func (*functionSuite) TestMaskf(c *gc.C) {
first := errors.New("first")
err := errors.Maskf(first, "masked %d", 42) //err maskfTest
c.Assert(err.Error(), gc.Equals, "masked 42: first")
c.Assert(errors.Cause(err), gc.Equals, err)
c.Assert(errors.Details(err), jc.Contains, tagToLocation["maskfTest"].String())
c.Assert(errors.Maskf(nil, "mask"), gc.IsNil)
}
// Write atomically writes to disk the relation state change in hi.
// It must be called after the respective hook was executed successfully.
// Write doesn't validate hi but guarantees that successive writes of
// the same hi are idempotent.
func (d *StateDir) Write(hi hook.Info) (err error) {
defer errors.Maskf(&err, "failed to write %q hook info for %q on state directory", hi.Kind, hi.RemoteUnit)
if hi.Kind == hooks.RelationBroken {
return d.Remove()
}
name := strings.Replace(hi.RemoteUnit, "/", "-", 1)
path := filepath.Join(d.path, name)
if hi.Kind == hooks.RelationDeparted {
if err = os.Remove(path); err != nil && !os.IsNotExist(err) {
return err
}
// If atomic delete succeeded, update own state.
delete(d.state.Members, hi.RemoteUnit)
return nil
}
di := diskInfo{&hi.ChangeVersion, hi.Kind == hooks.RelationJoined}
if err := utils.WriteYaml(path, &di); err != nil {
return err
}
// If write was successful, update own state.
d.state.Members[hi.RemoteUnit] = hi.ChangeVersion
if hi.Kind == hooks.RelationJoined {
d.state.ChangedPending = hi.RemoteUnit
} else {
d.state.ChangedPending = ""
}
return nil
}
// Validate returns an error if the supplied hook.Info does not represent
// a valid change to the relation state. Hooks must always be validated
// against the current state before they are run, to ensure that the system
// meets its guarantees about hook execution order.
func (s *State) Validate(hi hook.Info) (err error) {
defer errors.Maskf(&err, "inappropriate %q for %q", hi.Kind, hi.RemoteUnit)
if hi.RelationId != s.RelationId {
return fmt.Errorf("expected relation %d, got relation %d", s.RelationId, hi.RelationId)
}
if s.Members == nil {
return fmt.Errorf(`relation is broken and cannot be changed further`)
}
unit, kind := hi.RemoteUnit, hi.Kind
if kind == hooks.RelationBroken {
if len(s.Members) == 0 {
return nil
}
return fmt.Errorf(`cannot run "relation-broken" while units still present`)
}
if s.ChangedPending != "" {
if unit != s.ChangedPending || kind != hooks.RelationChanged {
return fmt.Errorf(`expected "relation-changed" for %q`, s.ChangedPending)
}
} else if _, joined := s.Members[unit]; joined && kind == hooks.RelationJoined {
return fmt.Errorf("unit already joined")
} else if !joined && kind != hooks.RelationJoined {
return fmt.Errorf("unit has not joined")
}
return nil
}
func (*functionSuite) TestCause(c *gc.C) {
c.Assert(errors.Cause(nil), gc.IsNil)
c.Assert(errors.Cause(someErr), gc.Equals, someErr)
fmtErr := fmt.Errorf("simple")
c.Assert(errors.Cause(fmtErr), gc.Equals, fmtErr)
err := errors.Wrap(someErr, fmtErr)
c.Assert(errors.Cause(err), gc.Equals, fmtErr)
err = errors.Annotate(err, "annotated")
c.Assert(errors.Cause(err), gc.Equals, fmtErr)
err = errors.Maskf(err, "maksed")
c.Assert(errors.Cause(err), gc.Equals, err)
// Look for a file that we know isn't there.
dir := c.MkDir()
_, err = os.Stat(filepath.Join(dir, "not-there"))
c.Assert(os.IsNotExist(err), jc.IsTrue)
err = errors.Annotatef(err, "wrap it")
// Now the error itself isn't a 'IsNotExist'.
c.Assert(os.IsNotExist(err), jc.IsFalse)
// However if we use the Check method, it is.
c.Assert(os.IsNotExist(errors.Cause(err)), jc.IsTrue)
}
// Destroy ensures that the service and all its relations will be removed at
// some point; if the service has no units, and no relation involving the
// service has any units in scope, they are all removed immediately.
func (s *Service) Destroy() (err error) {
defer errors.Maskf(&err, "cannot destroy service %q", s)
defer func() {
if err == nil {
// This is a white lie; the document might actually be removed.
s.doc.Life = Dying
}
}()
svc := &Service{st: s.st, doc: s.doc}
for i := 0; i < 5; i++ {
switch ops, err := svc.destroyOps(); err {
case errRefresh:
case errAlreadyDying:
return nil
case nil:
if err := svc.st.runTransaction(ops); err != txn.ErrAborted {
return err
}
default:
return err
}
if err := svc.Refresh(); errors.IsNotFound(err) {
return nil
} else if err != nil {
return err
}
}
return ErrExcessiveContention
}
// Destroy ensures that the service and all its relations will be removed at
// some point; if the service has no units, and no relation involving the
// service has any units in scope, they are all removed immediately.
func (s *Service) Destroy() (err error) {
defer errors.Maskf(&err, "cannot destroy service %q", s)
defer func() {
if err == nil {
// This is a white lie; the document might actually be removed.
s.doc.Life = Dying
}
}()
svc := &Service{st: s.st, doc: s.doc}
buildTxn := func(attempt int) ([]txn.Op, error) {
if attempt > 0 {
if err := svc.Refresh(); errors.IsNotFound(err) {
return nil, jujutxn.ErrNoOperations
} else if err != nil {
return nil, err
}
}
switch ops, err := svc.destroyOps(); err {
case errRefresh:
case errAlreadyDying:
return nil, jujutxn.ErrNoOperations
case nil:
return ops, nil
default:
return nil, err
}
return nil, jujutxn.ErrTransientFailure
}
return s.st.run(buildTxn)
}
// AssignUnit places the unit on a machine. Depending on the policy, and the
// state of the environment, this may lead to new instances being launched
// within the environment.
func (st *State) AssignUnit(u *Unit, policy AssignmentPolicy) (err error) {
if !u.IsPrincipal() {
return fmt.Errorf("subordinate unit %q cannot be assigned directly to a machine", u)
}
defer errors.Maskf(&err, "cannot assign unit %q to machine", u)
var m *Machine
switch policy {
case AssignLocal:
m, err = st.Machine("0")
if err != nil {
return err
}
return u.AssignToMachine(m)
case AssignClean:
if _, err = u.AssignToCleanMachine(); err != noCleanMachines {
return err
}
return u.AssignToNewMachineOrContainer()
case AssignCleanEmpty:
if _, err = u.AssignToCleanEmptyMachine(); err != noCleanMachines {
return err
}
return u.AssignToNewMachineOrContainer()
case AssignNew:
return u.AssignToNewMachine()
}
return fmt.Errorf("unknown unit assignment policy: %q", policy)
}
// OpenPort sets the policy of the port with protocol and number to be opened.
func (u *Unit) OpenPort(protocol string, number int) (err error) {
port := network.Port{Protocol: protocol, Number: number}
defer errors.Maskf(&err, "cannot open port %v for unit %q", port, u)
ops := []txn.Op{{
C: u.st.units.Name,
Id: u.doc.Name,
Assert: notDeadDoc,
Update: bson.D{{"$addToSet", bson.D{{"ports", port}}}},
}}
err = u.st.runTransaction(ops)
if err != nil {
return onAbort(err, errDead)
}
found := false
for _, p := range u.doc.Ports {
if p == port {
found = true
break
}
}
if !found {
u.doc.Ports = append(u.doc.Ports, port)
}
return nil
}
// SetResolved marks the unit as having had any previous state transition
// problems resolved, and informs the unit that it may attempt to
// reestablish normal workflow. The resolved mode parameter informs
// whether to attempt to reexecute previous failed hooks or to continue
// as if they had succeeded before.
func (u *Unit) SetResolved(mode ResolvedMode) (err error) {
defer errors.Maskf(&err, "cannot set resolved mode for unit %q", u)
switch mode {
case ResolvedRetryHooks, ResolvedNoHooks:
default:
return fmt.Errorf("invalid error resolution mode: %q", mode)
}
// TODO(fwereade): assert unit has error status.
resolvedNotSet := bson.D{{"resolved", ResolvedNone}}
ops := []txn.Op{{
C: u.st.units.Name,
Id: u.doc.Name,
Assert: append(notDeadDoc, resolvedNotSet...),
Update: bson.D{{"$set", bson.D{{"resolved", mode}}}},
}}
if err := u.st.runTransaction(ops); err == nil {
u.doc.Resolved = mode
return nil
} else if err != txn.ErrAborted {
return err
}
if ok, err := isNotDead(u.st.units, u.doc.Name); err != nil {
return err
} else if !ok {
return errDead
}
// For now, the only remaining assert is that resolved was unset.
return fmt.Errorf("already resolved")
}
// SetConstraints replaces the current service constraints.
func (s *Service) SetConstraints(cons constraints.Value) (err error) {
unsupported, err := s.st.validateConstraints(cons)
if len(unsupported) > 0 {
logger.Warningf(
"setting constraints on service %q: unsupported constraints: %v", s.Name(), strings.Join(unsupported, ","))
} else if err != nil {
return err
}
if s.doc.Subordinate {
return ErrSubordinateConstraints
}
defer errors.Maskf(&err, "cannot set constraints")
if s.doc.Life != Alive {
return errNotAlive
}
ops := []txn.Op{
{
C: s.st.services.Name,
Id: s.doc.Name,
Assert: isAliveDoc,
},
setConstraintsOp(s.st, s.globalKey(), cons),
}
return onAbort(s.st.runTransaction(ops), errNotAlive)
}
// UpdateCloudCredential adds or updates a cloud credential with the given tag.
func (st *State) UpdateCloudCredential(tag names.CloudCredentialTag, credential cloud.Credential) error {
credentials := map[names.CloudCredentialTag]cloud.Credential{tag: credential}
buildTxn := func(attempt int) ([]txn.Op, error) {
cloudName := tag.Cloud().Id()
cloud, err := st.Cloud(cloudName)
if err != nil {
return nil, errors.Trace(err)
}
ops, err := validateCloudCredentials(cloud, cloudName, credentials)
if err != nil {
return nil, errors.Annotate(err, "validating cloud credentials")
}
_, err = st.CloudCredential(tag)
if err != nil && !errors.IsNotFound(err) {
return nil, errors.Maskf(err, "fetching cloud credentials")
}
if err == nil {
ops = append(ops, updateCloudCredentialOp(tag, credential))
} else {
ops = append(ops, createCloudCredentialOp(tag, credential))
}
return ops, nil
}
if err := st.run(buildTxn); err != nil {
return errors.Annotate(err, "updating cloud credentials")
}
return nil
}
// validate returns an error if the state violates expectations.
func (st State) validate() (err error) {
defer errors.Maskf(&err, "invalid uniter state")
hasHook := st.Hook != nil
hasCharm := st.CharmURL != nil
switch st.Op {
case Install:
if hasHook {
return fmt.Errorf("unexpected hook info")
}
fallthrough
case Upgrade:
if !hasCharm {
return fmt.Errorf("missing charm URL")
}
case Continue, RunHook:
if !hasHook {
return fmt.Errorf("missing hook info")
} else if hasCharm {
return fmt.Errorf("unexpected charm URL")
}
default:
return fmt.Errorf("unknown operation %q", st.Op)
}
switch st.OpStep {
case Queued, Pending, Done:
default:
return fmt.Errorf("unknown operation step %q", st.OpStep)
}
if hasHook {
return st.Hook.Validate()
}
return nil
}
// Destroy ensures that the relation will be removed at some point; if no units
// are currently in scope, it will be removed immediately.
func (r *Relation) Destroy() (err error) {
defer errors.Maskf(&err, "cannot destroy relation %q", r)
if len(r.doc.Endpoints) == 1 && r.doc.Endpoints[0].Role == charm.RolePeer {
return fmt.Errorf("is a peer relation")
}
defer func() {
if err == nil {
// This is a white lie; the document might actually be removed.
r.doc.Life = Dying
}
}()
rel := &Relation{r.st, r.doc}
// In this context, aborted transactions indicate that the number of units
// in scope have changed between 0 and not-0. The chances of 5 successive
// attempts each hitting this change -- which is itself an unlikely one --
// are considered to be extremely small.
buildTxn := func(attempt int) ([]txn.Op, error) {
if attempt > 0 {
if err := rel.Refresh(); errors.IsNotFound(err) {
return []txn.Op{}, nil
} else if err != nil {
return nil, err
}
}
ops, _, err := rel.destroyOps("")
if err == errAlreadyDying {
return nil, jujutxn.ErrNoOperations
} else if err != nil {
return nil, err
}
return ops, nil
}
return rel.st.run(buildTxn)
}
// ReadAllStateDirs loads and returns every StateDir persisted directly inside
// the supplied dirPath. If dirPath does not exist, no error is returned.
func ReadAllStateDirs(dirPath string) (dirs map[int]*StateDir, err error) {
defer errors.Maskf(&err, "cannot load relations state from %q", dirPath)
if _, err := os.Stat(dirPath); os.IsNotExist(err) {
return nil, nil
} else if err != nil {
return nil, err
}
fis, err := ioutil.ReadDir(dirPath)
if err != nil {
return nil, err
}
dirs = map[int]*StateDir{}
for _, fi := range fis {
// Entries with integer names must be directories containing StateDir
// data; all other names will be ignored.
relationId, err := strconv.Atoi(fi.Name())
if err != nil {
// This doesn't look like a relation.
continue
}
dir, err := ReadStateDir(dirPath, relationId)
if err != nil {
return nil, err
}
dirs[relationId] = dir
}
return dirs, nil
}
// SetMinUnits changes the number of minimum units required by the service.
func (s *Service) SetMinUnits(minUnits int) (err error) {
defer errors.Maskf(&err, "cannot set minimum units for service %q", s)
defer func() {
if err == nil {
s.doc.MinUnits = minUnits
}
}()
if minUnits < 0 {
return errors.New("cannot set a negative minimum number of units")
}
service := &Service{st: s.st, doc: s.doc}
// Removing the document never fails. Racing clients trying to create the
// document generate one failure, but the second attempt should succeed.
// If one client tries to update the document, and a racing client removes
// it, the former should be able to re-create the document in the second
// attempt. If the referred-to service advanced its life cycle to a not
// alive state, an error is returned after the first failing attempt.
buildTxn := func(attempt int) ([]txn.Op, error) {
if attempt > 0 {
if err := service.Refresh(); err != nil {
return nil, err
}
}
if service.doc.Life != Alive {
return nil, errors.New("service is no longer alive")
}
if minUnits == service.doc.MinUnits {
return nil, statetxn.ErrNoOperations
}
return setMinUnitsOps(service, minUnits), nil
}
return s.st.run(buildTxn)
}
// vpcNotUsablef returns an error which satisfies isVPCNotUsableError().
func vpcNotUsablef(optionalCause error, format string, args ...interface{}) error {
outerErr := errors.Errorf(format, args...)
if optionalCause != nil {
outerErr = errors.Maskf(optionalCause, format, args...)
}
innerErr, _ := outerErr.(*errors.Err) // cannot fail.
return &vpcNotUsableError{*innerErr}
}
// FinishMachineConfig sets fields on a MachineConfig that can be determined by
// inspecting a plain config.Config and the machine constraints at the last
// moment before bootstrapping. It assumes that the supplied Config comes from
// an environment that has passed through all the validation checks in the
// Bootstrap func, and that has set an agent-version (via finding the tools to,
// use for bootstrap, or otherwise).
// TODO(fwereade) This function is not meant to be "good" in any serious way:
// it is better that this functionality be collected in one place here than
// that it be spread out across 3 or 4 providers, but this is its only
// redeeming feature.
func FinishMachineConfig(mcfg *cloudinit.MachineConfig, cfg *config.Config, cons constraints.Value) (err error) {
defer errors.Maskf(&err, "cannot complete machine configuration")
if err := PopulateMachineConfig(
mcfg,
cfg.Type(),
cfg.AuthorizedKeys(),
cfg.SSLHostnameVerification(),
cfg.ProxySettings(),
cfg.AptProxySettings(),
cfg.PreferIPv6(),
); err != nil {
return err
}
// The following settings are only appropriate at bootstrap time. At the
// moment, the only state server is the bootstrap node, but this
// will probably change.
if !mcfg.Bootstrap {
return nil
}
if mcfg.APIInfo != nil || mcfg.MongoInfo != nil {
return fmt.Errorf("machine configuration already has api/state info")
}
caCert, hasCACert := cfg.CACert()
if !hasCACert {
return fmt.Errorf("environment configuration has no ca-cert")
}
password := cfg.AdminSecret()
if password == "" {
return fmt.Errorf("environment configuration has no admin-secret")
}
passwordHash := utils.UserPasswordHash(password, utils.CompatSalt)
mcfg.APIInfo = &api.Info{Password: passwordHash, CACert: caCert}
mcfg.MongoInfo = &authentication.MongoInfo{Password: passwordHash, Info: mongo.Info{CACert: caCert}}
// These really are directly relevant to running a state server.
cert, key, err := cfg.GenerateStateServerCertAndKey()
if err != nil {
return errors.Annotate(err, "cannot generate state server certificate")
}
srvInfo := params.StateServingInfo{
StatePort: cfg.StatePort(),
APIPort: cfg.APIPort(),
Cert: string(cert),
PrivateKey: string(key),
SystemIdentity: mcfg.SystemPrivateSSHKey,
}
mcfg.StateServingInfo = &srvInfo
mcfg.Constraints = cons
if mcfg.Config, err = BootstrapConfig(cfg); err != nil {
return err
}
return nil
}
// Remove removes the network interface from state.
func (ni *NetworkInterface) Remove() (err error) {
defer errors.Maskf(&err, "cannot remove network interface %q", ni)
ops := []txn.Op{{
C: networkInterfacesC,
Id: ni.doc.Id,
Remove: true,
}}
// The only abort conditions in play indicate that the network interface
// has already been removed.
return onAbort(ni.st.runTransaction(ops), nil)
}
// SetProvisioned sets the provider specific machine id, nonce and also metadata for
// this machine. Once set, the instance id cannot be changed.
//
// When provisioning an instance, a nonce should be created and passed
// when starting it, before adding the machine to the state. This means
// that if the provisioner crashes (or its connection to the state is
// lost) after starting the instance, we can be sure that only a single
// instance will be able to act for that machine.
func (m *Machine) SetProvisioned(id instance.Id, nonce string, characteristics *instance.HardwareCharacteristics) (err error) {
defer errors.Maskf(&err, "cannot set instance data for machine %q", m)
if id == "" || nonce == "" {
return fmt.Errorf("instance id and nonce cannot be empty")
}
if characteristics == nil {
characteristics = &instance.HardwareCharacteristics{}
}
instData := &instanceData{
Id: m.doc.Id,
InstanceId: id,
Arch: characteristics.Arch,
Mem: characteristics.Mem,
RootDisk: characteristics.RootDisk,
CpuCores: characteristics.CpuCores,
CpuPower: characteristics.CpuPower,
Tags: characteristics.Tags,
}
// SCHEMACHANGE
// TODO(wallyworld) - do not check instanceId on machineDoc after schema is upgraded
notSetYet := bson.D{{"instanceid", ""}, {"nonce", ""}}
ops := []txn.Op{
{
C: m.st.machines.Name,
Id: m.doc.Id,
Assert: append(isAliveDoc, notSetYet...),
Update: bson.D{{"$set", bson.D{{"instanceid", id}, {"nonce", nonce}}}},
}, {
C: m.st.instanceData.Name,
Id: m.doc.Id,
Assert: txn.DocMissing,
Insert: instData,
},
}
if err = m.st.runTransaction(ops); err == nil {
m.doc.Nonce = nonce
// SCHEMACHANGE
// TODO(wallyworld) - remove this backward compatibility code when schema upgrades are possible
// (InstanceId is stored on the instanceData document but we duplicate the value on the machineDoc.
m.doc.InstanceId = id
return nil
} else if err != txn.ErrAborted {
return err
} else if alive, err := isAlive(m.st.machines, m.doc.Id); err != nil {
return err
} else if !alive {
return errNotAlive
}
return fmt.Errorf("already set")
}
func serviceRelations(st *State, name string) (relations []*Relation, err error) {
defer errors.Maskf(&err, "can't get relations for service %q", name)
docs := []relationDoc{}
err = st.relations.Find(bson.D{{"endpoints.servicename", name}}).All(&docs)
if err != nil {
return nil, err
}
for _, v := range docs {
relations = append(relations, newRelation(st, &v))
}
return relations, nil
}
// EnsureMinUnits adds new units if the service's MinUnits value is greater
// than the number of alive units.
func (s *Service) EnsureMinUnits() (err error) {
defer errors.Maskf(&err, "cannot ensure minimum units for service %q", s)
service := &Service{st: s.st, doc: s.doc}
for {
// Ensure the service is alive.
if service.doc.Life != Alive {
return errors.New("service is not alive")
}
// Exit without errors if the MinUnits for the service is not set.
if service.doc.MinUnits == 0 {
return nil
}
// Retrieve the number of alive units for the service.
aliveUnits, err := aliveUnitsCount(service)
if err != nil {
return err
}
// Calculate the number of required units to be added.
missing := service.doc.MinUnits - aliveUnits
if missing <= 0 {
return nil
}
name, ops, err := ensureMinUnitsOps(service)
if err != nil {
return err
}
// Add missing unit.
switch err := s.st.runTransaction(ops); err {
case nil:
// Assign the new unit.
unit, err := service.Unit(name)
if err != nil {
return err
}
if err := service.st.AssignUnit(unit, AssignNew); err != nil {
return err
}
// No need to proceed and refresh the service if this was the
// last/only missing unit.
if missing == 1 {
return nil
}
case txn.ErrAborted:
// Refresh the service and restart the loop.
default:
return err
}
if err := service.Refresh(); err != nil {
return err
}
}
}
// download fetches the supplied charm and checks that it has the correct sha256
// hash, then copies it into the directory. If a value is received on abort, the
// download will be stopped.
func (d *BundlesDir) download(info BundleInfo, abort <-chan struct{}) (err error) {
archiveURL, disableSSLHostnameVerification, err := info.ArchiveURL()
if err != nil {
return err
}
defer errors.Maskf(&err, "failed to download charm %q from %q", info.URL(), archiveURL)
dir := d.downloadsPath()
if err := os.MkdirAll(dir, 0755); err != nil {
return err
}
aurl := archiveURL.String()
logger.Infof("downloading %s from %s", info.URL(), aurl)
if disableSSLHostnameVerification {
logger.Infof("SSL hostname verification disabled")
}
dl := downloader.New(aurl, dir, disableSSLHostnameVerification)
defer dl.Stop()
for {
select {
case <-abort:
logger.Infof("download aborted")
return fmt.Errorf("aborted")
case st := <-dl.Done():
if st.Err != nil {
return st.Err
}
logger.Infof("download complete")
defer st.File.Close()
actualSha256, _, err := utils.ReadSHA256(st.File)
if err != nil {
return err
}
archiveSha256, err := info.ArchiveSha256()
if err != nil {
return err
}
if actualSha256 != archiveSha256 {
return fmt.Errorf(
"expected sha256 %q, got %q", archiveSha256, actualSha256,
)
}
logger.Infof("download verified")
if err := os.MkdirAll(d.path, 0755); err != nil {
return err
}
// Renaming an open file is not possible on Windows
st.File.Close()
return os.Rename(st.File.Name(), d.bundlePath(info))
}
}
}
// SetAnnotations adds key/value pairs to annotations in MongoDB.
func (a *annotator) SetAnnotations(pairs map[string]string) (err error) {
defer errors.Maskf(&err, "cannot update annotations on %s", a.tag)
if len(pairs) == 0 {
return nil
}
// Collect in separate maps pairs to be inserted/updated or removed.
toRemove := make(map[string]bool)
toInsert := make(map[string]string)
toUpdate := make(map[string]string)
for key, value := range pairs {
if strings.Contains(key, ".") {
return fmt.Errorf("invalid key %q", key)
}
if value == "" {
toRemove["annotations."+key] = true
} else {
toInsert[key] = value
toUpdate["annotations."+key] = value
}
}
// Two attempts should be enough to update annotations even with racing
// clients - if the document does not already exist, one of the clients
// will create it and the others will fail, then all the rest of the
// clients should succeed on their second attempt. If the referred-to
// entity has disappeared, and removed its annotations in the meantime,
// we consider that worthy of an error (will be fixed when new entities
// can never share names with old ones).
for i := 0; i < 2; i++ {
var ops []txn.Op
if count, err := a.st.annotations.FindId(a.globalKey).Count(); err != nil {
return err
} else if count == 0 {
// Check that the annotator entity was not previously destroyed.
if i != 0 {
return fmt.Errorf("%s no longer exists", a.tag)
}
ops, err = a.insertOps(toInsert)
if err != nil {
return err
}
} else {
ops = a.updateOps(toUpdate, toRemove)
}
if err := a.st.runTransaction(ops); err == nil {
return nil
} else if err != txn.ErrAborted {
return err
}
}
return ErrExcessiveContention
}
// Remove removes the unit from state, and may remove its service as well, if
// the service is Dying and no other references to it exist. It will fail if
// the unit is not Dead.
func (u *Unit) Remove() (err error) {
defer errors.Maskf(&err, "cannot remove unit %q", u)
if u.doc.Life != Dead {
return stderrors.New("unit is not dead")
}
// Now the unit is Dead, we can be sure that it's impossible for it to
// enter relation scopes (once it's Dying, we can be sure of this; but
// EnsureDead does not require that it already be Dying, so this is the
// only point at which we can safely backstop lp:1233457 and mitigate
// the impact of unit agent bugs that leave relation scopes occupied).
relations, err := serviceRelations(u.st, u.doc.Service)
if err != nil {
return err
}
for _, rel := range relations {
ru, err := rel.Unit(u)
if err != nil {
return err
}
if err := ru.LeaveScope(); err != nil {
return err
}
}
// Now we're sure we haven't left any scopes occupied by this unit, we
// can safely remove the document.
unit := &Unit{st: u.st, doc: u.doc}
buildTxn := func(attempt int) ([]txn.Op, error) {
if attempt > 0 {
if err := unit.Refresh(); errors.IsNotFound(err) {
return nil, statetxn.ErrNoOperations
} else if err != nil {
return nil, err
}
}
switch ops, err := unit.removeOps(isDeadDoc); err {
case errRefresh:
case errAlreadyDying:
return nil, statetxn.ErrNoOperations
case nil:
return ops, nil
default:
return nil, err
}
return nil, statetxn.ErrNoOperations
}
return unit.st.run(buildTxn)
}
// ReadSettings returns a map holding the settings of the unit with the
// supplied name within this relation. An error will be returned if the
// relation no longer exists, or if the unit's service is not part of the
// relation, or the settings are invalid; but mere non-existence of the
// unit is not grounds for an error, because the unit settings are
// guaranteed to persist for the lifetime of the relation, regardless
// of the lifetime of the unit.
func (ru *RelationUnit) ReadSettings(uname string) (m map[string]interface{}, err error) {
defer errors.Maskf(&err, "cannot read settings for unit %q in relation %q", uname, ru.relation)
if !names.IsValidUnit(uname) {
return nil, fmt.Errorf("%q is not a valid unit name", uname)
}
key, err := ru.key(uname)
if err != nil {
return nil, err
}
node, err := readSettings(ru.st, key)
if err != nil {
return nil, err
}
return node.Map(), nil
}
// Remove removes the unit from state, and may remove its service as well, if
// the service is Dying and no other references to it exist. It will fail if
// the unit is not Dead.
func (u *Unit) Remove() (err error) {
defer errors.Maskf(&err, "cannot remove unit %q", u)
if u.doc.Life != Dead {
return stderrors.New("unit is not dead")
}
// Now the unit is Dead, we can be sure that it's impossible for it to
// enter relation scopes (once it's Dying, we can be sure of this; but
// EnsureDead does not require that it already be Dying, so this is the
// only point at which we can safely backstop lp:1233457 and mitigate
// the impact of unit agent bugs that leave relation scopes occupied).
relations, err := serviceRelations(u.st, u.doc.Service)
if err != nil {
return err
}
for _, rel := range relations {
ru, err := rel.Unit(u)
if err != nil {
return err
}
if err := ru.LeaveScope(); err != nil {
return err
}
}
// Now we're sure we haven't left any scopes occupied by this unit, we
// can safely remove the document.
unit := &Unit{st: u.st, doc: u.doc}
for i := 0; i < 5; i++ {
switch ops, err := unit.removeOps(isDeadDoc); err {
case errRefresh:
case errAlreadyRemoved:
return nil
case nil:
if err := u.st.runTransaction(ops); err != txn.ErrAborted {
return err
}
default:
return err
}
if err := unit.Refresh(); errors.IsNotFound(err) {
return nil
} else if err != nil {
return err
}
}
return ErrExcessiveContention
}
func runDecode(fileName string) ([]byte, error) {
cmd := exec.Command("node", "./decode.js", fileName)
// Get package main path and set it as work directory.
if _, currentFile, _, ok := runtime.Caller(1); ok {
cmd.Dir = path.Join(path.Dir(currentFile), "..")
}
data, err := cmd.CombinedOutput()
if err != nil {
return nil, errors.Maskf(err, "stderr: %s", data)
}
err = os.Remove(fileName)
if err != nil {
return nil, errors.Trace(err)
}
return data, nil
}
// ReadStateDir loads a StateDir from the subdirectory of dirPath named
// for the supplied RelationId. If the directory does not exist, no error
// is returned,
func ReadStateDir(dirPath string, relationId int) (d *StateDir, err error) {
d = &StateDir{
filepath.Join(dirPath, strconv.Itoa(relationId)),
State{relationId, map[string]int64{}, ""},
}
defer errors.Maskf(&err, "cannot load relation state from %q", d.path)
if _, err := os.Stat(d.path); os.IsNotExist(err) {
return d, nil
} else if err != nil {
return nil, err
}
fis, err := ioutil.ReadDir(d.path)
if err != nil {
return nil, err
}
for _, fi := range fis {
// Entries with names ending in "-" followed by an integer must be
// files containing valid unit data; all other names are ignored.
name := fi.Name()
i := strings.LastIndex(name, "-")
if i == -1 {
continue
}
svcName := name[:i]
unitId := name[i+1:]
if _, err := strconv.Atoi(unitId); err != nil {
continue
}
unitName := svcName + "/" + unitId
var info diskInfo
if err = utils.ReadYaml(filepath.Join(d.path, name), &info); err != nil {
return nil, fmt.Errorf("invalid unit file %q: %v", name, err)
}
if info.ChangeVersion == nil {
return nil, fmt.Errorf(`invalid unit file %q: "changed-version" not set`, name)
}
d.state.Members[unitName] = *info.ChangeVersion
if info.ChangedPending {
if d.state.ChangedPending != "" {
return nil, fmt.Errorf("%q and %q both have pending changed hooks", d.state.ChangedPending, unitName)
}
d.state.ChangedPending = unitName
}
}
return d, nil
}
// newTempCertFile stores the given x509 certificate in a temporary file,
// which only the current user will be allowed to access.
// You *must* clean up the file after use, by calling its Delete method.
func newTempCertFile(data []byte) (certFile *tempCertFile, err error) {
// Add context to any error we may return.
defer errors.Maskf(&err, "failed while writing temporary certificate file")
// Access permissions for these temporary files:
const (
// Owner can read/write temporary files. Not backed up.
fileMode = 0600 | os.ModeTemporary | os.ModeExclusive
// Temporary dirs are like files, but owner also has "x"
// permission.
dirMode = fileMode | 0100
)
certFile = &tempCertFile{}
// We'll randomize the file's name, so that even someone with access
// to the temporary directory (perhaps a group member sneaking in
// just before we close access to the directory) won't be able to
// guess its name and inject their own file.
certFile.filename = fmt.Sprintf("x509-%d.cert", rand.Int31())
// To guarantee that nobody else will be able to access the file, even
// by predicting or guessing its name, we create the file in its own
// private directory.
certFile.tempDir, err = ioutil.TempDir("", "juju-azure")
if err != nil {
return nil, err
}
err = os.Chmod(certFile.tempDir, dirMode)
if err != nil {
return nil, err
}
// Now, at last, write the file. WriteFile could have done most of
// the work on its own, but it doesn't guarantee that nobody creates
// a file of the same name first. When that happens, you get a file
// but not with the requested permissions.
err = ioutil.WriteFile(certFile.Path(), data, fileMode)
if err != nil {
os.RemoveAll(certFile.tempDir)
return nil, err
}
return certFile, nil
}
// SetAgentVersion sets the version of juju that the agent is
// currently running.
func (m *Machine) SetAgentVersion(v version.Binary) (err error) {
defer errors.Maskf(&err, "cannot set agent version for machine %v", m)
if err = checkVersionValidity(v); err != nil {
return err
}
tools := &tools.Tools{Version: v}
ops := []txn.Op{{
C: m.st.machines.Name,
Id: m.doc.Id,
Assert: notDeadDoc,
Update: bson.D{{"$set", bson.D{{"tools", tools}}}},
}}
if err := m.st.runTransaction(ops); err != nil {
return onAbort(err, errDead)
}
m.doc.Tools = tools
return nil
}
