fix: implement HasInstance() for OCI providers

This implements HasInstance() for the OCI instance pool and node pool providers.

cluster-autoscaler/cloudprovider/oci/instancepools/oci_cloud_provider.go

@@ -5,6 +5,8 @@ Copyright 2021-2023 Oracle and/or its affiliates.
 package instancepools
 
 import (
+	"strings"
+
 	"github.com/pkg/errors"
 	apiv1 "k8s.io/api/core/v1"
 	"k8s.io/apimachinery/pkg/api/resource"
@@ -19,7 +21,6 @@ import (
 	"k8s.io/client-go/rest"
 	"k8s.io/client-go/tools/clientcmd"
 	"k8s.io/klog/v2"
-	"strings"
 )
 
 // OciCloudProvider implements the CloudProvider interface for OCI. It contains an
@@ -66,8 +67,25 @@ func (ocp *OciCloudProvider) NodeGroupForNode(n *apiv1.Node) (cloudprovider.Node
 }
 
 // HasInstance returns whether a given node has a corresponding instance in this cloud provider
-func (ocp *OciCloudProvider) HasInstance(n *apiv1.Node) (bool, error) {
-	return true, cloudprovider.ErrNotImplemented
+func (ocp *OciCloudProvider) HasInstance(node *apiv1.Node) (bool, error) {
+	instance, err := ocicommon.NodeToOciRef(node)
+	if err != nil {
+		return false, err
+	}
+	instancePool, err := ocp.poolManager.GetInstancePoolForInstance(instance)
+	if err != nil {
+		return false, err
+	}
+	instances, err := ocp.poolManager.GetInstancePoolNodes(*instancePool)
+	if err != nil {
+		return false, err
+	}
+	for _, i := range instances {
+		if i.Id == instance.InstanceID {
+			return true, nil
+		}
+	}
+	return false, nil
 }
 
 // Pricing returns pricing model for this cloud provider or error if not available.

cluster-autoscaler/cloudprovider/oci/nodepools/oci_cloud_provider.go

@@ -70,8 +70,25 @@ func (ocp *OciCloudProvider) GetNodeGpuConfig(node *apiv1.Node) *cloudprovider.G
 }
 
 // HasInstance returns whether a given node has a corresponding instance in this cloud provider
-func (ocp *OciCloudProvider) HasInstance(n *apiv1.Node) (bool, error) {
-	return true, cloudprovider.ErrNotImplemented
+func (ocp *OciCloudProvider) HasInstance(node *apiv1.Node) (bool, error) {
+	instance, err := ocicommon.NodeToOciRef(node)
+	if err != nil {
+		return true, err
+	}
+	np, err := ocp.manager.GetNodePoolForInstance(instance)
+	if err != nil {
+		return true, err
+	}
+	nodes, err := ocp.manager.GetNodePoolNodes(np)
+	if err != nil {
+		return true, err
+	}
+	for _, n := range nodes {
+		if n.Id == instance.InstanceID {
+			return true, nil
+		}
+	}
+	return false, nil
 }
 
 // Pricing returns pricing model for this cloud provider or error if not available.