Added throttling to reduce Bamboo peak load and number of concurrent connections

app/services/VulnerabilityNotificationService.scala

@@ -14,21 +14,6 @@ import slick.jdbc.TransactionIsolation
 
 import scala.concurrent.{ExecutionContext, Future}
 
-final class SingleFutureExecutionThrottler() (implicit executionContext: ExecutionContext){
-  private var nextFuture: Future[_] = Future.successful(null)
-
-  def throttle[T](f: => Future[T]): Future[T] = synchronized{
-    val newFuture = nextFuture.recover{ case _ => null}.flatMap(_ => f)
-    nextFuture = newFuture
-    newFuture
-  }
-
-}
-
-final class NoThrottler() (implicit executionContext: ExecutionContext){
-  def throttle[T](f: => Future[T]): Future[T] = f
-}
-
 class VulnerabilityNotificationService @Inject() (protected val dbConfigProvider: DatabaseConfigProvider)(implicit executionContext: ExecutionContext) extends HasDatabaseConfigProvider[models.profile.type]{
   import dbConfig.driver.api._
   import models.tables._

app/services/throttlers.scala

@@ -0,0 +1,22 @@
+package services
+
+import scala.concurrent.{ExecutionContext, Future}
+
+trait Throttler {
+  def throttle[T](f: => Future[T]): Future[T]
+}
+
+final class SingleFutureExecutionThrottler() (implicit executionContext: ExecutionContext) extends Throttler{
+  private var nextFuture: Future[_] = Future.successful(null)
+
+  def throttle[T](f: => Future[T]): Future[T] = synchronized{
+    val newFuture = nextFuture.recover{ case _ => null}.flatMap(_ => f)
+    nextFuture = newFuture
+    newFuture
+  }
+
+}
+
+final class NoThrottler() (implicit executionContext: ExecutionContext) extends Throttler{
+  def throttle[T](f: => Future[T]): Future[T] = f
+}