multinode.go

// ensureTopologyRequirements sets nodeSelection affinity according to given topology keys for drivers that provide them.
// If no node with the given topology key is found, this function will skip the test directly.
func ensureTopologyRequirements(nodeSelection *e2epod.NodeSelection, cs clientset.Interface, topologyKeys []string, minCount int) error {
	nodes, err := e2enode.GetReadySchedulableNodes(cs)
	if err != nil {
		return err
	}

	// Get the number of nodes per zone per topology key.
	// Example: map["topology.ebs.csi.aws.com/zone"]["us-east-1"] = 2
	topologyCount := map[string]map[string]int{}
	for _, node := range nodes.Items {
		for _, topologyKey := range topologyKeys {
			if zone, ok := node.Labels[topologyKey]; ok {
				if _, ok := topologyCount[topologyKey]; !ok {
					topologyCount[topologyKey] = make(map[string]int)
				}
				topologyCount[topologyKey][zone]++
			}
		}
	}

	// Once we find a topology with at least minCount of nodes, we use it in the tests
	for topologyKey, zoneCount := range topologyCount {
		for zone, count := range zoneCount {
			if count >= minCount {
				e2epod.SetNodeAffinityTopologyRequirement(nodeSelection, topology{topologyKey: zone})
				return nil
			}
		}
	}

	framework.Skipf("No topology with at least %d nodes found - skipping", minCount)
	return nil
}