Golang StartInstanceParams.CleanupCallback方法代碼示例

// newRawInstance is where the new physical instance is actually
// provisioned, relative to the provided args and spec. Info for that
// low-level instance is returned.
func (env *environ) newRawInstance(args environs.StartInstanceParams) (*lxdclient.Instance, error) {
	hostname, err := env.namespace.Hostname(args.InstanceConfig.MachineId)
	if err != nil {
		return nil, errors.Trace(err)
	}

	// Note: other providers have the ImageMetadata already read for them
	// and passed in as args.ImageMetadata. However, lxd provider doesn't
	// use datatype: image-ids, it uses datatype: image-download, and we
	// don't have a registered cloud/region.
	imageSources, err := env.getImageSources()
	if err != nil {
		return nil, errors.Trace(err)
	}

	series := args.InstanceConfig.Series
	// TODO(jam): We should get this information from EnsureImageExists, or
	// something given to us from 'raw', not assume it ourselves.
	image := "ubuntu-" + series
	// TODO: support args.Constraints.Arch, we'll want to map from

	// Keep track of StatusCallback output so we may clean up later.
	// This is implemented here, close to where the StatusCallback calls
	// are made, instead of at a higher level in the package, so as not to
	// assume that all providers will have the same need to be implemented
	// in the same way.
	longestMsg := 0
	statusCallback := func(currentStatus status.Status, msg string) {
		if args.StatusCallback != nil {
			args.StatusCallback(currentStatus, msg, nil)
		}
		if len(msg) > longestMsg {
			longestMsg = len(msg)
		}
	}
	cleanupCallback := func() {
		if args.CleanupCallback != nil {
			args.CleanupCallback(strings.Repeat(" ", longestMsg))
		}
	}
	defer cleanupCallback()

	imageCallback := func(copyProgress string) {
		statusCallback(status.Allocating, copyProgress)
	}
	if err := env.raw.EnsureImageExists(series, imageSources, imageCallback); err != nil {
		return nil, errors.Trace(err)
	}
	cleanupCallback() // Clean out any long line of completed download status

	cloudcfg, err := cloudinit.New(series)
	if err != nil {
		return nil, errors.Trace(err)
	}

	var certificateFingerprint string
	if args.InstanceConfig.Controller != nil {
		// For controller machines, generate a certificate pair and write
		// them to the instance's disk in a well-defined location, along
		// with the server's certificate.
		certPEM, keyPEM, err := lxdshared.GenerateMemCert(true)
		if err != nil {
			return nil, errors.Trace(err)
		}
		cert := lxdclient.NewCert(certPEM, keyPEM)
		cert.Name = hostname

		// We record the certificate's fingerprint in metadata, so we can
		// remove the certificate along with the instance.
		certificateFingerprint, err = cert.Fingerprint()
		if err != nil {
			return nil, errors.Trace(err)
		}

		if err := env.raw.AddCert(cert); err != nil {
			return nil, errors.Annotatef(err, "adding certificate %q", cert.Name)
		}
		serverState, err := env.raw.ServerStatus()
		if err != nil {
			return nil, errors.Annotate(err, "getting server status")
		}
		cloudcfg.AddRunTextFile(clientCertPath, string(certPEM), 0600)
		cloudcfg.AddRunTextFile(clientKeyPath, string(keyPEM), 0600)
		cloudcfg.AddRunTextFile(serverCertPath, serverState.Environment.Certificate, 0600)
	}

	cloudcfg.SetAttr("hostname", hostname)
	cloudcfg.SetAttr("manage_etc_hosts", true)

	metadata, err := getMetadata(cloudcfg, args)
	if err != nil {
		return nil, errors.Trace(err)
	}
	if certificateFingerprint != "" {
		metadata[metadataKeyCertificateFingerprint] = certificateFingerprint
	}

//.........這裏部分代碼省略.........