refactor: env record trigger into odigos CRD

odiglet/pkg/kube/runtime_details/workload_enabled_predicated.go

@@ -39,38 +39,30 @@ func (i *WorkloadEnabledPredicate) Update(e event.UpdateEvent) bool {
 	newEnabled := isInstrumentationEnabled(e.ObjectNew)
 	becameEnabled := !oldEnabled && newEnabled
 
-	switch e.ObjectNew.GetObjectKind().GroupVersionKind().Kind {
-	case "Deployment":
-		oldDeployment, oldOk := e.ObjectOld.(*appsv1.Deployment)
-		newDeployment, newOk := e.ObjectNew.(*appsv1.Deployment)
-		if oldOk && newOk {
-			hadAvailableReplicas := isDeploymentAvailableReplicas(oldDeployment)
-			hasAvailableReplicas := isDeploymentAvailableReplicas(newDeployment)
-			replicasBecameAvailable := !hadAvailableReplicas && hasAvailableReplicas
-			return becameEnabled || replicasBecameAvailable
-		}
-	case "DaemonSet":
-		oldDaemonSet, oldOk := e.ObjectOld.(*appsv1.DaemonSet)
-		newDaemonSet, newOk := e.ObjectNew.(*appsv1.DaemonSet)
-		if oldOk && newOk {
-			hadAvailableReplicas := isDaemonsetAvailableReplicas(oldDaemonSet)
-			hasAvailableReplicas := isDaemonsetAvailableReplicas(newDaemonSet)
-			replicasBecameAvailable := !hadAvailableReplicas && hasAvailableReplicas
-			return becameEnabled || replicasBecameAvailable
-		}
-	case "StatefulSet":
-		oldStatefulSet, oldOk := e.ObjectOld.(*appsv1.StatefulSet)
-		newStatefulSet, newOk := e.ObjectNew.(*appsv1.StatefulSet)
-		if oldOk && newOk {
-			hadAvailableReplicas := isStatefulsetAvailableReplicas(oldStatefulSet)
-			hasAvailableReplicas := isStatefulsetAvailableReplicas(newStatefulSet)
-			replicasBecameAvailable := !hadAvailableReplicas && hasAvailableReplicas
-			return becameEnabled || replicasBecameAvailable
-		}
+	if becameEnabled {
+		return true
 	}
 
-	// for namespace events or if there was issue with type casting
-	return becameEnabled
+	replicasBecameAvailable := didReplicasBecomeAvailable(e.ObjectOld, e.ObjectNew)
+	if replicasBecameAvailable {
+		return true
+	}
+
+	// The language detection process currently does 2 things:
+	// 1. Detect the language of each container in the workload
+	// 2. Detect the actual value of relevant environment variables for each container.
+	//
+	// thus, we need to re-run language detection if something that might affect
+	// any of these 2 things has changed.
+	//
+	// currently, we only check if the enabled label has changed, or the pod become available,
+	// but other events that might affect the language detection are not checked.
+	// for example: if the container array changed, if an env var was added/removed, if the image was changed, etc.
+	// we might need to add these checks in the future.
+	// notice that the change alone is not enough - after the change, the workload running pods still
+	// run an old manifest. we should re-calculate the runtime details only with up-to-date running pods.
+
+	return false
 }
 
 func (i *WorkloadEnabledPredicate) Delete(e event.DeleteEvent) bool {
@@ -102,3 +94,25 @@ func isDaemonsetAvailableReplicas(dep *appsv1.DaemonSet) bool {
 func isStatefulsetAvailableReplicas(dep *appsv1.StatefulSet) bool {
 	return dep.Status.ReadyReplicas > 0
 }
+
+// language detection relies on the fact that the workload has available replicas.
+// if we did not have available replicas before, and now we do, we need to re-run language detection
+func didReplicasBecomeAvailable(old client.Object, new client.Object) bool {
+
+	switch new.(type) {
+	case *appsv1.Deployment:
+		hadAvailableReplicas := isDeploymentAvailableReplicas(new.(*appsv1.Deployment))
+		hasAvailableReplicas := isDeploymentAvailableReplicas(old.(*appsv1.Deployment))
+		return !hadAvailableReplicas && hasAvailableReplicas
+	case *appsv1.DaemonSet:
+		hadAvailableReplicas := isDaemonsetAvailableReplicas(new.(*appsv1.DaemonSet))
+		hasAvailableReplicas := isDaemonsetAvailableReplicas(old.(*appsv1.DaemonSet))
+		return !hadAvailableReplicas && hasAvailableReplicas
+	case *appsv1.StatefulSet:
+		hadAvailableReplicas := isStatefulsetAvailableReplicas(new.(*appsv1.StatefulSet))
+		hasAvailableReplicas := isStatefulsetAvailableReplicas(old.(*appsv1.StatefulSet))
+		return !hadAvailableReplicas && hasAvailableReplicas
+	}
+
+	return false
+}