# Lottery Phase II

# Lottery Domain Module

# 'Create Lottery' Command

Add a domain module in Lottery.ksmile

domain-module LotteryDomain at com.metastay.lotterydomain

$smile
Refresh Eclipse to see LotteryDomain.kdomain
Add Lottery.create Command in LotteryDomain.kdomain

domain-logic Lottery {
    function lotteryNameExists(lotteryName:String):Boolean
}
  
command-set Lottery {
    domain-logic-ref lottery:Lottery
    command create {
        input(lotteryName:String, amount:Int)
        pre {
            condition NewLotteryName => !(lottery.lotteryNameExists(input.lotteryName)) failing "Lottery name already exists!"
        }
    }
}

$compile
Open LotteryCommandSetCode to save it to implement.

WARNING

LotteryWriter and other mongo related files not available to implement because LotteryDomain is not dependent on LotteryMongo.

Add the LotteryMongo dependency in LotteryDomain in Lottery.ksmile file

section Lottery {
    data-module LotteryData at com.metastay.lottery
    mongo-module LotteryMongo at com.metastay.lotterymongo
    domain-module LotteryDomain(LotteryMongo) at com.metastay.lotterydomain
    play-module LotteryPlay(LotteryData, LotteryMongo) at lotteryplay
}

$smile
Open LotteryCommandSetCode to implement create command as below.

override def create = CreateCommand {
    import CreateCommand._;
    input: Input =>
    LotteryWriter().save(LotteryRow(lotteryName = input.lotteryName, amount = input.amount, open = false))
}

Open LotteryDomainLogicCode to implement lotteryNameExists method as below

override def lotteryNameExists (lotteryName:String):Boolean = LotteryQuery().lotteryName.is(lotteryName).exists

$compile
Write test in LotteryDomainTestSuite as below.

test("create", Tag("create")) {
    val lotteryCommandSet= grab[LotteryCommandSet]
    lotteryCommandSet.createNow("WBLoto", 20000).println;
}

$project LotteryDomain
$testOnly com.metastay.lotterydomain.LotteryDomainTestSuite -- -n create
Check in DB if the WBLoto Lottery has been created

# 'Add Participant' And 'Run'Command

Adding two more commands to LotteryDomain.kdomain

domain-logic Lottery {
    function lotteryNameExists(lotteryName:String):Boolean
    function participantExist(lotteryName:String, participantName:String):Boolean
    function participantCount(lotteryName:String):Int
}
  
command-set Lottery {
    domain-logic-ref lottery:Lottery
    command create {
        input(lotteryName:String, amount:Int)
        pre {
            condition NewLotteryName => !(lottery.lotteryNameExists(input.lotteryName)) failing "Lottery name already exists!"
        }
    }
     
    command addParticipant {
        input(lotteryName:String, participantName:String)
        pre {
            condition lotteryMustExists "Lottery must exist" => lottery.lotteryNameExists(input.lotteryName)
            condition particpantNotYetAdded "Participant Not yet added" => 
                !lottery.participantExist(input.lotteryName, input.participantName)
             
        }
    }
     
    command run {
        input(lotteryName:String)
        pre {
            condition ExistingLotteryName => lottery.lotteryNameExists(input.lotteryName) failing "Lottery name does not exists"
            condition atLeastTwoParticipants => 
                ExistingLotteryName -> `domainLogicRef.lottery.participantCount(input.lotteryName) > 1` 
                failing "The lottery does not have any participant!"            
        }
        output(winner:String)
    }
     
}

$compile
Implementing addParticipant() and run() in LotteryCommandSetCode

class LotteryCommandSetCode(domainRef: DomainRef) extends LotteryCommandSetCommands {         
  override def create = CreateCommand {
    import CreateCommand._;
    input: Input =>
      LotteryWriter().save(LotteryRow(lotteryName = input.lotteryName, amount = input.amount))
  }     
 
  override def addParticipant = AddParticipantCommand {
    import AddParticipantCommand._;
    input: Input =>
      val q = LotteryQuery().lotteryName.is(input.lotteryName)
      val u = LotteryUpdate().participantList.addToSet(input.participantName)
      LotteryWriter().updateOne(q, u)
 
  }
 
  override def run = RunCommand {
    import RunCommand._;
    input: Input =>
      val q = LotteryQuery().lotteryName.is(input.lotteryName)
      val participantList = q.findOne.get.participantList //To find the participantList
      val winnerIndex = scala.util.Random.nextInt(participantList.size) //To find a winner Index
      val winner = participantList(winnerIndex)
      val u = LotteryUpdate().winner.set(Some(winner)).open.set(false)
      LotteryWriter().updateOne(q, u)
      Output(winner)
  }         
}

Implementing participantExist() and participantCount() in LotteryDomainCode

override def lotteryNameExists (lotteryName:String):Boolean = 
    LotteryQuery().lotteryName.equalsIgnoreCase(lotteryName).exists

override def participantExist(lotteryName: String, participantName: String): Boolean =  
    LotteryQuery().lotteryName.is(lotteryName).participantList.contains(participantName).exists

override def participantCount(lotteryName: String): Int = 
    LotteryQuery().lotteryName.is(lotteryName).findOne.get.participantList.size

Add test for addParticipant and run in RunCommandTestSuite
$project LoteryDomain
$testOnly com.metastay.lotterydomain.commandset.lottery.RunCommandTestSuite -- -n run

# Integrate Play and Domain

Adding all the validations and checks which are available in domain to the rest api.
Add LotteryDomain as a dependency to LotteryPlay Module rather than LotteryMongo in Lottery.ksmile

domain-module LotteryDomain(LotteryMongo) at com.metastay.lotterydomain
play-module LotteryPlay(LotteryData, LotteryDomain) at lotteryplay

$smile
Replace the actions by command-action to link it to command in LotteryPlay.kplay

web-writer Lottery {
    command-action createLottery(POST) LotteryDomain::Lottery.create
    command-action addParticipant(POST) LotteryDomain::Lottery.addParticipant
    command-action run(POST) LotteryDomain::Lottery.run
}

$compile
Delete the LotteryWebWriterCode.scala as its not more needed.
$compile
test through curl
- curl -H "Content-Type: application/json" -X POST -d '{"lotteryName":"Loto","amount":1000}' http://localhost:9000/api/lottery/create-lottery
- curl -H "Content-Type: application/json" -X POST -d '{"lotteryName":"Loto","participantName":"John"}' http://localhost:9000/api/lottery/add-participant
- curl -H "Content-Type: application/json" -X POST -d '{"lotteryName":"Loto","participantName":"Jim"}' http://localhost:9000/api/lottery/add-participant
- curl -H "Content-Type: application/json" -X POST -d '{"lotteryName":"Loto","participantName":"Joe"}' http://localhost:9000/api/lottery/add-participant
- curl -H "Content-Type: application/json" -X POST -d '{"lotteryName":"Loto"}' http://localhost:9000/api/lottery/run

# Enhancement

Add a pre to the command run, that if the lottery is closed than it cannot run.
Add another function to domain Lottery in LotteryDomain.kdomain

domain-logic Lottery {
    function isOpenToRun(lotteryName:String):Boolean
}

Add the pre to the run command
Change Lottery command-set under LotteryDomain.kdomain

command run {
    input(lotteryName:String)
    pre {
        condition NotYetRun => lottery.isOpenToRun(input.lotteryName) failing "it has already run!"
        condition ExistingLotteryName => 
            lottery.lotteryNameExists(input.lotteryName) failing "Lottery name does not exists"
        condition atLeastTwoParticipants => 
            ExistingLotteryName -> `domainLogicRef.lottery.participantCount(input.lotteryName) > 1` 
            failing "The lottery does not have any participant!"
    }
    output(winner:String)
}

$compile
Implement LotteryDomainLogicCode isOpenToRun

override def isOpenToRun(lotteryName: String): Boolean = LotteryQuery().lotteryName.is(lotteryName).open.is(true).exists

run and test with swagger or curl

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