instance_volume_attachment.go

package awstasks

import (
	"fmt"

	"github.com/aws/aws-sdk-go/aws"
	"github.com/aws/aws-sdk-go/service/ec2"
	"github.com/golang/glog"
	"k8s.io/kops/upup/pkg/fi"
	"k8s.io/kops/upup/pkg/fi/cloudup/awsup"
)

type InstanceVolumeAttachment struct {
	Instance *Instance
	Volume   *EBSVolume
	Device   *string
}

func (e *InstanceVolumeAttachment) String() string {
	return fi.TaskAsString(e)
}

func (e *InstanceVolumeAttachment) Find(c *fi.Context) (*InstanceVolumeAttachment, error) {
	cloud := c.Cloud.(*awsup.AWSCloud)

	instanceID := e.Instance.ID
	volumeID := e.Volume.ID

	if instanceID == nil || volumeID == nil {
		return nil, nil
	}

	instance, err := cloud.DescribeInstance(*instanceID)
	if err != nil {
		return nil, err
	}

	for _, bdm := range instance.BlockDeviceMappings {
		if bdm.Ebs == nil {
			continue
		}
		if aws.StringValue(bdm.Ebs.VolumeId) != *volumeID {
			continue
		}

		actual := &InstanceVolumeAttachment{
			Device:   bdm.DeviceName,
			Instance: &Instance{ID: instance.InstanceId},
			Volume:   &EBSVolume{ID: bdm.Ebs.VolumeId},
		}

		glog.V(2).Infof("found matching InstanceVolumeAttachmen")
		return actual, nil
	}

	return nil, nil
}

func (e *InstanceVolumeAttachment) Run(c *fi.Context) error {
	return fi.DefaultDeltaRunMethod(e, c)
}

func (s *InstanceVolumeAttachment) CheckChanges(a, e, changes *InstanceVolumeAttachment) error {
	if a != nil {
		if changes.Device != nil {
			// TODO: Support this?
			return fi.CannotChangeField("Device")
		}
	}

	if a == nil {
		if e.Device == nil {
			return fi.RequiredField("Device")
		}
	}
	return nil
}

func (_ *InstanceVolumeAttachment) RenderAWS(t *awsup.AWSAPITarget, a, e, changes *InstanceVolumeAttachment) error {
	if a == nil {
		err := t.WaitForInstanceRunning(*e.Instance.ID)
		if err != nil {
			return err
		}

		request := &ec2.AttachVolumeInput{
			InstanceId: e.Instance.ID,
			VolumeId:   e.Volume.ID,
			Device:     e.Device,
		}

		_, err = t.Cloud.EC2.AttachVolume(request)
		if err != nil {
			return fmt.Errorf("error creating InstanceVolumeAttachment: %v", err)
		}
	}

	return nil // no tags
}