pleg

type GenericPLEG ¶

type GenericPLEG struct {
	// contains filtered or unexported fields
}

GenericPLEG is an extremely simple generic PLEG that relies solely on periodic listing to discover container changes. It should be be used as temporary replacement for container runtimes do not support a proper event generator yet.

Note that GenericPLEG assumes that a container would not be created, terminated, and garbage collected within one relist period. If such an incident happens, GenenricPLEG would miss all events regarding this container. In the case of relisting failure, the window may become longer. Note that this assumption is not unique -- many kubelet internal components rely on terminated containers as tombstones for bookkeeping purposes. The garbage collector is implemented to work with such situtations. However, to guarantee that kubelet can handle missing container events, it is recommended to set the relist period short and have an auxiliary, longer periodic sync in kubelet as the safety net.

func (g *GenericPLEG) Start()

func (g *GenericPLEG) Watch() chan *PodLifecycleEvent

type PodLifeCycleEventType ¶

type PodLifeCycleEventType string

const (
	ContainerStarted      PodLifeCycleEventType = "ContainerStarted"
	ContainerDied         PodLifeCycleEventType = "ContainerDied"
	NetworkSetupCompleted PodLifeCycleEventType = "NetworkSetupCompleted"
	NetworkFailed         PodLifeCycleEventType = "NetworkFailed"
	// PodSync is used to trigger syncing of a pod when the observed change of
	// the state of the pod cannot be captured by any single event above.
	PodSync PodLifeCycleEventType = "PodSync"
)

type PodLifecycleEvent ¶

type PodLifecycleEvent struct {
	// The pod ID.
	ID types.UID
	// The type of the event.
	Type PodLifeCycleEventType
	// The accompanied data which varies based on the event type.
	//   - ContainerStarted/ContainerStopped: the container name (string).
	//   - All other event types: unused.
	Data interface{}
}

PodLifecycleEvent is an event that reflects the change of the pod state.

type PodLifecycleEventGenerator ¶

type PodLifecycleEventGenerator interface {
	Start()
	Watch() chan *PodLifecycleEvent
}

func NewGenericPLEG(runtime kubecontainer.Runtime, channelCapacity int,
	relistPeriod time.Duration) PodLifecycleEventGenerator