Golang Machine.VolumeAttachments方法代碼示例

// machineVolumeParams retrieves VolumeParams for the volumes that should be
// provisioned with, and attached to, the machine. The client should ignore
// parameters that it does not know how to handle.
func (p *ProvisionerAPI) machineVolumeParams(m *state.Machine) ([]params.VolumeParams, error) {
	volumeAttachments, err := m.VolumeAttachments()
	if err != nil {
		return nil, err
	}
	if len(volumeAttachments) == 0 {
		return nil, nil
	}
	envConfig, err := p.st.EnvironConfig()
	if err != nil {
		return nil, err
	}
	poolManager := poolmanager.New(state.NewStateSettings(p.st))
	allVolumeParams := make([]params.VolumeParams, 0, len(volumeAttachments))
	for _, volumeAttachment := range volumeAttachments {
		volumeTag := volumeAttachment.Volume()
		volume, err := p.st.Volume(volumeTag)
		if err != nil {
			return nil, errors.Annotatef(err, "getting volume %q", volumeTag.Id())
		}
		storageInstance, err := storagecommon.MaybeAssignedStorageInstance(
			volume.StorageInstance, p.st.StorageInstance,
		)
		if err != nil {
			return nil, errors.Annotatef(err, "getting volume %q storage instance", volumeTag.Id())
		}
		volumeParams, err := storagecommon.VolumeParams(volume, storageInstance, envConfig, poolManager)
		if err != nil {
			return nil, errors.Annotatef(err, "getting volume %q parameters", volumeTag.Id())
		}
		provider, err := registry.StorageProvider(storage.ProviderType(volumeParams.Provider))
		if err != nil {
			return nil, errors.Annotate(err, "getting storage provider")
		}
		if provider.Dynamic() {
			// Leave dynamic storage to the storage provisioner.
			continue
		}
		volumeAttachmentParams, ok := volumeAttachment.Params()
		if !ok {
			// Attachment is already provisioned; this is an insane
			// state, so we should not proceed with the volume.
			return nil, errors.Errorf(
				"volume %s already attached to machine %s",
				volumeTag.Id(), m.Id(),
			)
		}
		// Not provisioned yet, so ask the cloud provisioner do it.
		volumeParams.Attachment = &params.VolumeAttachmentParams{
			volumeTag.String(),
			m.Tag().String(),
			"", // we're creating the volume, so it has no volume ID.
			"", // we're creating the machine, so it has no instance ID.
			volumeParams.Provider,
			volumeAttachmentParams.ReadOnly,
		}
		allVolumeParams = append(allVolumeParams, volumeParams)
	}
	return allVolumeParams, nil
}