// MergeOutput waits for the given tasks to complete. meanwhile it logs each time a task
// process completes or generates an error. when shouldQuit closes, tasks are canceled and this
// func eventually returns once all ongoing event handlers have completed running.
func MergeOutput(tasks []*Task, shouldQuit <-chan struct{}) Events {
tc := make(chan *Completion)
var waitForTasks sync.WaitGroup
waitForTasks.Add(len(tasks))
for _, t := range tasks {
t := t
// translate task dead signal into Done
go func() {
<-t.done
waitForTasks.Done()
}()
// fan-in task completion and error events to tc, ec
go t.forwardUntil(tc, shouldQuit)
}
tclistener := make(chan *Completion)
done := runtime.After(func() {
completionFinished := runtime.After(func() {
defer close(tclistener)
forwardCompletionUntil(tc, tclistener, nil, shouldQuit, func(tt *Completion, shutdown bool) {
prefix := ""
if shutdown {
prefix = "(shutdown) "
}
log.Infof(prefix+"task %q exited with status %d", tt.name, tt.code)
})
})
waitForTasks.Wait()
close(tc)
<-completionFinished
})
ei := newEventsImpl(tclistener, done)
return ei
}
// spawns a go-routine to watch for unscheduled pods and queue them up
// for scheduling. returns immediately.
func (q *queuer) Run(done <-chan struct{}) {
go runtime.Until(func() {
log.Info("Watching for newly created pods")
q.lock.Lock()
defer q.lock.Unlock()
for {
// limit blocking here for short intervals so that scheduling
// may proceed even if there have been no recent pod changes
p := q.podUpdates.Await(enqueuePopTimeout)
if p == nil {
signalled := runtime.After(q.deltaCond.Wait)
// we've yielded the lock
select {
case <-time.After(enqueueWaitTimeout):
q.deltaCond.Broadcast() // abort Wait()
<-signalled // wait for lock re-acquisition
log.V(4).Infoln("timed out waiting for a pod update")
case <-signalled:
// we've acquired the lock and there may be
// changes for us to process now
}
continue
}
pod := p.(*Pod)
if recoverAssignedSlave(pod.Pod) != "" {
log.V(3).Infof("dequeuing assigned pod for scheduling: %v", pod.Pod.Name)
q.dequeue(pod.GetUID())
} else if pod.InGracefulTermination() {
// pods which are pre-scheduled (i.e. NodeName is set) may be gracefully deleted,
// even though they are not running yet.
log.V(3).Infof("dequeuing graceful deleted pre-scheduled pod for scheduling: %v", pod.Pod.Name)
q.dequeue(pod.GetUID())
} else {
// use ReplaceExisting because we are always pushing the latest state
now := time.Now()
pod.deadline = &now
if q.podQueue.Offer(pod, queue.ReplaceExisting) {
q.unscheduledCond.Broadcast()
log.V(3).Infof("queued pod for scheduling: %v", pod.Pod.Name)
} else {
log.Warningf("failed to queue pod for scheduling: %v", pod.Pod.Name)
}
}
}
}, 1*time.Second, done)
}
// OnError spawns a goroutine that waits for an error. if a non-nil error is read from
// the channel then the handler func is invoked, otherwise (nil error or closed chan)
// the handler is skipped. if a nil handler is specified then it's not invoked.
// the signal chan that's returned closes once the error process logic (and handler,
// if any) has completed.
func OnError(ch <-chan error, f func(error), abort <-chan struct{}) <-chan struct{} {
return runtime.After(func() {
if ch == nil {
return
}
select {
case err, ok := <-ch:
if ok && err != nil && f != nil {
f(err)
}
case <-abort:
if f != nil {
f(errProcessTerminated)
}
}
})
}
// Notify runs Elect() on m, and calls Start()/Stop() on s when the
// elected master starts/stops matching 'id'. Never returns.
func Notify(m MasterElector, path, id string, s Service, abort <-chan struct{}) {
n := ¬ifier{id: Master(id), service: s}
n.changed = make(chan struct{})
finished := runtime.After(func() {
runtime.Until(func() {
for {
w := m.Elect(path, id)
for {
select {
case <-abort:
return
case event, open := <-w.ResultChan():
if !open {
break
}
if event.Type != watch.Modified {
continue
}
electedMaster, ok := event.Object.(Master)
if !ok {
glog.Errorf("Unexpected object from election channel: %v", event.Object)
break
}
n.lock.Lock()
n.desired = electedMaster
n.lock.Unlock()
// notify serviceLoop, but don't block. If a change
// is queued already it will see the new n.desired.
select {
case n.changed <- struct{}{}:
}
}
}
}
}, 0, abort)
})
runtime.Until(func() { n.serviceLoop(finished) }, 0, abort)
}
func Test(t *testing.T) {
m := NewFake()
changes := make(chan bool, 1500)
done := make(chan struct{})
s := &slowService{t: t, changes: changes, done: done}
// change master to "notme" such that the initial m.Elect call inside Notify
// will trigger an obversable event. We will wait for it to make sure the
// Notify loop will see those master changes triggered by the go routine below.
m.ChangeMaster(Master("me"))
temporaryWatch := m.mux.Watch()
ch := temporaryWatch.ResultChan()
notifyDone := runtime.After(func() { Notify(m, "", "me", s, done) })
// wait for the event triggered by the initial m.Elect of Notify. Then drain
// the channel to not block anything.
<-ch
temporaryWatch.Stop()
for i := 0; i < len(ch); i += 1 { // go 1.3 and 1.4 compatible loop
<-ch
}
go func() {
defer close(done)
for i := 0; i < 500; i++ {
for _, key := range []string{"me", "notme", "alsonotme"} {
m.ChangeMaster(Master(key))
}
}
}()
<-notifyDone
close(changes)
changesNum := len(changes)
if changesNum > 1000 || changesNum == 0 {
t.Errorf("unexpected number of changes: %v", changesNum)
}
}
// implementation of scheduling plugin's NextPod func; see k8s plugin/pkg/scheduler
func (q *queuer) yield() *api.Pod {
log.V(2).Info("attempting to yield a pod")
q.lock.Lock()
defer q.lock.Unlock()
for {
// limit blocking here to short intervals so that we don't block the
// enqueuer Run() routine for very long
kpod := q.podQueue.Await(yieldPopTimeout)
if kpod == nil {
signalled := runtime.After(q.unscheduledCond.Wait)
// lock is yielded at this point and we're going to wait for either
// a timeout, or a signal that there's data
select {
case <-time.After(yieldWaitTimeout):
q.unscheduledCond.Broadcast() // abort Wait()
<-signalled // wait for the go-routine, and the lock
log.V(4).Infoln("timed out waiting for a pod to yield")
case <-signalled:
// we have acquired the lock, and there
// may be a pod for us to pop now
}
continue
}
pod := kpod.(*Pod).Pod
if podName, err := cache.MetaNamespaceKeyFunc(pod); err != nil {
log.Warningf("yield unable to understand pod object %+v, will skip: %v", pod, err)
} else if !q.podUpdates.Poll(podName, queue.POP_EVENT) {
log.V(1).Infof("yield popped a transitioning pod, skipping: %+v", pod)
} else if recoverAssignedSlave(pod) != "" {
// should never happen if enqueuePods is filtering properly
log.Warningf("yield popped an already-scheduled pod, skipping: %+v", pod)
} else {
return pod
}
}
}
// intended to be run with -race
func TestProc_doWithNestedXConcurrent(t *testing.T) {
config := defaultConfig
config.actionQueueDepth = 4000
p := newConfigured(config)
var wg sync.WaitGroup
const CONC = 20
wg.Add(CONC)
for i := 0; i < CONC; i++ {
i := i
errOnce := NewErrorOnce(p.Done())
runtime.After(func() { runDelegationTest(t, p, fmt.Sprintf("nested%d", i), errOnce) }).Then(wg.Done)
go func() {
err, _ := <-errOnce.Err()
if err != nil {
t.Fatalf("delegate %d: unexpected error: %v", i, err)
}
}()
}
wg.Wait()
<-p.End()
<-p.Done()
}
// TestExecutorLaunchAndKillTask ensures that the executor is able to launch
// and kill tasks while properly bookkeping its tasks.
func TestExecutorLaunchAndKillTask(t *testing.T) {
// create a fake pod watch. We use that below to submit new pods to the scheduler
podListWatch := NewMockPodsListWatch(api.PodList{})
// create fake apiserver
testApiServer := NewTestServer(t, api.NamespaceDefault, &podListWatch.list)
defer testApiServer.server.Close()
mockDriver := &MockExecutorDriver{}
updates := make(chan interface{}, 1024)
config := Config{
Docker: dockertools.ConnectToDockerOrDie("fake://"),
Updates: updates,
APIClient: client.NewOrDie(&client.Config{
Host: testApiServer.server.URL,
Version: testapi.Default.Version(),
}),
Kubelet: &fakeKubelet{
Kubelet: &kubelet.Kubelet{},
hostIP: net.IPv4(127, 0, 0, 1),
},
PodStatusFunc: func(kl KubeletInterface, pod *api.Pod) (*api.PodStatus, error) {
return &api.PodStatus{
ContainerStatuses: []api.ContainerStatus{
{
Name: "foo",
State: api.ContainerState{
Running: &api.ContainerStateRunning{},
},
},
},
Phase: api.PodRunning,
}, nil
},
}
executor := New(config)
executor.Init(mockDriver)
executor.Registered(mockDriver, nil, nil, nil)
select {
case <-updates:
case <-time.After(time.Second):
t.Fatalf("Executor should send an initial update on Registration")
}
pod := NewTestPod(1)
podTask, err := podtask.New(api.NewDefaultContext(), "",
*pod, &mesosproto.ExecutorInfo{})
assert.Equal(t, nil, err, "must be able to create a task from a pod")
taskInfo := podTask.BuildTaskInfo()
data, err := testapi.Default.Codec().Encode(pod)
assert.Equal(t, nil, err, "must be able to encode a pod's spec data")
taskInfo.Data = data
var statusUpdateCalls sync.WaitGroup
statusUpdateDone := func(_ mock.Arguments) { statusUpdateCalls.Done() }
statusUpdateCalls.Add(1)
mockDriver.On(
"SendStatusUpdate",
mesosproto.TaskState_TASK_STARTING,
).Return(mesosproto.Status_DRIVER_RUNNING, nil).Run(statusUpdateDone).Once()
statusUpdateCalls.Add(1)
mockDriver.On(
"SendStatusUpdate",
mesosproto.TaskState_TASK_RUNNING,
).Return(mesosproto.Status_DRIVER_RUNNING, nil).Run(statusUpdateDone).Once()
executor.LaunchTask(mockDriver, taskInfo)
assertext.EventuallyTrue(t, 5*time.Second, func() bool {
executor.lock.Lock()
defer executor.lock.Unlock()
return len(executor.tasks) == 1 && len(executor.pods) == 1
}, "executor must be able to create a task and a pod")
gotPodUpdate := false
select {
case m := <-updates:
update, ok := m.(kubelet.PodUpdate)
if ok && len(update.Pods) == 1 {
gotPodUpdate = true
}
case <-time.After(time.Second):
}
assert.Equal(t, true, gotPodUpdate,
"the executor should send an update about a new pod to "+
"the updates chan when creating a new one.")
// Allow some time for asynchronous requests to the driver.
finished := kmruntime.After(statusUpdateCalls.Wait)
select {
case <-finished:
case <-time.After(5 * time.Second):
t.Fatalf("timed out waiting for status update calls to finish")
}
statusUpdateCalls.Add(1)
mockDriver.On(
"SendStatusUpdate",
mesosproto.TaskState_TASK_KILLED,
).Return(mesosproto.Status_DRIVER_RUNNING, nil).Run(statusUpdateDone).Once()
executor.KillTask(mockDriver, taskInfo.TaskId)
assertext.EventuallyTrue(t, 5*time.Second, func() bool {
executor.lock.Lock()
defer executor.lock.Unlock()
return len(executor.tasks) == 0 && len(executor.pods) == 0
}, "executor must be able to kill a created task and pod")
// Allow some time for asynchronous requests to the driver.
finished = kmruntime.After(statusUpdateCalls.Wait)
select {
case <-finished:
case <-time.After(5 * time.Second):
t.Fatalf("timed out waiting for status update calls to finish")
}
mockDriver.AssertExpectations(t)
}