RunWithContextEntrySample.scala

//
// Sample code snipppet to describe lack of dryness in my current approach
// Goal is to make `correlationId` available as a context entry for all the routes
//

// uuid generator
object IdGenerator {
  def newId: String = UUID.randomUUID.toString
}

// create correlationKey
object CorrelationIdCodec {
  val correlationKey = Context.key[String]("correlationId", null) 
}

class MyService {
  // entity 1
  def createEntity(js: Json): Future[Option[Js] = ???
  def getEntity(id: String): Future[Option[Js] = ???
  
  // entity 2
  def createEntity2(js: Json): Future[Option[Js] = ???
  def getEntity2(id: String): Future[Option[Js] = ???
}

object MyService {
  def myService = new MyService()
}

import MyService.myService

// sample routes
val someCrudApi: Route =
  (pathPrefix("path1" / "path2")) {
    (post & entity(as[Json]) ) { js =>
      Kamon.runWithContextEntry(CorrelationIdCodec.correlationKey, IdGenerator.newId) {
        onSuccess(myService.createEntity(js))
      }
     } ~
     (get & path(Segment)) { attribute1 =>
        Kamon.runWithContextEntry(CorrelationIdCodec.correlationKey, IdGenerator.newId) {
          onSuccess(myService.getEntity(attribute1))      
        }
    } // end `pathPrefix`
    
val someCrudApi2: Route =
  (pathPrefix("path3" / "path4") & myCustomAuthDirective) {
    (post & entity(as[Json]) ) { js =>
      Kamon.runWithContextEntry(CorrelationIdCodec.correlationKey, IdGenerator.newId) {
        onSuccess(myService.createEntity2(js))
      }
     } ~
     (get & path(Segment)) { attribute1 =>
        Kamon.runWithContextEntry(CorrelationIdCodec.correlationKey, IdGenerator.newId) {
          onSuccess(myService.getEntity2(attribute1))      
        }
    } // end `pathPrefix`