// watchStorageAttachment starts watching the storage attachment with
// the specified storage tag, waits for its first event, and records
// the information in the current snapshot.
func (w *RemoteStateWatcher) watchStorageAttachment(
tag names.StorageTag,
life params.Life,
in apiwatcher.NotifyWatcher,
) error {
var storageSnapshot StorageSnapshot
select {
case <-w.tomb.Dying():
return tomb.ErrDying
case _, ok := <-in.Changes():
if !ok {
return watcher.EnsureErr(in)
}
var err error
storageSnapshot, err = getStorageSnapshot(w.st, tag, w.unit.Tag())
if params.IsCodeNotProvisioned(err) {
// If the storage is unprovisioned, we still want to
// record the attachment, but we'll mark it as
// unattached. This allows the uniter to wait for
// pending storage attachments to be provisioned.
storageSnapshot = StorageSnapshot{Life: life}
} else if err != nil {
return errors.Annotatef(err, "processing initial storage attachment change")
}
}
w.current.Storage[tag] = storageSnapshot
w.storageAttachmentWatchers[tag] = newStorageAttachmentWatcher(
w.st, in, w.unit.Tag(), tag, w.storageAttachmentChanges,
)
return nil
}
// watchForProxyChanges kicks off a go routine to listen to the watcher and
// update the proxy settings.
func (u *Uniter) watchForProxyChanges(environWatcher apiwatcher.NotifyWatcher) {
go func() {
for {
select {
case <-u.tomb.Dying():
return
case _, ok := <-environWatcher.Changes():
logger.Debugf("new environment change")
if !ok {
return
}
environConfig, err := u.st.EnvironConfig()
if err != nil {
logger.Errorf("cannot load environment configuration: %v", err)
} else {
u.updatePackageProxy(environConfig)
}
}
}
}()
}
// WaitForEnviron waits for an valid environment to arrive from
// the given watcher. It terminates with tomb.ErrDying if
// it receives a value on dying.
func WaitForEnviron(w apiwatcher.NotifyWatcher, st EnvironConfigGetter, dying <-chan struct{}) (environs.Environ, error) {
for {
select {
case <-dying:
return nil, tomb.ErrDying
case _, ok := <-w.Changes():
if !ok {
return nil, watcher.EnsureErr(w)
}
config, err := st.EnvironConfig()
if err != nil {
return nil, err
}
environ, err := environs.New(config)
if err == nil {
return environ, nil
}
logger.Errorf("loaded invalid environment configuration: %v", err)
loadedInvalid()
}
}
}
func (w *storageprovisioner) loop() error {
var environConfigChanges <-chan struct{}
var volumesWatcher apiwatcher.StringsWatcher
var filesystemsWatcher apiwatcher.StringsWatcher
var volumesChanges <-chan []string
var filesystemsChanges <-chan []string
var volumeAttachmentsWatcher apiwatcher.MachineStorageIdsWatcher
var filesystemAttachmentsWatcher apiwatcher.MachineStorageIdsWatcher
var volumeAttachmentsChanges <-chan []params.MachineStorageId
var filesystemAttachmentsChanges <-chan []params.MachineStorageId
var machineBlockDevicesWatcher apiwatcher.NotifyWatcher
var machineBlockDevicesChanges <-chan struct{}
machineChanges := make(chan names.MachineTag)
environConfigWatcher, err := w.environ.WatchForEnvironConfigChanges()
if err != nil {
return errors.Annotate(err, "watching environ config")
}
defer watcher.Stop(environConfigWatcher, &w.tomb)
environConfigChanges = environConfigWatcher.Changes()
// Machine-scoped provisioners need to watch block devices, to create
// volume-backed filesystems.
if machineTag, ok := w.scope.(names.MachineTag); ok {
machineBlockDevicesWatcher, err = w.volumes.WatchBlockDevices(machineTag)
if err != nil {
return errors.Annotate(err, "watching block devices")
}
defer watcher.Stop(machineBlockDevicesWatcher, &w.tomb)
machineBlockDevicesChanges = machineBlockDevicesWatcher.Changes()
}
// The other watchers are started dynamically; stop only if started.
defer w.maybeStopWatcher(volumesWatcher)
defer w.maybeStopWatcher(volumeAttachmentsWatcher)
defer w.maybeStopWatcher(filesystemsWatcher)
defer w.maybeStopWatcher(filesystemAttachmentsWatcher)
startWatchers := func() error {
var err error
volumesWatcher, err = w.volumes.WatchVolumes()
if err != nil {
return errors.Annotate(err, "watching volumes")
}
filesystemsWatcher, err = w.filesystems.WatchFilesystems()
if err != nil {
return errors.Annotate(err, "watching filesystems")
}
volumeAttachmentsWatcher, err = w.volumes.WatchVolumeAttachments()
if err != nil {
return errors.Annotate(err, "watching volume attachments")
}
filesystemAttachmentsWatcher, err = w.filesystems.WatchFilesystemAttachments()
if err != nil {
return errors.Annotate(err, "watching filesystem attachments")
}
volumesChanges = volumesWatcher.Changes()
filesystemsChanges = filesystemsWatcher.Changes()
volumeAttachmentsChanges = volumeAttachmentsWatcher.Changes()
filesystemAttachmentsChanges = filesystemAttachmentsWatcher.Changes()
return nil
}
ctx := context{
scope: w.scope,
storageDir: w.storageDir,
volumeAccessor: w.volumes,
filesystemAccessor: w.filesystems,
life: w.life,
machineAccessor: w.machines,
statusSetter: w.status,
time: w.clock,
volumes: make(map[names.VolumeTag]storage.Volume),
volumeAttachments: make(map[params.MachineStorageId]storage.VolumeAttachment),
volumeBlockDevices: make(map[names.VolumeTag]storage.BlockDevice),
filesystems: make(map[names.FilesystemTag]storage.Filesystem),
filesystemAttachments: make(map[params.MachineStorageId]storage.FilesystemAttachment),
machines: make(map[names.MachineTag]*machineWatcher),
machineChanges: machineChanges,
schedule: schedule.NewSchedule(w.clock),
pendingVolumeBlockDevices: make(set.Tags),
incompleteVolumeParams: make(map[names.VolumeTag]storage.VolumeParams),
incompleteVolumeAttachmentParams: make(map[params.MachineStorageId]storage.VolumeAttachmentParams),
pendingFilesystems: make(map[names.FilesystemTag]storage.FilesystemParams),
pendingFilesystemAttachments: make(map[params.MachineStorageId]storage.FilesystemAttachmentParams),
pendingDyingFilesystemAttachments: make(map[params.MachineStorageId]storage.FilesystemAttachmentParams),
}
ctx.managedFilesystemSource = newManagedFilesystemSource(
ctx.volumeBlockDevices, ctx.filesystems,
)
defer func() {
for _, w := range ctx.machines {
w.stop()
}
}()
for {
// Check if any pending operations can be fulfilled.
if err := processPending(&ctx); err != nil {
return errors.Trace(err)
}
select {
case <-w.tomb.Dying():
return tomb.ErrDying
case _, ok := <-environConfigChanges:
if !ok {
return watcher.EnsureErr(environConfigWatcher)
}
environConfig, err := w.environ.EnvironConfig()
if err != nil {
return errors.Annotate(err, "getting environ config")
}
if ctx.environConfig == nil {
// We've received the initial environ config,
// so we can begin provisioning storage.
if err := startWatchers(); err != nil {
return err
}
}
ctx.environConfig = environConfig
case changes, ok := <-volumesChanges:
if !ok {
return watcher.EnsureErr(volumesWatcher)
}
if err := volumesChanged(&ctx, changes); err != nil {
return errors.Trace(err)
}
case changes, ok := <-volumeAttachmentsChanges:
if !ok {
return watcher.EnsureErr(volumeAttachmentsWatcher)
}
if err := volumeAttachmentsChanged(&ctx, changes); err != nil {
return errors.Trace(err)
}
case changes, ok := <-filesystemsChanges:
if !ok {
return watcher.EnsureErr(filesystemsWatcher)
}
if err := filesystemsChanged(&ctx, changes); err != nil {
return errors.Trace(err)
}
case changes, ok := <-filesystemAttachmentsChanges:
if !ok {
return watcher.EnsureErr(filesystemAttachmentsWatcher)
}
if err := filesystemAttachmentsChanged(&ctx, changes); err != nil {
return errors.Trace(err)
}
case _, ok := <-machineBlockDevicesChanges:
if !ok {
return watcher.EnsureErr(machineBlockDevicesWatcher)
}
if err := machineBlockDevicesChanged(&ctx); err != nil {
return errors.Trace(err)
}
case machineTag := <-machineChanges:
if err := refreshMachine(&ctx, machineTag); err != nil {
return errors.Trace(err)
}
case <-ctx.schedule.Next():
// Ready to pick something(s) off the pending queue.
if err := processSchedule(&ctx); err != nil {
return errors.Trace(err)
}
}
}
}
func (f *filter) loop(unitTag string) (err error) {
// TODO(dfc) named return value is a time bomb
defer func() {
if params.IsCodeNotFoundOrCodeUnauthorized(err) {
err = worker.ErrTerminateAgent
}
}()
tag, err := names.ParseUnitTag(unitTag)
if err != nil {
return err
}
if f.unit, err = f.st.Unit(tag); err != nil {
return err
}
if err = f.unitChanged(); err != nil {
return err
}
f.service, err = f.unit.Service()
if err != nil {
return err
}
if err = f.serviceChanged(); err != nil {
return err
}
unitw, err := f.unit.Watch()
if err != nil {
return err
}
defer f.maybeStopWatcher(unitw)
servicew, err := f.service.Watch()
if err != nil {
return err
}
defer f.maybeStopWatcher(servicew)
// configw and relationsw can get restarted, so we need to use
// their eventual values in the defer calls.
var configw apiwatcher.NotifyWatcher
var configChanges <-chan struct{}
curl, err := f.unit.CharmURL()
if err == nil {
configw, err = f.unit.WatchConfigSettings()
if err != nil {
return err
}
configChanges = configw.Changes()
f.upgradeFrom.url = curl
} else if err != uniter.ErrNoCharmURLSet {
filterLogger.Errorf("unit charm: %v", err)
return err
}
defer func() {
if configw != nil {
watcher.Stop(configw, &f.tomb)
}
}()
actionsw, err := f.unit.WatchActions()
if err != nil {
return err
}
f.actionsPending = make([]string, 0)
defer func() {
if actionsw != nil {
watcher.Stop(actionsw, &f.tomb)
}
}()
relationsw, err := f.service.WatchRelations()
if err != nil {
return err
}
defer func() {
if relationsw != nil {
watcher.Stop(relationsw, &f.tomb)
}
}()
var addressChanges <-chan struct{}
addressesw, err := f.unit.WatchAddresses()
if err != nil {
return err
}
defer watcher.Stop(addressesw, &f.tomb)
// Config events cannot be meaningfully discarded until one is available;
// once we receive the initial change, we unblock discard requests by
// setting this channel to its namesake on f.
var discardConfig chan struct{}
for {
var ok bool
select {
case <-f.tomb.Dying():
return tomb.ErrDying
// Handle watcher changes.
case _, ok = <-unitw.Changes():
filterLogger.Debugf("got unit change")
if !ok {
return watcher.MustErr(unitw)
}
if err = f.unitChanged(); err != nil {
return err
}
case _, ok = <-servicew.Changes():
filterLogger.Debugf("got service change")
if !ok {
return watcher.MustErr(servicew)
}
if err = f.serviceChanged(); err != nil {
return err
}
case _, ok = <-configChanges:
filterLogger.Debugf("got config change")
if !ok {
return watcher.MustErr(configw)
}
if addressChanges == nil {
// We start reacting to address changes after the
// first config-changed is processed, ignoring the
// initial address changed event.
addressChanges = addressesw.Changes()
if _, ok := <-addressChanges; !ok {
return watcher.MustErr(addressesw)
}
}
filterLogger.Debugf("preparing new config event")
f.outConfig = f.outConfigOn
discardConfig = f.discardConfig
case _, ok = <-addressChanges:
filterLogger.Debugf("got address change")
if !ok {
return watcher.MustErr(addressesw)
}
// address change causes config-changed event
filterLogger.Debugf("preparing new config event")
f.outConfig = f.outConfigOn
case ids, ok := <-actionsw.Changes():
filterLogger.Debugf("got %d actions", len(ids))
if !ok {
return watcher.MustErr(actionsw)
}
f.actionsPending = append(f.actionsPending, ids...)
f.nextAction = f.getNextAction()
case keys, ok := <-relationsw.Changes():
filterLogger.Debugf("got relations change")
if !ok {
return watcher.MustErr(relationsw)
}
var ids []int
for _, key := range keys {
relationTag := names.NewRelationTag(key).String()
rel, err := f.st.Relation(relationTag)
if params.IsCodeNotFoundOrCodeUnauthorized(err) {
// If it's actually gone, this unit cannot have entered
// scope, and therefore never needs to know about it.
} else if err != nil {
return err
} else {
ids = append(ids, rel.Id())
}
}
f.relationsChanged(ids)
// Send events on active out chans.
case f.outUpgrade <- f.upgrade:
filterLogger.Debugf("sent upgrade event")
f.outUpgrade = nil
case f.outResolved <- f.resolved:
filterLogger.Debugf("sent resolved event")
f.outResolved = nil
case f.outConfig <- nothing:
filterLogger.Debugf("sent config event")
f.outConfig = nil
case f.outAction <- f.nextAction:
f.nextAction = f.getNextAction()
filterLogger.Debugf("sent action event")
case f.outRelations <- f.relations:
filterLogger.Debugf("sent relations event")
f.outRelations = nil
f.relations = nil
// Handle explicit requests.
case curl := <-f.setCharm:
filterLogger.Debugf("changing charm to %q", curl)
// We need to restart the config watcher after setting the
// charm, because service config settings are distinct for
// different service charms.
if configw != nil {
if err := configw.Stop(); err != nil {
return err
}
}
if err := f.unit.SetCharmURL(curl); err != nil {
filterLogger.Debugf("failed setting charm url %q: %v", curl, err)
return err
}
select {
case <-f.tomb.Dying():
return tomb.ErrDying
case f.didSetCharm <- nothing:
}
configw, err = f.unit.WatchConfigSettings()
if err != nil {
return err
}
configChanges = configw.Changes()
// Restart the relations watcher.
if err := relationsw.Stop(); err != nil {
return err
}
relationsw, err = f.service.WatchRelations()
if err != nil {
return err
}
f.upgradeFrom.url = curl
if err = f.upgradeChanged(); err != nil {
return err
}
case force := <-f.wantForcedUpgrade:
filterLogger.Debugf("want forced upgrade %v", force)
f.upgradeFrom.force = force
if err = f.upgradeChanged(); err != nil {
return err
}
case <-f.wantResolved:
filterLogger.Debugf("want resolved event")
if f.resolved != params.ResolvedNone {
f.outResolved = f.outResolvedOn
}
case <-f.clearResolved:
filterLogger.Debugf("resolved event handled")
f.outResolved = nil
if err := f.unit.ClearResolved(); err != nil {
return err
}
if err := f.unitChanged(); err != nil {
return err
}
select {
case <-f.tomb.Dying():
return tomb.ErrDying
case f.didClearResolved <- nothing:
}
case <-discardConfig:
filterLogger.Debugf("discarded config event")
f.outConfig = nil
}
}
}
func stopWatcher(c *gc.C, w apiwatcher.NotifyWatcher) {
err := w.Stop()
c.Check(err, jc.ErrorIsNil)
}
func (f *filter) loop(unitTag names.UnitTag) (err error) {
// TODO(dfc) named return value is a time bomb
defer func() {
if params.IsCodeNotFoundOrCodeUnauthorized(err) {
err = worker.ErrTerminateAgent
}
}()
if f.unit, err = f.st.Unit(unitTag); err != nil {
return err
}
if err = f.unitChanged(); err != nil {
return err
}
if err = f.meterStatusChanged(); err != nil {
return err
}
f.service, err = f.unit.Service()
if err != nil {
return err
}
if err = f.serviceChanged(); err != nil {
return err
}
unitw, err := f.unit.Watch()
if err != nil {
return err
}
defer f.maybeStopWatcher(unitw)
servicew, err := f.service.Watch()
if err != nil {
return err
}
defer f.maybeStopWatcher(servicew)
// configw and relationsw can get restarted, so we need to use
// their eventual values in the defer calls.
var configw apiwatcher.NotifyWatcher
var configChanges <-chan struct{}
curl, err := f.unit.CharmURL()
if err == nil {
configw, err = f.unit.WatchConfigSettings()
if err != nil {
return err
}
configChanges = configw.Changes()
f.upgradeFrom.url = curl
} else if err != uniter.ErrNoCharmURLSet {
filterLogger.Errorf("unit charm: %v", err)
return err
}
defer f.maybeStopWatcher(configw)
actionsw, err := f.unit.WatchActionNotifications()
if err != nil {
return err
}
f.actionsPending = make([]string, 0)
defer f.maybeStopWatcher(actionsw)
relationsw, err := f.service.WatchRelations()
if err != nil {
return err
}
defer f.maybeStopWatcher(relationsw)
meterStatusw, err := f.unit.WatchMeterStatus()
if err != nil {
return err
}
defer f.maybeStopWatcher(meterStatusw)
addressesw, err := f.unit.WatchAddresses()
if err != nil {
return err
}
defer watcher.Stop(addressesw, &f.tomb)
storagew, err := f.unit.WatchStorage()
if err != nil {
return err
}
defer watcher.Stop(storagew, &f.tomb)
leaderSettingsw, err := f.st.LeadershipSettings.WatchLeadershipSettings(f.service.Tag().Id())
if err != nil {
return err
}
defer watcher.Stop(leaderSettingsw, &f.tomb)
// Ignore external requests for leader settings behaviour until we see the first change.
var discardLeaderSettings <-chan struct{}
var wantLeaderSettings <-chan bool
// By default we send all leaderSettings onwards.
sendLeaderSettings := true
// Config events cannot be meaningfully discarded until one is available;
// once we receive the initial config and address changes, we unblock
// discard requests by setting this channel to its namesake on f.
var discardConfig chan struct{}
var seenConfigChange bool
var seenAddressChange bool
maybePrepareConfigEvent := func() {
if !seenAddressChange {
filterLogger.Debugf("no address change seen yet, skipping config event")
return
}
if !seenConfigChange {
filterLogger.Debugf("no config change seen yet, skipping config event")
return
}
filterLogger.Debugf("preparing new config event")
f.outConfig = f.outConfigOn
discardConfig = f.discardConfig
}
for {
var ok bool
select {
case <-f.tomb.Dying():
return tomb.ErrDying
// Handle watcher changes.
case _, ok = <-unitw.Changes():
filterLogger.Debugf("got unit change")
if !ok {
return watcher.EnsureErr(unitw)
}
if err = f.unitChanged(); err != nil {
return err
}
case _, ok = <-servicew.Changes():
filterLogger.Debugf("got service change")
if !ok {
return watcher.EnsureErr(servicew)
}
if err = f.serviceChanged(); err != nil {
return err
}
case _, ok = <-configChanges:
filterLogger.Debugf("got config change")
if !ok {
return watcher.EnsureErr(configw)
}
seenConfigChange = true
maybePrepareConfigEvent()
case _, ok = <-addressesw.Changes():
filterLogger.Debugf("got address change")
if !ok {
return watcher.EnsureErr(addressesw)
}
seenAddressChange = true
maybePrepareConfigEvent()
case _, ok = <-meterStatusw.Changes():
filterLogger.Debugf("got meter status change")
if !ok {
return watcher.EnsureErr(meterStatusw)
}
if err = f.meterStatusChanged(); err != nil {
return errors.Trace(err)
}
case ids, ok := <-actionsw.Changes():
filterLogger.Debugf("got %d actions", len(ids))
if !ok {
return watcher.EnsureErr(actionsw)
}
f.actionsPending = append(f.actionsPending, ids...)
f.nextAction = f.getNextAction()
case keys, ok := <-relationsw.Changes():
filterLogger.Debugf("got relations change")
if !ok {
return watcher.EnsureErr(relationsw)
}
var ids []int
for _, key := range keys {
relationTag := names.NewRelationTag(key)
rel, err := f.st.Relation(relationTag)
if params.IsCodeNotFoundOrCodeUnauthorized(err) {
// If it's actually gone, this unit cannot have entered
// scope, and therefore never needs to know about it.
} else if err != nil {
return err
} else {
ids = append(ids, rel.Id())
}
}
f.relationsChanged(ids)
case ids, ok := <-storagew.Changes():
filterLogger.Debugf("got storage change")
if !ok {
return watcher.EnsureErr(storagew)
}
tags := make([]names.StorageTag, len(ids))
for i, id := range ids {
tag := names.NewStorageTag(id)
tags[i] = tag
}
f.storageChanged(tags)
case _, ok = <-leaderSettingsw.Changes():
filterLogger.Debugf("got leader settings change: ok=%t", ok)
if !ok {
return watcher.EnsureErr(leaderSettingsw)
}
if sendLeaderSettings {
// only send the leader settings changed event
// if it hasn't been explicitly disabled
f.outLeaderSettings = f.outLeaderSettingsOn
} else {
filterLogger.Debugf("not sending leader settings change (want=false)")
}
discardLeaderSettings = f.discardLeaderSettings
wantLeaderSettings = f.wantLeaderSettings
// Send events on active out chans.
case f.outUpgrade <- f.upgrade:
filterLogger.Debugf("sent upgrade event")
f.outUpgrade = nil
case f.outResolved <- f.resolved:
filterLogger.Debugf("sent resolved event")
f.outResolved = nil
case f.outConfig <- nothing:
filterLogger.Debugf("sent config event")
f.outConfig = nil
case f.outLeaderSettings <- nothing:
filterLogger.Debugf("sent leader settings event")
f.outLeaderSettings = nil
case f.outAction <- f.nextAction:
f.nextAction = f.getNextAction()
filterLogger.Debugf("sent action event")
case f.outRelations <- f.relations:
filterLogger.Debugf("sent relations event")
f.outRelations = nil
f.relations = nil
case f.outMeterStatus <- nothing:
filterLogger.Debugf("sent meter status change event")
f.outMeterStatus = nil
case f.outStorage <- f.storage:
filterLogger.Debugf("sent storage event")
f.outStorage = nil
f.storage = nil
// Handle explicit requests.
case curl := <-f.setCharm:
filterLogger.Debugf("changing charm to %q", curl)
// We need to restart the config watcher after setting the
// charm, because service config settings are distinct for
// different service charms.
if configw != nil {
if err := configw.Stop(); err != nil {
return err
}
}
if err := f.unit.SetCharmURL(curl); err != nil {
filterLogger.Debugf("failed setting charm url %q: %v", curl, err)
return err
}
select {
case <-f.tomb.Dying():
return tomb.ErrDying
case f.didSetCharm <- nothing:
}
configw, err = f.unit.WatchConfigSettings()
if err != nil {
return err
}
configChanges = configw.Changes()
// Restart the relations watcher.
if err := relationsw.Stop(); err != nil {
return err
}
relationsw, err = f.service.WatchRelations()
if err != nil {
return err
}
f.upgradeFrom.url = curl
if err = f.upgradeChanged(); err != nil {
return err
}
case force := <-f.wantForcedUpgrade:
filterLogger.Debugf("want forced upgrade %v", force)
f.upgradeFrom.force = force
if err = f.upgradeChanged(); err != nil {
return err
}
case <-f.wantResolved:
filterLogger.Debugf("want resolved event")
if f.resolved != params.ResolvedNone {
f.outResolved = f.outResolvedOn
}
case sendEvents := <-wantLeaderSettings:
filterLogger.Debugf("want leader settings event: %t", sendEvents)
sendLeaderSettings = sendEvents
if sendEvents {
// go ahead and send an event right now,
// they're waiting for us
f.outLeaderSettings = f.outLeaderSettingsOn
} else {
// Make sure we don't have a pending event
f.outLeaderSettings = nil
}
case <-f.clearResolved:
filterLogger.Debugf("resolved event handled")
f.outResolved = nil
if err := f.unit.ClearResolved(); err != nil {
return err
}
if err := f.unitChanged(); err != nil {
return err
}
select {
case <-f.tomb.Dying():
return tomb.ErrDying
case f.didClearResolved <- nothing:
}
case <-discardConfig:
filterLogger.Debugf("discarded config event")
f.outConfig = nil
case <-discardLeaderSettings:
filterLogger.Debugf("discarded leader settings event")
f.outLeaderSettings = nil
}
}
}