pkg/autoupdate: move status into task

As state should be kept in a single `task`.  This will allow for
separating updates from rollbacks which will be needed to support
multiple containers/tasks in a single unit.

[NO NEW TESTS NEEDED] - should not change behavior.

Signed-off-by: Valentin Rothberg <vrothberg@redhat.com>
This commit is contained in:
Valentin Rothberg
2022-08-03 15:07:08 +02:00
parent af3ce70844
commit 0df51bb6bc

View File

@@ -69,12 +69,14 @@ const (
// task includes data and state for updating a container
type task struct {
authfile string // Container-specific authfile
auto *updater // Reverse pointer to the updater
container *libpod.Container // Container to update
policy Policy // Update policy
image *libimage.Image // Original image before the update
unit string // Name of the systemd unit
authfile string // Container-specific authfile
auto *updater // Reverse pointer to the updater
container *libpod.Container // Container to update
policy Policy // Update policy
image *libimage.Image // Original image before the update
rawImageName string // The container's raw image name
status string // Auto-update status
unit string // Name of the systemd unit
}
// LookupPolicy looks up the corresponding Policy for the specified
@@ -179,170 +181,155 @@ func AutoUpdate(ctx context.Context, runtime *libpod.Runtime, options entities.A
}
for _, task := range tasks {
report, err := task.update(ctx)
err := func() error {
updateAvailable, err := task.updateAvailable(ctx)
if err != nil {
task.status = statusFailed
return fmt.Errorf("checking image updates for container %s: %w", task.container.ID(), err)
}
if !updateAvailable {
task.status = statusNotUpdated
return nil
}
if options.DryRun {
task.status = statusPending
return nil
}
if err := task.update(ctx); err != nil {
task.status = statusFailed
return fmt.Errorf("updating image for container %s: %w", task.container.ID(), err)
}
updateError := auto.restartSystemdUnit(ctx, unit)
if updateError == nil {
task.status = statusUpdated
return nil
}
if !options.Rollback {
task.status = statusFailed
return fmt.Errorf("restarting unit %s for container %s: %w", task.unit, task.container.ID(), err)
}
if err := task.rollbackImage(); err != nil {
task.status = statusFailed
return fmt.Errorf("rolling back image for container %s: %w", task.container.ID(), err)
}
if err := auto.restartSystemdUnit(ctx, unit); err != nil {
task.status = statusFailed
return fmt.Errorf("restarting unit %s for container %s during rollback: %w", task.unit, task.container.ID(), err)
}
task.status = statusRolledBack
return nil
}()
if err != nil {
errors = append(errors, err)
}
if report != nil {
allReports = append(allReports, report)
}
allReports = append(allReports, task.report())
}
}
return allReports, errors
}
// update the task according to its auto-update policy.
func (t *task) update(ctx context.Context) (*entities.AutoUpdateReport, error) {
// report creates an auto-update report for the task.
func (t *task) report() *entities.AutoUpdateReport {
return &entities.AutoUpdateReport{
ContainerID: t.container.ID(),
ContainerName: t.container.Name(),
ImageName: t.container.RawImageName(),
Policy: string(t.policy),
SystemdUnit: t.unit,
Updated: t.status,
}
}
// updateAvailable returns whether an update for the task is available.
func (t *task) updateAvailable(ctx context.Context) (bool, error) {
switch t.policy {
case PolicyRegistryImage:
return t.updateRegistry(ctx)
return t.registryUpdateAvailable(ctx)
case PolicyLocalImage:
return t.updateLocally(ctx)
return t.localUpdateAvailable()
default:
return nil, fmt.Errorf("unexpected auto-update policy %s for container %s", t.policy, t.container.ID())
return false, fmt.Errorf("unexpected auto-update policy %s for container %s", t.policy, t.container.ID())
}
}
// updateRegistry updates the image/container according to the "registry" policy.
func (t *task) updateRegistry(ctx context.Context) (*entities.AutoUpdateReport, error) {
cid := t.container.ID()
rawImageName := t.container.RawImageName()
if rawImageName == "" {
return nil, fmt.Errorf("registry auto-updating container %q: raw-image name is empty", cid)
// update the task according to its auto-update policy.
func (t *task) update(ctx context.Context) error {
switch t.policy {
case PolicyRegistryImage:
return t.registryUpdate(ctx)
case PolicyLocalImage:
// Nothing to do as the image is already available in the local storage.
return nil
default:
return fmt.Errorf("unexpected auto-update policy %s for container %s", t.policy, t.container.ID())
}
if t.unit == "" {
return nil, fmt.Errorf("auto-updating container %q: no %s label found", t.container.ID(), systemdDefine.EnvVariable)
}
report := &entities.AutoUpdateReport{
ContainerID: cid,
ContainerName: t.container.Name(),
ImageName: rawImageName,
Policy: PolicyRegistryImage,
SystemdUnit: t.unit,
Updated: statusFailed,
}
if _, updated := t.auto.updatedRawImages[rawImageName]; updated {
logrus.Infof("Auto-updating container %q using registry image %q", cid, rawImageName)
if err := t.auto.restartSystemdUnit(ctx, t.container, t.unit); err != nil {
return report, err
}
report.Updated = statusUpdated
return report, nil
}
needsUpdate, err := newerRemoteImageAvailable(ctx, t.image, rawImageName, t.authfile)
if err != nil {
return report, fmt.Errorf("registry auto-updating container %q: image check for %q failed: %w", cid, rawImageName, err)
}
if !needsUpdate {
report.Updated = statusNotUpdated
return report, nil
}
if t.auto.options.DryRun {
report.Updated = statusPending
return report, nil
}
if _, err := pullImage(ctx, t.auto.runtime, rawImageName, t.authfile); err != nil {
return report, fmt.Errorf("registry auto-updating container %q: image update for %q failed: %w", cid, rawImageName, err)
}
t.auto.updatedRawImages[rawImageName] = true
logrus.Infof("Auto-updating container %q using registry image %q", cid, rawImageName)
updateErr := t.auto.restartSystemdUnit(ctx, t.container, t.unit)
if updateErr == nil {
report.Updated = statusUpdated
return report, nil
}
if !t.auto.options.Rollback {
return report, updateErr
}
// To fallback, simply retag the old image and restart the service.
if err := t.image.Tag(rawImageName); err != nil {
return report, fmt.Errorf("falling back to previous image: %w", err)
}
t.auto.updatedRawImages[rawImageName] = false
if err := t.auto.restartSystemdUnit(ctx, t.container, t.unit); err != nil {
return report, fmt.Errorf("restarting unit with old image during fallback: %w", err)
}
report.Updated = statusRolledBack
return report, nil
}
// updateRegistry updates the image/container according to the "local" policy.
func (t *task) updateLocally(ctx context.Context) (*entities.AutoUpdateReport, error) {
cid := t.container.ID()
rawImageName := t.container.RawImageName()
if rawImageName == "" {
return nil, fmt.Errorf("locally auto-updating container %q: raw-image name is empty", cid)
// registryUpdateAvailable returns whether a new image on the registry is available.
func (t *task) registryUpdateAvailable(ctx context.Context) (bool, error) {
// The newer image has already been pulled for another task, so we know
// there's a newer one available.
if _, exists := t.auto.updatedRawImages[t.rawImageName]; exists {
return true, nil
}
if t.unit == "" {
return nil, fmt.Errorf("auto-updating container %q: no %s label found", t.container.ID(), systemdDefine.EnvVariable)
}
report := &entities.AutoUpdateReport{
ContainerID: cid,
ContainerName: t.container.Name(),
ImageName: rawImageName,
Policy: PolicyLocalImage,
SystemdUnit: t.unit,
Updated: statusFailed,
}
needsUpdate, err := newerLocalImageAvailable(t.auto.runtime, t.image, rawImageName)
remoteRef, err := docker.ParseReference("//" + t.rawImageName)
if err != nil {
return report, fmt.Errorf("locally auto-updating container %q: image check for %q failed: %w", cid, rawImageName, err)
return false, err
}
options := &libimage.HasDifferentDigestOptions{AuthFilePath: t.authfile}
return t.image.HasDifferentDigest(ctx, remoteRef, options)
}
// registryUpdate pulls down the image from the registry.
func (t *task) registryUpdate(ctx context.Context) error {
// The newer image has already been pulled for another task.
if _, exists := t.auto.updatedRawImages[t.rawImageName]; exists {
return nil
}
if !needsUpdate {
report.Updated = statusNotUpdated
return report, nil
if err := pullImage(ctx, t.auto.runtime, t.rawImageName, t.authfile); err != nil {
return fmt.Errorf("registry auto-updating container %q: image update for %q failed: %w", t.container.ID(), t.rawImageName, err)
}
if t.auto.options.DryRun {
report.Updated = statusPending
return report, nil
}
t.auto.updatedRawImages[t.rawImageName] = true
return nil
}
logrus.Infof("Auto-updating container %q using local image %q", cid, rawImageName)
updateErr := t.auto.restartSystemdUnit(ctx, t.container, t.unit)
if updateErr == nil {
report.Updated = statusUpdated
return report, nil
}
if !t.auto.options.Rollback {
return report, updateErr
// localUpdateAvailable returns whether a new image in the local storage is available.
func (t *task) localUpdateAvailable() (bool, error) {
localImg, _, err := t.auto.runtime.LibimageRuntime().LookupImage(t.rawImageName, nil)
if err != nil {
return false, err
}
return localImg.Digest().String() != t.image.Digest().String(), nil
}
// rollbackImage rolls back the task's image to the previous version before the update.
func (t *task) rollbackImage() error {
// To fallback, simply retag the old image and restart the service.
if err := t.image.Tag(rawImageName); err != nil {
return report, fmt.Errorf("falling back to previous image: %w", err)
if err := t.image.Tag(t.rawImageName); err != nil {
return err
}
if err := t.auto.restartSystemdUnit(ctx, t.container, t.unit); err != nil {
return report, fmt.Errorf("restarting unit with old image during fallback: %w", err)
}
report.Updated = statusRolledBack
return report, nil
t.auto.updatedRawImages[t.rawImageName] = false
return nil
}
// restartSystemdUnit restarts the systemd unit the container is running in.
func (u *updater) restartSystemdUnit(ctx context.Context, ctr *libpod.Container, unit string) error {
func (u *updater) restartSystemdUnit(ctx context.Context, unit string) error {
restartChan := make(chan string)
if _, err := u.conn.RestartUnitContext(ctx, unit, "replace", restartChan); err != nil {
return fmt.Errorf("auto-updating container %q: restarting systemd unit %q failed: %w", ctr.ID(), unit, err)
return err
}
// Wait for the restart to finish and actually check if it was
@@ -351,11 +338,11 @@ func (u *updater) restartSystemdUnit(ctx context.Context, ctr *libpod.Container,
switch result {
case "done":
logrus.Infof("Successfully restarted systemd unit %q of container %q", unit, ctr.ID())
logrus.Infof("Successfully restarted systemd unit %q", unit)
return nil
default:
return fmt.Errorf("auto-updating container %q: restarting systemd unit %q failed: expected %q but received %q", ctr.ID(), unit, "done", result)
return fmt.Errorf("expected %q but received %q", "done", result)
}
}
@@ -421,13 +408,21 @@ func (u *updater) assembleTasks(ctx context.Context) []error {
continue
}
rawImageName := ctr.RawImageName()
if rawImageName == "" {
errors = append(errors, fmt.Errorf("locally auto-updating container %q: raw-image name is empty", ctr.ID()))
continue
}
t := task{
authfile: labels[AuthfileLabel],
auto: u,
container: ctr,
policy: policy,
image: image,
unit: unit,
authfile: labels[AuthfileLabel],
auto: u,
container: ctr,
policy: policy,
image: image,
unit: unit,
rawImageName: rawImageName,
status: statusFailed, // must be updated later on
}
// Add the task to the unit.
@@ -454,35 +449,12 @@ func (u *updater) assembleImageMap(ctx context.Context) (map[string]*libimage.Im
return imageMap, nil
}
// newerRemoteImageAvailable returns true if there corresponding image on the remote
// registry is newer.
func newerRemoteImageAvailable(ctx context.Context, img *libimage.Image, origName string, authfile string) (bool, error) {
remoteRef, err := docker.ParseReference("//" + origName)
if err != nil {
return false, err
}
options := &libimage.HasDifferentDigestOptions{AuthFilePath: authfile}
return img.HasDifferentDigest(ctx, remoteRef, options)
}
// newerLocalImageAvailable returns true if the container and local image have different digests
func newerLocalImageAvailable(runtime *libpod.Runtime, img *libimage.Image, rawImageName string) (bool, error) {
localImg, _, err := runtime.LibimageRuntime().LookupImage(rawImageName, nil)
if err != nil {
return false, err
}
return localImg.Digest().String() != img.Digest().String(), nil
}
// pullImage pulls the specified image.
func pullImage(ctx context.Context, runtime *libpod.Runtime, name, authfile string) (*libimage.Image, error) {
func pullImage(ctx context.Context, runtime *libpod.Runtime, name, authfile string) error {
pullOptions := &libimage.PullOptions{}
pullOptions.AuthFilePath = authfile
pullOptions.Writer = os.Stderr
pulledImages, err := runtime.LibimageRuntime().Pull(ctx, name, config.PullPolicyAlways, pullOptions)
if err != nil {
return nil, err
}
return pulledImages[0], nil
_, err := runtime.LibimageRuntime().Pull(ctx, name, config.PullPolicyAlways, pullOptions)
return err
}