

##RPCs

For a complete list of RPCs for bitcoin and their descriptions, refer to https://bitcoin.org/en/developer-reference#remote-procedure-calls-rpcs.

##Demonstration

Bitcoin-S has a RPC client built in. Bitcoin uses a separate program for RPCs. Starting a server uses bitcoind, RPCs use bitcoin-cli.

In a Scala console, import the file and create a new ScalaRPCClient instance. The sendCommand method will take official bitcoin RPCs and return their result. In this example, we create an RPC tool for the bitcoin test network and get the block count.

scala> import org.scalacoin.rpc.ScalaRPCClient
import org.scalacoin.rpc.ScalaRPCClient

scala> val testNet = new ScalaRPCClient("bitcoin-cli","-testnet")
testNet: org.scalacoin.rpc.ScalaRPCClient = org.scalacoin.rpc.ScalaRPCClient@106ca0dc

scala> testNet.sendCommand("getblockcount")
res8: String = "651604"

We've also predefined some RPCS to return parsed JSON values to easily interact with the data objects:

getBlockCount
getBestBlockHash
getBlockChainInfo
getMiningInfo
getNetworkInfo
getMemPoolInfo
getPeerInfo
getTxOutSetInfo
getWalletInfo
getDifficulty
getNewAddress
getRawChangeAddress
getBalance

To demonstrate since it's a small object, let's get the memory pool info. Returning MemPoolInfo using sendCommand will return the value as a string. We can also use our getMemPoolInfo RPC to return it as JSON values, which we can be used to handle the metadata inside the JSON objects:

scala> testNet.sendCommand("getmempoolinfo")
res10: String =
"{
    "size" : 2,
    "bytes" : 475
}
"

scala> testNet.getMemPoolInfo
res11: org.scalacoin.protocol.blockchain.MemPoolInfo = MemPoolInfoImpl(2,475)

scala> testNet.getMemPoolInfo.size
res12: Int = 2

scala> testNet.getMemPoolInfo.bytes
res13: Int = 475

scala> testNet.stop
res14: String = "Bitcoin server stopping"