vigneshwaranr

#! /bin/sh

usage_error () {
    echo 'Usage: sh migrator.sh <path to sqlite_to_postgres.py> <path to sqlite db file> <an empty dir to output dump files>'
    echo
    echo 'Example:'
    echo '>sh migrator.sh sqlite_to_postgres.py ~/reviewboard.db /tmp/dumps'
    echo
    echo 'Tested on:'
    echo 'Python 2.7.3'

vigneshwaranr

import scala.concurrent.ExecutionContext.Implicits.global
import scala.concurrent.Future

// YESS :(
someFutureJob().map { value =>
  operate(value)
}

vigneshwaranr

def send(message: Message): Future[Boolean] = {
  if (isValid(message)) {
    producer.send(message).recover({case _ => false})
  } else {
    Future.successful(false) // fixed :)
  }
}

vigneshwaranr

def send(message: Message): Future[Boolean] = {
  if (isValid(message)) {
    producer.send(message).recover({case _ => false})
  } else {
    Future(false) // this is not good
  }
}

vigneshwaranr

import scala.concurrent.ExecutionContext.Implicits.global
import scala.concurrent.{ExecutionContext, Future}

class API(cacheService: CacheService, processor: Processor) {

  def process(request: Request): Future[Response] = {
    for {
      dedupedRequest <- cacheService.isDuplicateRequest(request)
      response <- processor.process(dedupedRequest)
      _ = cacheService.setCacheForDeduplication(dedupedRequest)

vigneshwaranr

import scala.concurrent.ExecutionContext.Implicits.global
import scala.concurrent.{ExecutionContext, Future}

class API(cacheService: CacheService, processor: Processor) {

  def process(request: Request): Future[Response] = {
    for {
      dedupedRequest <- cacheService.isDuplicateRequest(request)
      response <- processor.process(dedupedRequest)
      _ = cacheService.setCacheForDeduplication(dedupedRequest) // now unplugged from the flow

vigneshwaranr

def executeOperation(): Future[Boolean] = {
  someHeavyCPUOperation()
  Future(anotherOperation())
}

vigneshwaranr

import scala.concurrent.ExecutionContext.Implicits.global
import scala.concurrent.{ExecutionContext, Future}

trait Request

trait Response

trait CacheService {
  def isDuplicateRequest(request: Request)(implicit ec: ExecutionContext): Future[Option[Request]]

vigneshwaranr

import scala.concurrent.ExecutionContext.Implicits.global
import scala.concurrent.{ExecutionContext, Future}

trait Request

trait Response

trait CacheService {
  def myOwnEc: ExecutionContext

vigneshwaranr

import scala.concurrent.ExecutionContext.Implicits.global
import scala.concurrent.Future

trait WaterSupply {
  def turnOn(): Future[Unit]
}

trait PowerPlant {
  def waterSupply: WaterSupply