Implemented possibility for configuring traffic splitting, and fallback using aggregate cluster #292

Author: nastassia-dailidava

envoy-control-core/src/main/kotlin/pl/allegro/tech/servicemesh/envoycontrol/snapshot/resource/clusters/EnvoyClustersFactory.kt

@@ -222,7 +222,6 @@ class EnvoyClustersFactory(
                         clusters[it],
                         globalSnapshot.endpoints[it]
                     )
-
                 }
             }
         }
@@ -283,10 +282,9 @@ class EnvoyClustersFactory(
         clusterLoadAssignment: ClusterLoadAssignment?
     ): Boolean {
         val trafficSplitting = properties.loadBalancing.trafficSplitting
-        val trafficSplitEnabled = trafficSplitting.serviceByWeightsProperties.keys.contains(serviceName)
-            && dependencies.contains(clusterName)
-        val hasEndpointsInZone = clusterLoadAssignment
-            ?.endpointsList
+        val trafficSplitEnabled = trafficSplitting.serviceByWeightsProperties.keys.contains(serviceName) &&
+            dependencies.contains(clusterName)
+        val hasEndpointsInZone = clusterLoadAssignment?.endpointsList
             ?.any { e -> trafficSplitting.zoneName == e.locality.zone } ?: false
         return trafficSplitEnabled && hasEndpointsInZone
     }

envoy-control-tests/src/main/kotlin/pl/allegro/tech/servicemesh/envoycontrol/trafficsplitting/AggregateClusterFallbackTest.kt

@@ -1,4 +1,5 @@
-import TrafficSplittingConstants.upstreamServiceName
+import TrafficSplitting.deltaPercentage
+import TrafficSplitting.upstreamServiceName
 import org.assertj.core.api.Assertions
 import org.assertj.core.data.Percentage
 import pl.allegro.tech.servicemesh.envoycontrol.assertions.isFrom
@@ -8,9 +9,10 @@ import pl.allegro.tech.servicemesh.envoycontrol.config.envoy.CallStats
 import pl.allegro.tech.servicemesh.envoycontrol.config.envoy.EnvoyExtension
 import pl.allegro.tech.servicemesh.envoycontrol.config.service.EchoServiceExtension
 
-internal object TrafficSplittingConstants {
+internal object TrafficSplitting {
     const val upstreamServiceName = "service-1"
     const val serviceName = "echo2"
+    const val deltaPercentage = 20.0
 }
 
 fun EnvoyExtension.verifyIsReachable(echoServiceExtension: EchoServiceExtension, service: String) {
@@ -22,7 +24,7 @@ fun EnvoyExtension.verifyIsReachable(echoServiceExtension: EchoServiceExtension,
 }
 
 fun CallStats.verifyCallsCountCloseTo(service: EchoServiceExtension, expectedCount: Int): CallStats {
-    Assertions.assertThat(this.hits(service)).isCloseTo(expectedCount, Percentage.withPercentage(20.0))
+    Assertions.assertThat(this.hits(service)).isCloseTo(expectedCount, Percentage.withPercentage(deltaPercentage))
     return this
 }
 
@@ -31,13 +33,6 @@ fun CallStats.verifyCallsCountGreaterThan(service: EchoServiceExtension, hits: I
     return this
 }
 
-fun CallStats.verifyNoCalls(vararg services: EchoServiceExtension): CallStats {
-    services.forEach {
-        Assertions.assertThat(this.hits(it)).isEqualTo(0)
-    }
-    return this
-}
-
 fun EnvoyExtension.callUpstreamServiceRepeatedly(
     vararg services: EchoServiceExtension,
     numberOfCalls: Int = 100,

envoy-control-tests/src/main/kotlin/pl/allegro/tech/servicemesh/envoycontrol/trafficsplitting/TrafficSplittingTestUtils.kt renamed to envoy-control-tests/src/main/kotlin/pl/allegro/tech/servicemesh/envoycontrol/trafficsplitting/TrafficSplitting.kt

@@ -1,7 +1,7 @@
 package pl.allegro.tech.servicemesh.envoycontrol.trafficsplitting
 
-import TrafficSplittingConstants.serviceName
-import TrafficSplittingConstants.upstreamServiceName
+import TrafficSplitting.serviceName
+import TrafficSplitting.upstreamServiceName
 import callUpstreamServiceRepeatedly
 import org.junit.jupiter.api.Test
 import org.junit.jupiter.api.extension.RegisterExtension
@@ -97,6 +97,4 @@ class WeightedClustersRoutingTest {
             .verifyCallsCountCloseTo(upstreamServiceDC1, 90)
             .verifyCallsCountGreaterThan(upstreamServiceDC2, 1)
     }
-
 }
-