StackProfiler.scala

/**
  * Created by adam on 31/05/17.
  */
package profiler
import scala.collection.mutable
import com.github.nscala_time.time.Imports._

class CheckPoint(val checkpointName: String, val startTime:  org.joda.time.DateTime) {}

// NOT THREADSAFE
class StackProfiler(val name: String) {

  val tStack : mutable.Stack[CheckPoint] = new mutable.Stack[CheckPoint]()

  def pushCheckpoint(checkpointName: String) : Unit ={
    // get the time of pushing
    val now = org.joda.time.DateTime.now
    // push that time and the checkpoint name onto the stack
    tStack.push(new CheckPoint(checkpointName, now))
    println(s"Starting task: ${name}-${checkpointName}")
  }

  def logProgress() : Unit = {
    // get the top of the stack, and log a "progress report"
    val currentCP = tStack.top
    val progress = (currentCP.startTime to DateTime.now).millis
    println(s"PROGRESS: ('${name}-${currentCP.checkpointName}', ${progress}, 'progress')")
  }

  def popCheckpoint() : Unit = {
    val currentCP = tStack.pop()
    val progress = (currentCP.startTime to DateTime.now).millis
    println(s"TASK_RESULT: ('${name}-${currentCP.checkpointName}', ${progress}, 'result')")
  }

  def profile[T](name: String,f: () => T) : T = {
    pushCheckpoint(name)
    val r: T = f()
    popCheckpoint()
    r
  }
}