add per min throttling support to fpc

common/scala/src/main/scala/org/apache/openwhisk/core/WhiskConfig.scala

@@ -203,6 +203,7 @@ object WhiskConfig {
 object ConfigKeys {
   val cluster = "whisk.cluster"
   val loadbalancer = "whisk.loadbalancer"
+  val fpcLoadBalancer = "whisk.loadbalancer.fpc"
   val fraction = "whisk.fraction"
   val buildInformation = "whisk.info"
 

core/controller/src/main/resources/reference.conf

@@ -29,6 +29,10 @@ whisk {
     # extra time to increase the timeout for forced active acks
     # default is 1.minute
     timeout-addon = 1m
+
+    fpc {
+      use-perMin-throttles = false
+    }
   }
   controller {
     protocol: http

core/controller/src/main/scala/org/apache/openwhisk/core/entitlement/Entitlement.scala

@@ -360,7 +360,7 @@ protected[core] abstract class EntitlementProvider(
    * @param resources the set of resources must contain at least one resource that can be activated else return None
    * @return future completing successfully if user is below limits else failing with a rejection
    */
-  private def checkUserThrottle(user: Identity, right: Privilege, resources: Set[Resource])(
+  protected[core] def checkUserThrottle(user: Identity, right: Privilege, resources: Set[Resource])(
     implicit transid: TransactionId): Future[Unit] = {
     if (right == ACTIVATE) {
       if (resources.exists(_.collection.path == Collection.ACTIONS)) {

core/controller/src/main/scala/org/apache/openwhisk/core/entitlement/FPCEntitlement.scala

@@ -21,20 +21,38 @@ import scala.concurrent.Future
 import akka.actor.ActorSystem
 import akka.http.scaladsl.model.StatusCodes.TooManyRequests
 import org.apache.openwhisk.common.{Logging, TransactionId, UserEvents}
-import org.apache.openwhisk.core.WhiskConfig
+import org.apache.openwhisk.core.{ConfigKeys, WhiskConfig}
 import org.apache.openwhisk.core.connector.{EventMessage, Metric}
 import org.apache.openwhisk.core.controller.RejectRequest
 import org.apache.openwhisk.core.entitlement.Privilege.ACTIVATE
 import org.apache.openwhisk.core.entity.{ControllerInstanceId, Identity}
 import org.apache.openwhisk.core.loadBalancer.LoadBalancer
+import pureconfig.loadConfigOrThrow
+import pureconfig.generic.auto._
+
+case class FPCEntitlementConfig(usePerMinThrottles: Boolean)
 
 protected[core] class FPCEntitlementProvider(
   private val config: WhiskConfig,
   private val loadBalancer: LoadBalancer,
   private val controllerInstance: ControllerInstanceId)(implicit actorSystem: ActorSystem, logging: Logging)
     extends LocalEntitlementProvider(config, loadBalancer, controllerInstance) {
 
+  private implicit val executionContext = actorSystem.dispatcher
+
+  private val fpcEntitlementConfig: FPCEntitlementConfig =
+    loadConfigOrThrow[FPCEntitlementConfig](ConfigKeys.fpcLoadBalancer)
+
   override protected[core] def checkThrottles(user: Identity, right: Privilege, resources: Set[Resource])(
+    implicit transid: TransactionId): Future[Unit] = {
+    if (fpcEntitlementConfig.usePerMinThrottles) {
+      checkUserThrottle(user, right, resources).flatMap(_ => checkFPCConcurrentThrottle(user, right, resources))
+    } else {
+      checkFPCConcurrentThrottle(user, right, resources)
+    }
+  }
+
+  private def checkFPCConcurrentThrottle(user: Identity, right: Privilege, resources: Set[Resource])(
     implicit transid: TransactionId): Future[Unit] = {
     if (right == ACTIVATE) {
       val checks = resources.filter(_.collection.path == Collection.ACTIONS).map { res =>
@@ -55,7 +73,6 @@ protected[core] class FPCEntitlementProvider(
       } else Future.successful(())
     } else Future.successful(())
   }
-
 }
 
 private object FPCEntitlementProvider extends EntitlementSpiProvider {

core/controller/src/main/scala/org/apache/openwhisk/core/loadBalancer/FPCPoolBalancer.scala

@@ -34,6 +34,8 @@ import scala.concurrent.{ExecutionContext, ExecutionContextExecutor, Future, Pro
 import scala.language.postfixOps
 import scala.util.{Failure, Random, Success, Try}
 
+case class FPCPoolBalancerConfig(usePerMinThrottle: Boolean)
+
 class FPCPoolBalancer(config: WhiskConfig,
                       controllerInstance: ControllerInstanceId,
                       etcdClient: EtcdClient,