fix: adding retry delay for customers in sleepingBarber (#38)

Author: AlexZangerle

sleepingBarber/src/main/kotlin/ac/at/uibk/dps/dapr/barber/customer/CustomerActorImpl.kt

@@ -6,7 +6,9 @@ import io.dapr.actors.runtime.AbstractActor
 import io.dapr.actors.runtime.ActorRuntimeContext
 import io.dapr.client.DaprClient
 import io.dapr.client.DaprClientBuilder
+import java.security.SecureRandom
 import java.util.concurrent.TimeUnit
+import kotlin.random.Random
 import kotlin.time.Clock
 
 class CustomerActorImpl(runtimeContext: ActorRuntimeContext<CustomerActorImpl>, id: ActorId) :
@@ -15,6 +17,14 @@ class CustomerActorImpl(runtimeContext: ActorRuntimeContext<CustomerActorImpl>,
 
   val client: DaprClient? = DaprClientBuilder().build()
 
+  private val seedGenerator = SecureRandom()
+  private val threadRng =
+    object : ThreadLocal<Random>() {
+      override fun initialValue(): Random {
+        return Random(seedGenerator.nextLong())
+      }
+    }
+
   var count = 0
 
   override fun request() {
@@ -23,6 +33,7 @@ class CustomerActorImpl(runtimeContext: ActorRuntimeContext<CustomerActorImpl>,
 
   override fun full(data: Map<String, Any>) {
     measureEventTime(data)
+    Thread.sleep(randomAround(10, 2).toLong())
     request()
   }
 
@@ -53,4 +64,8 @@ class CustomerActorImpl(runtimeContext: ActorRuntimeContext<CustomerActorImpl>,
       .timer("event.latency")!!
       .update((deltaNanos), TimeUnit.NANOSECONDS)
   }
+
+  private fun randomAround(base: Int, delta: Int): Int {
+    return (base - delta..base + delta).random(threadRng.get())
+  }
 }