// APIWorker returns a Worker that connects to the API and starts any
// workers that need an API connection.
//
// If a state worker is necessary, APIWorker calls ensureStateWorker.
func (a *MachineAgent) APIWorker(ensureStateWorker func()) (worker.Worker, error) {
st, entity, err := openAPIState(a.Conf.Conf, a)
if err != nil {
// There was an error connecting to the API,
// https://launchpad.net/bugs/1199915 means that we may just
// not have an API password set. So force a state connection at
// this point.
// TODO(jam): Once we can reliably trust that we have API
// passwords set, and we no longer need state
// connections (and possibly agents will be blocked
// from connecting directly to state) we can remove
// this. Currently needed because 1.10 does not set
// the API password and 1.11 requires it
ensureStateWorker()
return nil, err
}
m := entity.(*machineagent.Machine)
needsStateWorker := false
for _, job := range m.Jobs() {
needsStateWorker = needsStateWorker || stateJobs[job]
}
if needsStateWorker {
ensureStateWorker()
}
runner := worker.NewRunner(allFatal, moreImportant)
// Only the machiner currently connects to the API.
// Add other workers here as they are ready.
runner.StartWorker("machiner", func() (worker.Worker, error) {
return machiner.NewMachiner(st.Machiner(), a.Tag()), nil
})
return newCloseWorker(runner, st), nil // Note: a worker.Runner is itself a worker.Worker.
}
func (*runnerSuite) TestOneWorkerStartWhenStopping(c *C) {
worker.RestartDelay = 3 * time.Second
runner := worker.NewRunner(allFatal, noImportance)
starter := newTestWorkerStarter()
starter.stopWait = make(chan struct{})
err := runner.StartWorker("id", testWorkerStart(starter))
c.Assert(err, IsNil)
starter.assertStarted(c, true)
err = runner.StopWorker("id")
c.Assert(err, IsNil)
err = runner.StartWorker("id", testWorkerStart(starter))
c.Assert(err, IsNil)
close(starter.stopWait)
starter.assertStarted(c, false)
// Check that the task is restarted immediately without
// the usual restart timeout delay.
t0 := time.Now()
starter.assertStarted(c, true)
restartDuration := time.Since(t0)
if restartDuration > 1*time.Second {
c.Fatalf("task did not restart immediately")
}
c.Assert(worker.Stop(runner), IsNil)
}
func (*runnerSuite) TestOneWorkerStartFatalError(c *C) {
runner := worker.NewRunner(allFatal, noImportance)
starter := newTestWorkerStarter()
starter.startErr = errors.New("cannot start test task")
err := runner.StartWorker("id", testWorkerStart(starter))
c.Assert(err, IsNil)
err = runner.Wait()
c.Assert(err, Equals, starter.startErr)
}
func (*runnerSuite) TestOneWorkerStart(c *C) {
runner := worker.NewRunner(noneFatal, noImportance)
starter := newTestWorkerStarter()
err := runner.StartWorker("id", testWorkerStart(starter))
c.Assert(err, IsNil)
starter.assertStarted(c, true)
c.Assert(worker.Stop(runner), IsNil)
starter.assertStarted(c, false)
}
// Init initializes the command for running.
func (a *MachineAgent) Init(args []string) error {
if !state.IsMachineId(a.MachineId) {
return fmt.Errorf("--machine-id option must be set, and expects a non-negative integer")
}
if err := a.Conf.checkArgs(args); err != nil {
return err
}
a.runner = worker.NewRunner(isFatal, moreImportant)
return nil
}
// APIWorker returns a Worker that connects to the API and starts any
// workers that need an API connection.
//
// If a state worker is necessary, APIWorker calls ensureStateWorker.
func (a *MachineAgent) APIWorker(ensureStateWorker func()) (worker.Worker, error) {
st, entity, err := openAPIState(a.Conf.Conf, a)
if err != nil {
// There was an error connecting to the API,
// https://launchpad.net/bugs/1199915 means that we may just
// not have an API password set. So force a state connection at
// this point.
// TODO(jam): Once we can reliably trust that we have API
// passwords set, and we no longer need state
// connections (and possibly agents will be blocked
// from connecting directly to state) we can remove
// this. Currently needed because 1.10 does not set
// the API password and 1.11 requires it
ensureStateWorker()
return nil, err
}
needsStateWorker := false
for _, job := range entity.Jobs() {
needsStateWorker = needsStateWorker || stateJobs[job]
}
if needsStateWorker {
ensureStateWorker()
}
runner := worker.NewRunner(allFatal, moreImportant)
// Only the machiner currently connects to the API.
// Add other workers here as they are ready.
runner.StartWorker("machiner", func() (worker.Worker, error) {
return machiner.NewMachiner(st.Machiner(), a.Tag()), nil
})
runner.StartWorker("upgrader", func() (worker.Worker, error) {
// TODO(rog) use id instead of *Machine (or introduce Clone method)
return upgrader.New(st.Upgrader(), a.Tag(), a.Conf.DataDir), nil
})
for _, job := range entity.Jobs() {
switch job {
case params.JobHostUnits:
deployerTask, err := newDeployer(st.Deployer(), a.Tag(), a.Conf.DataDir)
if err != nil {
return nil, err
}
runner.StartWorker("deployer", func() (worker.Worker, error) {
return deployerTask, nil
})
case params.JobManageEnviron:
// Not yet implemented with the API.
case params.JobManageState:
// Not yet implemented with the API.
default:
// TODO(dimitern): Once all workers moved over to using
// the API, report "unknown job type" here.
}
}
return newCloseWorker(runner, st), nil // Note: a worker.Runner is itself a worker.Worker.
}
func (*runnerSuite) TestOneWorkerDieFatalError(c *C) {
runner := worker.NewRunner(allFatal, noImportance)
starter := newTestWorkerStarter()
err := runner.StartWorker("id", testWorkerStart(starter))
c.Assert(err, IsNil)
starter.assertStarted(c, true)
dieErr := errors.New("error when running")
starter.die <- dieErr
err = runner.Wait()
c.Assert(err, Equals, dieErr)
starter.assertStarted(c, false)
}
func (*runnerSuite) TestOneWorkerStopFatalError(c *C) {
runner := worker.NewRunner(allFatal, noImportance)
starter := newTestWorkerStarter()
starter.stopErr = errors.New("stop error")
err := runner.StartWorker("id", testWorkerStart(starter))
c.Assert(err, IsNil)
starter.assertStarted(c, true)
err = runner.StopWorker("id")
c.Assert(err, IsNil)
err = runner.Wait()
c.Assert(err, Equals, starter.stopErr)
}
func (a *UnitAgent) APIWorkers() (worker.Worker, error) {
st, entity, err := openAPIState(a.Conf.Conf, a)
if err != nil {
return nil, err
}
dataDir := a.Conf.DataDir
runner := worker.NewRunner(allFatal, moreImportant)
runner.StartWorker("upgrader", func() (worker.Worker, error) {
return upgrader.New(st.Upgrader(), entity.Tag(), dataDir), nil
})
return newCloseWorker(runner, st), nil
}
// Init initializes the command for running.
func (a *UnitAgent) Init(args []string) error {
if a.UnitName == "" {
return requiredError("unit-name")
}
if !names.IsUnit(a.UnitName) {
return fmt.Errorf(`--unit-name option expects "<service>/<n>" argument`)
}
if err := a.Conf.checkArgs(args); err != nil {
return err
}
a.runner = worker.NewRunner(isFatal, moreImportant)
return nil
}
// StateWorkers returns a worker that runs the unit agent workers.
func (a *UnitAgent) StateWorkers() (worker.Worker, error) {
st, entity, err := openState(a.Conf.Conf, a)
if err != nil {
return nil, err
}
unit := entity.(*state.Unit)
dataDir := a.Conf.DataDir
runner := worker.NewRunner(allFatal, moreImportant)
runner.StartWorker("uniter", func() (worker.Worker, error) {
return uniter.NewUniter(st, unit.Name(), dataDir), nil
})
return newCloseWorker(runner, st), nil
}
func (*runnerSuite) TestOneWorkerRestartDelay(c *C) {
worker.RestartDelay = 100 * time.Millisecond
runner := worker.NewRunner(noneFatal, noImportance)
starter := newTestWorkerStarter()
err := runner.StartWorker("id", testWorkerStart(starter))
c.Assert(err, IsNil)
starter.assertStarted(c, true)
starter.die <- fmt.Errorf("non-fatal error")
starter.assertStarted(c, false)
t0 := time.Now()
starter.assertStarted(c, true)
restartDuration := time.Since(t0)
if restartDuration < worker.RestartDelay {
c.Fatalf("restart delay was not respected; got %v want %v", restartDuration, worker.RestartDelay)
}
}
func (*runnerSuite) TestErrorImportance(c *C) {
moreImportant := func(err0, err1 error) bool {
return err0.(errorLevel) > err1.(errorLevel)
}
id := func(i int) string { return fmt.Sprint(i) }
runner := worker.NewRunner(allFatal, moreImportant)
for i := 0; i < 10; i++ {
starter := newTestWorkerStarter()
starter.stopErr = errorLevel(i)
err := runner.StartWorker(id(i), testWorkerStart(starter))
c.Assert(err, IsNil)
}
err := runner.StopWorker(id(4))
c.Assert(err, IsNil)
err = runner.Wait()
c.Assert(err, Equals, errorLevel(9))
}
func (*runnerSuite) TestOneWorkerRestart(c *C) {
runner := worker.NewRunner(noneFatal, noImportance)
starter := newTestWorkerStarter()
err := runner.StartWorker("id", testWorkerStart(starter))
c.Assert(err, IsNil)
starter.assertStarted(c, true)
// Check it restarts a few times time.
for i := 0; i < 3; i++ {
starter.die <- fmt.Errorf("an error")
starter.assertStarted(c, false)
starter.assertStarted(c, true)
}
c.Assert(worker.Stop(runner), IsNil)
starter.assertStarted(c, false)
}
func (*runnerSuite) TestAllWorkersStoppedWhenOneDiesWithFatalError(c *C) {
runner := worker.NewRunner(allFatal, noImportance)
var starters []*testWorkerStarter
for i := 0; i < 10; i++ {
starter := newTestWorkerStarter()
err := runner.StartWorker(fmt.Sprint(i), testWorkerStart(starter))
c.Assert(err, IsNil)
starters = append(starters, starter)
}
for _, starter := range starters {
starter.assertStarted(c, true)
}
dieErr := errors.New("fatal error")
starters[4].die <- dieErr
err := runner.Wait()
c.Assert(err, Equals, dieErr)
for _, starter := range starters {
starter.assertStarted(c, false)
}
}
func (*runnerSuite) TestFatalErrorWhileSelfStartWorker(c *C) {
// Original deadlock problem that this tests for:
// A worker tries to call StartWorker in its start function
// at the same time another worker dies with a fatal error.
// It might not be able to send on startc.
runner := worker.NewRunner(allFatal, noImportance)
selfStarter := newTestWorkerStarter()
// make the startNotify channel synchronous so
// we can delay the start indefinitely.
selfStarter.startNotify = make(chan bool)
selfStarter.hook = func() {
runner.StartWorker("another", func() (worker.Worker, error) {
return nil, fmt.Errorf("no worker started")
})
}
err := runner.StartWorker("self starter", testWorkerStart(selfStarter))
c.Assert(err, IsNil)
fatalStarter := newTestWorkerStarter()
fatalStarter.startErr = fmt.Errorf("a fatal error")
err = runner.StartWorker("fatal worker", testWorkerStart(fatalStarter))
c.Assert(err, IsNil)
// Wait for the runner loop to react to the fatal
// error and go into final shutdown mode.
time.Sleep(10 * time.Millisecond)
// At this point, the loop is in shutdown mode, but the
// selfStarter's worker is still in its start function.
// When the start function continues (the first assertStarted
// allows that to happen) it will try to create a new
// worker. This failed in an earlier version of the code because the
// loop was not ready to receive start requests.
selfStarter.assertStarted(c, true)
selfStarter.assertStarted(c, false)
err = runner.Wait()
c.Assert(err, Equals, fatalStarter.startErr)
}
// Workers returns a worker that runs the unit agent workers.
func (a *UnitAgent) Workers() (worker.Worker, error) {
st, entity, err := openState(a.Conf.Conf, a)
if err != nil {
return nil, err
}
if err := EnsureAPIInfo(a.Conf.Conf, st, entity); err != nil {
// We suppress this error, because it is probably more interesting
// to see other failures, but we log it, in case it is a root cause
agentLogger.Warningf("error while calling EnsureAPIInfo: %v", err)
}
unit := entity.(*state.Unit)
dataDir := a.Conf.DataDir
runner := worker.NewRunner(allFatal, moreImportant)
runner.StartWorker("upgrader", func() (worker.Worker, error) {
return NewUpgrader(st, unit, dataDir), nil
})
runner.StartWorker("uniter", func() (worker.Worker, error) {
return uniter.NewUniter(st, unit.Name(), dataDir), nil
})
return newCloseWorker(runner, st), nil
}
func (*runnerSuite) TestFatalErrorWhileStarting(c *C) {
// Original deadlock problem that this tests for:
// A worker dies with fatal error while another worker
// is inside start(). runWorker can't send startInfo on startedc.
runner := worker.NewRunner(allFatal, noImportance)
slowStarter := newTestWorkerStarter()
// make the startNotify channel synchronous so
// we can delay the start indefinitely.
slowStarter.startNotify = make(chan bool)
err := runner.StartWorker("slow starter", testWorkerStart(slowStarter))
c.Assert(err, IsNil)
fatalStarter := newTestWorkerStarter()
fatalStarter.startErr = fmt.Errorf("a fatal error")
err = runner.StartWorker("fatal worker", testWorkerStart(fatalStarter))
c.Assert(err, IsNil)
// Wait for the runner loop to react to the fatal
// error and go into final shutdown mode.
time.Sleep(10 * time.Millisecond)
// At this point, the loop is in shutdown mode, but the
// slowStarter's worker is still in its start function.
// When the start function continues (the first assertStarted
// allows that to happen) and returns the new Worker,
// runWorker will try to send it on runner.startedc.
// This test makes sure that succeeds ok.
slowStarter.assertStarted(c, true)
slowStarter.assertStarted(c, false)
err = runner.Wait()
c.Assert(err, Equals, fatalStarter.startErr)
}
// StateJobs returns a worker running all the workers that require
// a *state.State connection.
func (a *MachineAgent) StateWorker() (worker.Worker, error) {
st, entity, err := openState(a.Conf.Conf, a)
if err != nil {
return nil, err
}
// If this fails, other bits will fail, so we just log the error, and
// let the other failures actually restart runners
if err := EnsureAPIInfo(a.Conf.Conf, st, entity); err != nil {
log.Warningf("failed to EnsureAPIInfo: %v", err)
}
reportOpenedState(st)
m := entity.(*state.Machine)
// TODO(rog) use more discriminating test for errors
// rather than taking everything down indiscriminately.
dataDir := a.Conf.DataDir
runner := worker.NewRunner(allFatal, moreImportant)
runner.StartWorker("upgrader", func() (worker.Worker, error) {
// TODO(rog) use id instead of *Machine (or introduce Clone method)
return NewUpgrader(st, m, dataDir), nil
})
// At this stage, since we don't embed lxc containers, just start an lxc
// provisioner task for non-lxc containers. Since we have only LXC
// containers and normal machines, this effectively means that we only
// have an LXC provisioner when we have a normally provisioned machine
// (through the environ-provisioner). With the upcoming advent of KVM
// containers, it is likely that we will want an LXC provisioner on a KVM
// machine, and once we get nested LXC containers, we can remove this
// check.
providerType := os.Getenv("JUJU_PROVIDER_TYPE")
if providerType != provider.Local && m.ContainerType() != instance.LXC {
workerName := fmt.Sprintf("%s-provisioner", provisioner.LXC)
runner.StartWorker(workerName, func() (worker.Worker, error) {
return provisioner.NewProvisioner(provisioner.LXC, st, a.MachineId, dataDir), nil
})
}
// Take advantage of special knowledge here in that we will only ever want
// the storage provider on one machine, and that is the "bootstrap" node.
if providerType == provider.Local && m.Id() == bootstrapMachineId {
runner.StartWorker("local-storage", func() (worker.Worker, error) {
return localstorage.NewWorker(), nil
})
}
for _, job := range m.Jobs() {
switch job {
case state.JobHostUnits:
runner.StartWorker("deployer", func() (worker.Worker, error) {
return newDeployer(st, m.Id(), dataDir), nil
})
case state.JobManageEnviron:
runner.StartWorker("environ-provisioner", func() (worker.Worker, error) {
return provisioner.NewProvisioner(provisioner.ENVIRON, st, a.MachineId, dataDir), nil
})
runner.StartWorker("firewaller", func() (worker.Worker, error) {
return firewaller.NewFirewaller(st), nil
})
case state.JobManageState:
runner.StartWorker("apiserver", func() (worker.Worker, error) {
// If the configuration does not have the required information,
// it is currently not a recoverable error, so we kill the whole
// agent, potentially enabling human intervention to fix
// the agent's configuration file. In the future, we may retrieve
// the state server certificate and key from the state, and
// this should then change.
if len(a.Conf.StateServerCert) == 0 || len(a.Conf.StateServerKey) == 0 {
return nil, &fatalError{"configuration does not have state server cert/key"}
}
return apiserver.NewServer(st, fmt.Sprintf(":%d", a.Conf.APIPort), a.Conf.StateServerCert, a.Conf.StateServerKey)
})
runner.StartWorker("cleaner", func() (worker.Worker, error) {
return cleaner.NewCleaner(st), nil
})
runner.StartWorker("resumer", func() (worker.Worker, error) {
// The action of resumer is so subtle that it is not tested,
// because we can't figure out how to do so without brutalising
// the transaction log.
return resumer.NewResumer(st), nil
})
default:
log.Warningf("ignoring unknown job %q", job)
}
}
return newCloseWorker(runner, st), nil
}
func (*runnerSuite) TestStopWorkerWhenDead(c *C) {
runner := worker.NewRunner(allFatal, noImportance)
c.Assert(worker.Stop(runner), IsNil)
c.Assert(runner.StopWorker("foo"), Equals, worker.ErrDead)
}
