modify error message when request volume is in use with other node

pkg/cloud/cloud.go

@@ -115,6 +115,9 @@ var (
 	// ErrAlreadyExists is returned when a resource is already existent.
 	ErrAlreadyExists = errors.New("Resource already exists")
 
+	// ErrVolumeInUse is returned when a volume is already attached to an instance.
+	ErrVolumeInUse = errors.New("Request volume is already attached to an instance")
+
 	// ErrMultiSnapshots is returned when multiple snapshots are found
 	// with the same ID
 	ErrMultiSnapshots = errors.New("Multiple snapshots with the same name found")
@@ -133,6 +136,7 @@ type Disk struct {
 	AvailabilityZone string
 	SnapshotID       string
 	OutpostArn       string
+	Attachments      []string
 }
 
 // DiskOptions represents parameters to create an EBS volume
@@ -378,7 +382,7 @@ func (c *cloud) AttachDisk(ctx context.Context, volumeID, nodeID string) (string
 		if err != nil {
 			if awsErr, ok := err.(awserr.Error); ok {
 				if awsErr.Code() == "VolumeInUse" {
-					return "", ErrAlreadyExists
+					return "", ErrVolumeInUse
 				}
 			}
 			return "", fmt.Errorf("could not attach volume %q to node %q: %v", volumeID, nodeID, err)
@@ -396,7 +400,9 @@ func (c *cloud) AttachDisk(ctx context.Context, volumeID, nodeID string) (string
 	// TODO: Double check the attachment to be 100% sure we attached the correct volume at the correct mountpoint
 	// It could happen otherwise that we see the volume attached from a previous/separate AttachVolume call,
 	// which could theoretically be against a different device (or even instance).
-
+	// TODO: Check volume capability matches for ALREADY_EXISTS
+	// This could happen when request volume already attached to request node,
+	// but is incompatible with the specified volume_capability or readonly flag
 	return device.Path, nil
 }
 
@@ -521,6 +527,7 @@ func (c *cloud) GetDiskByID(ctx context.Context, volumeID string) (*Disk, error)
 	}
 
 	volume, err := c.getVolume(ctx, request)
+
 	if err != nil {
 		return nil, err
 	}
@@ -530,6 +537,7 @@ func (c *cloud) GetDiskByID(ctx context.Context, volumeID string) (*Disk, error)
 		CapacityGiB:      aws.Int64Value(volume.Size),
 		AvailabilityZone: aws.StringValue(volume.AvailabilityZone),
 		OutpostArn:       aws.StringValue(volume.OutpostArn),
+		Attachments:      getVolumeAttachmentsList(volume),
 	}, nil
 }
 
@@ -1044,3 +1052,14 @@ func volumeModificationDone(state string) bool {
 	}
 	return false
 }
+
+func getVolumeAttachmentsList(volume *ec2.Volume) []string {
+	var volumeAttachmentList []string
+	for _, attachment := range volume.Attachments {
+		if attachment.State != nil && aws.StringValue(attachment.State) == "attached" {
+			volumeAttachmentList = append(volumeAttachmentList, aws.StringValue(attachment.InstanceId))
+		}
+	}
+
+	return volumeAttachmentList
+}

pkg/cloud/cloud_test.go

@@ -525,21 +525,34 @@ func TestGetDiskByID(t *testing.T) {
 		volumeID         string
 		availabilityZone string
 		outpostArn       string
+		attachments      *ec2.VolumeAttachment
 		expErr           error
 	}{
 		{
 			name:             "success: normal",
 			volumeID:         "vol-test-1234",
 			availabilityZone: expZone,
+			attachments:      &ec2.VolumeAttachment{},
 			expErr:           nil,
 		},
 		{
 			name:             "success: outpost volume",
 			volumeID:         "vol-test-1234",
 			availabilityZone: expZone,
 			outpostArn:       "arn:aws:outposts:us-west-2:111111111111:outpost/op-0aaa000a0aaaa00a0",
+			attachments:      &ec2.VolumeAttachment{},
 			expErr:           nil,
 		},
+		{
+			name:             "success: attached instance list",
+			volumeID:         "vol-test-1234",
+			availabilityZone: expZone,
+			outpostArn:       "arn:aws:outposts:us-west-2:111111111111:outpost/op-0aaa000a0aaaa00a0",
+			attachments: &ec2.VolumeAttachment{
+				InstanceId: aws.String("test-instance"),
+				State:      aws.String("attached")},
+			expErr: nil,
+		},
 		{
 			name:     "fail: DescribeVolumes returned generic error",
 			volumeID: "vol-test-1234",
@@ -561,6 +574,7 @@ func TestGetDiskByID(t *testing.T) {
 							VolumeId:         aws.String(tc.volumeID),
 							AvailabilityZone: aws.String(tc.availabilityZone),
 							OutpostArn:       aws.String(tc.outpostArn),
+							Attachments:      []*ec2.VolumeAttachment{tc.attachments},
 						},
 					},
 				},
@@ -585,6 +599,9 @@ func TestGetDiskByID(t *testing.T) {
 				if disk.OutpostArn != tc.outpostArn {
 					t.Fatalf("GetDisk() failed: expected outpostArn %q, got %q", tc.outpostArn, disk.OutpostArn)
 				}
+				if len(disk.Attachments) > 0 && disk.Attachments[0] != aws.StringValue(tc.attachments.InstanceId) {
+					t.Fatalf("GetDisk() failed: expected attachment instance %q, got %q", aws.StringValue(tc.attachments.InstanceId), disk.Attachments[0])
+				}
 			}
 
 			mockCtrl.Finish()

pkg/driver/controller.go

@@ -286,19 +286,21 @@ func (d *controllerService) ControllerPublishVolume(ctx context.Context, req *cs
 	if !d.cloud.IsExistInstance(ctx, nodeID) {
 		return nil, status.Errorf(codes.NotFound, "Instance %q not found", nodeID)
 	}
-
-	if _, err := d.cloud.GetDiskByID(ctx, volumeID); err != nil {
+	disk, err := d.cloud.GetDiskByID(ctx, volumeID)
+	if err != nil {
 		if err == cloud.ErrNotFound {
 			return nil, status.Error(codes.NotFound, "Volume not found")
 		}
 		return nil, status.Errorf(codes.Internal, "Could not get volume with ID %q: %v", volumeID, err)
 	}
 
+	// If given volumeId already assigned to given node, will directly return current device path
 	devicePath, err := d.cloud.AttachDisk(ctx, volumeID, nodeID)
 	if err != nil {
-		if err == cloud.ErrAlreadyExists {
-			return nil, status.Error(codes.AlreadyExists, err.Error())
+		if err == cloud.ErrVolumeInUse {
+			return nil, status.Error(codes.FailedPrecondition, strings.Join(disk.Attachments, ","))
 		}
+		// TODO: Check volume capability matches for ALREADY_EXISTS
 		return nil, status.Errorf(codes.Internal, "Could not attach volume %q to node %q: %v", volumeID, nodeID, err)
 	}
 	klog.V(5).Infof("ControllerPublishVolume: volume %s attached to node %s through device %s", volumeID, nodeID, devicePath)

pkg/driver/controller_test.go

@@ -2669,8 +2669,12 @@ func TestControllerPublishVolume(t *testing.T) {
 			},
 		},
 		{
-			name: "fail attach disk with already exists error",
+			name: "fail attach disk with volume already in use error",
 			testFunc: func(t *testing.T) {
+				attachedInstancId := "test-instance-id-attached"
+				disk := &cloud.Disk{
+					Attachments: []string{attachedInstancId},
+				}
 				req := &csi.ControllerPublishVolumeRequest{
 					VolumeId:         "does-not-exist",
 					NodeId:           expInstanceID,
@@ -2684,8 +2688,8 @@ func TestControllerPublishVolume(t *testing.T) {
 
 				mockCloud := mocks.NewMockCloud(mockCtl)
 				mockCloud.EXPECT().IsExistInstance(gomock.Eq(ctx), gomock.Eq(req.NodeId)).Return(true)
-				mockCloud.EXPECT().GetDiskByID(gomock.Eq(ctx), gomock.Any()).Return(&cloud.Disk{}, nil)
-				mockCloud.EXPECT().AttachDisk(gomock.Eq(ctx), gomock.Any(), gomock.Eq(req.NodeId)).Return("", cloud.ErrAlreadyExists)
+				mockCloud.EXPECT().GetDiskByID(gomock.Eq(ctx), gomock.Any()).Return(disk, nil)
+				mockCloud.EXPECT().AttachDisk(gomock.Eq(ctx), gomock.Any(), gomock.Eq(req.NodeId)).Return("", cloud.ErrVolumeInUse)
 
 				awsDriver := controllerService{
 					cloud:         mockCloud,
@@ -2697,8 +2701,11 @@ func TestControllerPublishVolume(t *testing.T) {
 					if !ok {
 						t.Fatalf("Could not get error status code from error: %v", srvErr)
 					}
-					if srvErr.Code() != codes.AlreadyExists {
-						t.Fatalf("Expected error code %d, got %d message %s", codes.AlreadyExists, srvErr.Code(), srvErr.Message())
+					if srvErr.Code() != codes.FailedPrecondition {
+						t.Fatalf("Expected error code %d, got %d message %s", codes.FailedPrecondition, srvErr.Code(), srvErr.Message())
+					}
+					if srvErr.Message() != attachedInstancId {
+						t.Fatalf("Expected error message to contain previous attached instanceId %s, but get error message %s", attachedInstancId, srvErr.Message())
 					}
 				} else {
 					t.Fatalf("Expected error %v, got no error", codes.AlreadyExists)