Apache Spark shortest job scala - scala

Question

I am new to Apache Spark and scala programming. I am writing a code in scala using apache spark api docs. My goal is to create a graph and deploy objects and compute shortest path.I have written a program to generate a csv file of object which I want to use. It consists of vehicleID,source,Destination.
It is as follows:
[My sample csv file][1]
[1]: https://i.stack.imgur.com/KtSVz.png
My code to generate CSV file
import java.io.BufferedWriter
import java.io.FileWriter
import scala.collection.JavaConverters._
import scala.collection.mutable.ListBuffer
import scala.util.Random
import au.com.bytecode.opencsv.CSVWriter
import scala.collection.mutable
class MakeCSV() {
def csvBuilder(dx:Int){
val outputfile= new BufferedWriter(new FileWriter("vehicles.csv"))
val csvWriter= new CSVWriter(outputfile)
val csvFields= Array("Vehicle-id","Source","Destination")
val vehicleID=(0 to dx).toList
val sourceList=mutable.MutableList[String]()
val destinationList=mutable.MutableList[String]()
var i,sx,sy,dsx,dsy=0
for(i<-0 to dx){
sx=Random.nextInt(dx)
sy=Random.nextInt(dx)
dsx=Random.nextInt(dx)
dsy=Random.nextInt(dx)
sourceList.+=((sx,sy).toString())
destinationList.+=((dsx,dsy).toString())
}
var listOfRecords = new ListBuffer[Array[String]]()
listOfRecords += csvFields
for (i<- 0 to dx){
listOfRecords+=Array(i.toString,sourceList(Random.nextInt(sourceList.length)),destinationList(Random.nextInt(destinationList.length)))
}
csvWriter.writeAll(listOfRecords.asJava)
csvWriter.close()
}
}
My main file:
import java.io.PrintWriter
import scala.io.StdIn
import org.apache.spark.SparkContext
import org.apache.spark.SparkConf
import org.apache.spark.graphx.Graph
import org.apache.spark.graphx.util.GraphGenerators
object MainFile {
def main(args:Array[String]):Unit={
// Vehicle CSV file Generation
println("Enter the number of cars")
val input=StdIn.readInt()
val makecsv= new MakeCSV()
makecsv.csvBuilder(input)
// Spark Job Configuration
val conf = new SparkConf().setAppName("DjikstraShortestPath")
val sc= new SparkContext(conf)
// Graph Generation
println("Enter the number of rows for grid")
val row= StdIn.readInt()
println("Enter the number of columns for grid")
val column = StdIn.readInt()
val graph:Graph[(Int, Int), Double]=GraphGenerators.gridGraph(sc,row,column)
// Vehicle File opening
// For each Vehicle compute shortest path using source destination in csv file
}
}
Now I want to open that csv file and using its source and destination I want to compute shortest path for each vehicle using the graph generated above. Can anyone help me? How to open the csv file read it and find shortest path