cloud provider: add zone/region to InstanceMetadata

The existing Zones interface was mainly created for the kubelet
to interface with a local metadata server to fetch a node's zone
and region. With external cloud providers, it makes more sense for
the zone/region logic to be coupled to the Instances interface.
This commit adds zone/region information to the recently added
InstanceMetadata type we're using as part of the new InstancesV2
interface in the cloud provider.

Signed-off-by: Andrew Sy Kim <kim.andrewsy@gmail.com>

staging/src/k8s.io/cloud-provider/cloud.go

@@ -294,4 +294,15 @@ type InstanceMetadata struct {
 	// NodeAddress contains information for the instance's address.
 	// The node addresses returned here will be set on the node's status.addresses field.
 	NodeAddresses []v1.NodeAddress
+
+	// Zone is the zone that the instance is in.
+	// The value set here is applied as the following labels on the node:
+	//   * topology.kubernetes.io/zone=<zone>
+	//   * failure-domain.beta.kubernetes.io/zone=<zone> (DEPRECATED)
+	Zone string
+	// Region is the region that the instance is in.
+	// The value set here is applied as the following labels on the node:
+	//   * topology.kubernetes.io/region=<region>
+	//   * failure-domain.beta.kubernetes.io/region=<region> (DEPRECATED)
+	Region string
 }

staging/src/k8s.io/cloud-provider/controllers/node/node_controller.go

@@ -447,18 +447,41 @@ func (cnc *CloudNodeController) getNodeModifiersFromCloudProvider(ctx context.Co
 		if !ok {
 			return nil, fmt.Errorf("failed to get instances from cloud provider")
 		}
+
 		nodeAddresses, err := getNodeAddressesByProviderIDOrName(ctx, instances, providerID, nodeName)
 		if err != nil {
 			return nil, err
 		}
+
 		instanceType, err := getInstanceTypeByProviderIDOrName(ctx, instances, providerID, nodeName)
 		if err != nil {
 			return nil, err
 		}
-		return &cloudprovider.InstanceMetadata{
+
+		instanceMetadata := &cloudprovider.InstanceMetadata{
 			InstanceType:  instanceType,
 			NodeAddresses: nodeAddresses,
-		}, nil
+		}
+
+		zones, ok := cnc.cloud.Zones()
+		if !ok {
+			return instanceMetadata, nil
+		}
+
+		zone, err := getZoneByProviderIDOrName(ctx, zones, providerID, node.Name)
+		if err != nil {
+			return nil, fmt.Errorf("failed to get zone from cloud provider: %v", err)
+		}
+
+		if zone.FailureDomain != "" {
+			instanceMetadata.Zone = zone.FailureDomain
+		}
+
+		if zone.Region != "" {
+			instanceMetadata.Region = zone.Region
+		}
+
+		return instanceMetadata, nil
 	}
 
 	instanceMeta, err := instanceMetadataGetter(providerID, node.Name, node)
@@ -484,34 +507,29 @@ func (cnc *CloudNodeController) getNodeModifiersFromCloudProvider(ctx context.Co
 		})
 	}
 
-	if zones, ok := cnc.cloud.Zones(); ok {
+	if instanceMeta.Zone != "" {
-		zone, err := getZoneByProviderIDOrName(ctx, zones, providerID, node.Name)
+		klog.V(2).Infof("Adding node label from cloud provider: %s=%s", v1.LabelZoneFailureDomain, instanceMeta.Zone)
-		if err != nil {
+		klog.V(2).Infof("Adding node label from cloud provider: %s=%s", v1.LabelZoneFailureDomainStable, instanceMeta.Zone)
-			return nil, fmt.Errorf("failed to get zone from cloud provider: %v", err)
+		nodeModifiers = append(nodeModifiers, func(n *v1.Node) {
-		}
+			if n.Labels == nil {
-		if zone.FailureDomain != "" {
+				n.Labels = map[string]string{}
-			klog.V(2).Infof("Adding node label from cloud provider: %s=%s", v1.LabelZoneFailureDomain, zone.FailureDomain)
+			}
-			klog.V(2).Infof("Adding node label from cloud provider: %s=%s", v1.LabelZoneFailureDomainStable, zone.FailureDomain)
+			n.Labels[v1.LabelZoneFailureDomain] = instanceMeta.Zone
-			nodeModifiers = append(nodeModifiers, func(n *v1.Node) {
+			n.Labels[v1.LabelZoneFailureDomainStable] = instanceMeta.Zone
-				if n.Labels == nil {
+		})
-					n.Labels = map[string]string{}
-				}
-				n.Labels[v1.LabelZoneFailureDomain] = zone.FailureDomain
-				n.Labels[v1.LabelZoneFailureDomainStable] = zone.FailureDomain
-			})
-		}
-		if zone.Region != "" {
-			klog.V(2).Infof("Adding node label from cloud provider: %s=%s", v1.LabelZoneRegion, zone.Region)
-			klog.V(2).Infof("Adding node label from cloud provider: %s=%s", v1.LabelZoneRegionStable, zone.Region)
-			nodeModifiers = append(nodeModifiers, func(n *v1.Node) {
-				if n.Labels == nil {
-					n.Labels = map[string]string{}
-				}
-				n.Labels[v1.LabelZoneRegion] = zone.Region
-				n.Labels[v1.LabelZoneRegionStable] = zone.Region
-			})
-		}
 	}
+	if instanceMeta.Region != "" {
+		klog.V(2).Infof("Adding node label from cloud provider: %s=%s", v1.LabelZoneRegion, instanceMeta.Region)
+		klog.V(2).Infof("Adding node label from cloud provider: %s=%s", v1.LabelZoneRegionStable, instanceMeta.Region)
+		nodeModifiers = append(nodeModifiers, func(n *v1.Node) {
+			if n.Labels == nil {
+				n.Labels = map[string]string{}
+			}
+			n.Labels[v1.LabelZoneRegion] = instanceMeta.Region
+			n.Labels[v1.LabelZoneRegionStable] = instanceMeta.Region
+		})
+	}
+
 	return nodeModifiers, nil
 }
 

staging/src/k8s.io/cloud-provider/fake/fake.go

@@ -325,6 +325,8 @@ func (f *Cloud) InstanceMetadata(ctx context.Context, node *v1.Node) (*cloudprov
 		ProviderID:    node.Spec.ProviderID,
 		InstanceType:  f.InstanceTypes[types.NodeName(node.Spec.ProviderID)],
 		NodeAddresses: f.Addresses,
+		Zone:          f.Zone.FailureDomain,
+		Region:        f.Zone.Region,
 	}, f.Err
 }