Doobie Nested Queries

Doobie Nested Queries

selectEventOnlyFutureTarget(id: String, guid: String, timestamp: LocalDateTime, limit: Int): Process[ConnectionIO, Target]
selectEventOnlyPastTarget(id: String, guid: String, timestamp: LocalDateTime, limit: Int): Process[ConnectionIO, Target]
getSubTarget1(id: String, guid: String): ConnectionIO[List[SubTarget1]]
getSubTarget2(ooid: String, guid: String): Process[ConnectionIO, SubTarget2]
getSubTarget3(ooid: String, guid: String): Process[ConnectionIO, SubTarget3]

val statements = List[ConnectionIO[List[Target]]](
	selectEventOnlyFutureTarget(id, guid, timestamp, futureLimit).list,
	selectEventOnlyPastTarget(id, guid, timestamp, pastLimit).list
)
	
val targets: ConnectionIO[List[Target]] 		= for {
	    	tlss 		<- 	statements.sequenceU
	    	tlssf 		<- 	tlss.flatten.point[ConnectionIO]
	    	tls 		<-      tlssf.traverse(tl => {
	    						val st1 = getSubTarget1(id, tl.guid).transact(xa).run
	    						val st2 = getSubTarget2(id, tl.guid).list.transact(xa).run
	    						val st2 = getSubTarget3(id, tl.guid).list.transact(xa).run
	    						tl.copy(subtarget1 	= st1,
				                    	        subtarget2      = if (!st2.isEmpty) Option(lks) else None,
				                    		subtarget3      = if (!st2.isEmpty) Option(mtg) else None
				                       ).point[ConnectionIO]
	    					})
	    } yield {
    		tls
	    }
	    
val result: List[Target] 	= targets.transact(xa).run

result