build.sbt

name := "ds"

scalaVersion := "2.11.8"

// https://mvnrepository.com/artifact/com.google.cloud/google-cloud-datastore
libraryDependencies += "com.google.cloud" % "google-cloud-datastore" % "0.6.0"

Main.scala

import com.google.cloud.datastore._
import com.google.cloud.datastore.testing._

object Main extends App {

  def benchmark[A](title: String)(f: => A): A = {
    val t0   = System.currentTimeMillis()
    val o: A = f
    val t1   = System.currentTimeMillis()
    println(title)
    println("-----")
    println(s"  - duration: ${t1 - t0}ms")
    println(s"  - returned: $o")
    println("-----")
    println("")
    o
  }

  val ds = benchmark("get a service instance") {
    DatastoreOptions.getDefaultInstance().getService()
  }

  val keyFactory = benchmark("create a key factory") {
    ds.newKeyFactory().kind("Room")
  }

  val key = benchmark("create a key") {
    ds.allocateId(keyFactory.newKey())
  }

  val entity = Entity
    .builder(key)
    .set("title", StringValue.builder("untitled").build())
    .set("createdAt", DateTime.now())
    .set("updatedAt", DateTime.now())
    .build()

  benchmark("put an entity") {
    ds.put(entity)
  }

  val key1 = ds.newKeyFactory().setKind("Session").newKey(5629499534213120L)
  benchmark("get an entity by a key: 5629499534213120") {
    ds.get(key1, Array[ReadOption]() :_*)
  }

  val key2 = ds.newKeyFactory().setKind("Session").newKey(5649391675244544L)
  benchmark("get an entity by a key: 5649391675244544") {
    ds.get(key2, Array[ReadOption]() :_*)
  }

}