fix: error clearly if there are no nodes on the Kubernetes cluster (#…

…1553)

## Description:
An AWS EKS cluster starts with no nodes which is quite confusing for the
user if the engine doesn't start. This checks if there are any nodes and
otherwise tells the user there aren't

## Is this change user facing?
YES

## References (if applicable):
#1507

container-engine-lib/lib/backend_impls/kubernetes/kubernetes_kurtosis_backend/engine_functions/create_engine.go

@@ -42,6 +42,14 @@ func CreateEngine(
 	*engine.Engine,
 	error,
 ) {
+	hasNodes, err := kubernetesManager.HasComputeNodes(ctx)
+	if err != nil {
+		return nil, stacktrace.Propagate(err, "An error occurred while verifying whether the Kubernetes cluster has any compute nodes")
+	}
+	if !hasNodes {
+		return nil, stacktrace.NewError("Can't start engine on the Kubernetes cluster as it has no compute nodes")
+	}
+
 	engineGuidStr, err := uuid_generator.GenerateUUIDString()
 	if err != nil {
 		return nil, stacktrace.Propagate(err, "An error occurred generating a UUID string for the engine")

container-engine-lib/lib/backend_impls/kubernetes/kubernetes_manager/kubernetes_manager.go

@@ -122,6 +122,22 @@ var (
 		},
 		ResourceVersion: "",
 	}
+	globalListOptions = metav1.ListOptions{
+		TypeMeta: metav1.TypeMeta{
+			Kind:       "",
+			APIVersion: "",
+		},
+		LabelSelector:        "",
+		FieldSelector:        "",
+		Watch:                false,
+		AllowWatchBookmarks:  false,
+		ResourceVersion:      "",
+		ResourceVersionMatch: "",
+		TimeoutSeconds:       nil,
+		Limit:                0,
+		Continue:             "",
+		SendInitialEvents:    nil,
+	}
 )
 
 type KubernetesManager struct {
@@ -1729,6 +1745,14 @@ func (manager *KubernetesManager) GetExecStream(ctx context.Context, pod *apiv1.
 		})
 }
 
+func (manager *KubernetesManager) HasComputeNodes(ctx context.Context) (bool, error) {
+	nodes, err := manager.kubernetesClientSet.CoreV1().Nodes().List(ctx, globalListOptions)
+	if err != nil {
+		return false, stacktrace.Propagate(err, "An error occurred while checking if the Kubernetes cluster has any nodes")
+	}
+	return len(nodes.Items) != 0, nil
+}
+
 // TODO Delete this after 2022-08-01 if we're not using Jobs
 /*
 func (manager *KubernetesManager) CreateJobWithContainerAndVolume(ctx context.Context,