Stellar SDK for Scala

The Scala SDK for the Stellar network provides an API to:

• Create accounts
• Build and submit transactions
• Query network state from Horizon
• Stream network updates from Horizon [Pending]
• Query federation servers [Pending]

Aims

A Scala developer would choose to use this SDK because it aims to provide:

• Convenience

  • Asynchronous by default
  • Encapsulation of paged responses into Streams
  • Case classes instead of builder patterns
  • Perform network operations on the terminal through the scala REPL

• Correctness

  • Generative testing using scalacheck with the goal of 100% test coverage
  • Options, not nulls
  • Trys, not exceptions
  • Explicit type hierarchies instead of meaningful primitives

Deprecation warning

At this stage, some classes and interfaces are likely to be refined. Minor releases may break backwards compatibility with minimal notice until v1.0.0.

Installation

In your build.sbt

resolvers += "scala-stellar-sdk-repo" at "https://dl.bintray.com/synesso/mvn"

libraryDependencies +=  "stellar.scala.sdk" %% "scala-stellar-sdk" % "0.1.2.1"

Examples

The following examples use the Ammonite REPL. After launching amm, fetch and import the Stellar SDK for Scala.

interp.repositories() ++= Seq(coursier.MavenRepository("https://dl.bintray.com/synesso/mvn/"))

import $ivy.`stellar.scala.sdk::scala-stellar-sdk:0.1.2.1`
import scala.concurrent.ExecutionContext.Implicits.global
import scala.concurrent._
import stellar.sdk._
import stellar.sdk.op._
import stellar.sdk.resp._

Creating and funding a test account

val kp = KeyPair.random
TestNetwork.fund(kp)

Checking the status of an account

import scala.util.Success

TestNetwork.account(kp) onSuccess { case resp =>
  println(s"""
    |Account ${resp.id}
    |  Last sequence was ${resp.lastSequence}.
    |  Balances: ${resp.balances.mkString(",")}
    """.stripMargin)
}

Funding a new account with a create account operation

implicit val network = TestNetwork

val funder: KeyPair = kp // funded account from first example
val toCreate = KeyPair.random

for {
  account <- TestNetwork.account(funder)
  txn <- Future.fromTry {
    Transaction(Account(funder, account.lastSequence + 1))
      .add(CreateAccountOperation(toCreate, Amount.lumens(1)))
      .sign(funder)
    }
  } yield txn.submit

Additional examples can be found in the /examples folder.

Progress

Project progress & roadmap can be viewed in the projects tab.

Contributing

Contributions are warmly welcomed. See issues for features that can be worked on immediately. Or feel free to add your own features/issues to that list.

Contact

Let's chat about this on the Stellar-public Slack #dev channel. My username is @jem.