[PWX-24574] Added GetInstance() API for oracle cloud provider (#120)

Signed-off-by: Vinayak Shinde <vinayakshnd@gmail.com>

Author: vinayakshnd

backoff/exponential.go

@@ -89,6 +89,23 @@ func (e *exponentialBackoff) InspectInstanceGroupForInstance(instanceID string)
 	return instanceGroupInfo, origErr
 }
 
+func (e *exponentialBackoff) GetInstance(displayName string) (interface{}, error) {
+	var (
+		instanceDetails interface{}
+		origErr         error
+	)
+	conditionFn := func() (bool, error) {
+		instanceDetails, origErr = e.cloudOps.GetInstance(displayName)
+		msg := fmt.Sprintf("Failed to get instance details for instance: %v.", displayName)
+		return e.handleError(origErr, msg)
+	}
+	expErr := wait.ExponentialBackoff(e.backoff, conditionFn)
+	if expErr == wait.ErrWaitTimeout {
+		return nil, cloudops.NewStorageError(cloudops.ErrExponentialTimeout, origErr.Error(), "")
+	}
+	return instanceDetails, origErr
+}
+
 func (e *exponentialBackoff) SetInstanceGroupSize(instanceGroupID string,
 	count int64,
 	timeout time.Duration) error {

cloudops.go

@@ -97,6 +97,8 @@ type Compute interface {
 	// InspectInstanceGroupForInstance inspects the instance group to which the
 	// cloud instance with given ID belongs
 	InspectInstanceGroupForInstance(instanceID string) (*InstanceGroupInfo, error)
+	// GetInstance returns cloud provider specific instance details
+	GetInstance(displayName string) (interface{}, error)
 	// SetInstanceGroupSize sets desired node count per availability zone
 	// for given instance group
 	SetInstanceGroupSize(instanceGroupID string,

oracle/oracle.go

@@ -280,6 +280,26 @@ func (o *oracleOps) InspectInstance(instanceID string) (*cloudops.InstanceInfo,
 	}, nil
 }
 
+func (o *oracleOps) GetInstance(displayName string) (interface{}, error) {
+	listInstanceReq := core.ListInstancesRequest{
+		DisplayName:   common.String(displayName),
+		CompartmentId: common.String(o.compartmentID),
+	}
+
+	listInstanceResp, err := o.compute.ListInstances(context.Background(), listInstanceReq)
+	if err != nil {
+		return nil, err
+	}
+	if len(listInstanceResp.Items) == 0 {
+		return nil, fmt.Errorf("no oracle instance found with display name: %s", displayName)
+	}
+	// Currently, torpedo uses this API to fetch details of the instance created 
+	// by OKE. OKE ensures that all the worker nodes created, have unique display
+	// names. In future, if we require to use this API to get details of vanilla
+	// compute instances, then we can modify below array indexing.
+	return listInstanceResp.Items[0], nil
+}
+
 func (o *oracleOps) InspectInstanceGroupForInstance(instanceID string) (*cloudops.InstanceGroupInfo, error) {
 	getNodePoolReq := containerengine.GetNodePoolRequest{
 		NodePoolId: &o.poolID,
@@ -777,6 +797,10 @@ func (o *oracleOps) DeleteInstance(instanceID string, zone string, timeout time.
 		}
 	}
 
+	if nodePoolID == nil {
+		return fmt.Errorf("node pool containing instance [%s] not found", instanceID)
+	}
+
 	nodeDeleteReq := containerengine.DeleteNodeRequest{
 		NodePoolId:      nodePoolID,
 		NodeId:          &instanceID,

unsupported/unsupported.go

@@ -35,6 +35,12 @@ func (u *unsupportedCompute) InspectInstanceGroupForInstance(instanceID string)
 	}
 }
 
+func (u *unsupportedCompute) GetInstance(displayName string) (interface{}, error) {
+	return nil, &cloudops.ErrNotSupported{
+		Operation: "GetInstance",
+	}
+}
+
 func (u *unsupportedCompute) SetInstanceGroupSize(instanceGroupID string,
 	count int64,
 	timeout time.Duration) error {