contour

Documentation

Overview

Package contour contains the translation business logic that listens to Kubernetes ResourceEventHandler events and translates those into additions/deletions in caches connected to the Envoy xDS gRPC API server.

Package contour contains the translation business logic that listens to Kubernetes ResourceEventHandler events and translates those into additions/deletions in caches connected to the Envoy xDS gRPC API server.

Index

• type Cond
  • func (c *Cond) Notify(hints ...string)
  • func (c *Cond) Register(ch chan int, last int, hints ...string)
• type EventHandler
  • func (e *EventHandler) OnAdd(obj interface{})
  • func (e *EventHandler) OnDelete(obj interface{})
  • func (e *EventHandler) OnUpdate(oldObj, newObj interface{})
  • func (e *EventHandler) Start() func(<-chan struct{}) error
  • func (e *EventHandler) UpdateNow()
• type EventRecorder
  • func (e *EventRecorder) OnAdd(obj interface{})
  • func (e *EventRecorder) OnDelete(obj interface{})
  • func (e *EventRecorder) OnUpdate(oldObj, newObj interface{})
• type Observer
  • func ComposeObservers(observers ...Observer) Observer
• type ObserverFunc
  • func (f ObserverFunc) Refresh()
• type RebuildMetricsObserver
  • func (m *RebuildMetricsObserver) OnChange(d *dag.DAG)

Examples

• Cond

Types

type Cond

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

Cond implements a condition variable, a rendezvous point for goroutines waiting for or announcing the ocurence of an event.

Unlike sync.Cond, Cond communciates with waiters via channels registered by the waiters. This permits goroutines to wait on Cond events using select.

Example

ctx, cancel := context.WithTimeout(context.Background(), 1*time.Second)
defer cancel()
ch := make(chan int, 1)
last := 0
var c Cond
go func() {
	for {
		time.Sleep(100 * time.Millisecond)
		c.Notify()
	}
}()

for {
	c.Register(ch, last)
	select {
	case last = <-ch:
		fmt.Println("notification received:", last)
	case <-ctx.Done():
		fmt.Println("timeout")
		return
	}
}

func (*Cond) Notify

func (c *Cond) Notify(hints ...string)

Notify notifies all interested waiters that an event has ocured.

func (*Cond) Register

func (c *Cond) Register(ch chan int, last int, hints ...string)

Register registers ch to receive a value when Notify is called. The value of last is the count of the times Notify has been called on this Cond. It functions of a sequence counter, if the value of last supplied to Register is less than the Conds internal counter, then the caller has missed at least one notification and will fire immediately.

Sends by the broadcaster to ch must not block, therefore ch must have a capacity of at least 1.

type EventHandler

type EventHandler struct {
	Builder  dag.Builder
	Observer dag.Observer

	HoldoffDelay, HoldoffMaxDelay time.Duration

	StatusUpdater k8s.StatusUpdater

	logrus.FieldLogger

	// IsLeader will become ready to read when this EventHandler becomes
	// the leader. If IsLeader is not readable, or nil, status events will
	// be suppressed.
	IsLeader chan struct{}

	// Sequence is a channel that receives a incrementing sequence number
	// for each update processed. The updates may be processed immediately, or
	// delayed by a holdoff timer. In each case a non blocking send to Sequence
	// will be made once the resource update is received (note
	// that the DAG is not guaranteed to be called each time).
	Sequence chan int
	// contains filtered or unexported fields
}

EventHandler implements cache.ResourceEventHandler, filters k8s events towards a dag.Builder and calls through to the Observer to notify it that a new DAG is available.

func (*EventHandler) OnAdd

func (e *EventHandler) OnAdd(obj interface{})

func (*EventHandler) OnDelete

func (e *EventHandler) OnDelete(obj interface{})

func (*EventHandler) OnUpdate

func (e *EventHandler) OnUpdate(oldObj, newObj interface{})

func (*EventHandler) Start

func (e *EventHandler) Start() func(<-chan struct{}) error

Start initializes the EventHandler and returns a function suitable for registration with a workgroup.Group.

func (*EventHandler) UpdateNow

func (e *EventHandler) UpdateNow()

UpdateNow enqueues a DAG update subject to the holdoff timer.

type EventRecorder

type EventRecorder struct {
	Next    cache.ResourceEventHandler
	Counter *prometheus.CounterVec
}

EventRecorder records the count and kind of events forwarded to another ResourceEventHandler.

func (*EventRecorder) OnAdd

func (e *EventRecorder) OnAdd(obj interface{})

func (*EventRecorder) OnDelete

func (e *EventRecorder) OnDelete(obj interface{})

func (*EventRecorder) OnUpdate

func (e *EventRecorder) OnUpdate(oldObj, newObj interface{})

type Observer

type Observer interface {
	Refresh()
}

Observer is an interface for receiving notifications.

func ComposeObservers

func ComposeObservers(observers ...Observer) Observer

ComposeObservers returns a new Observer that calls each of its arguments in turn.

type ObserverFunc

type ObserverFunc func()

ObserverFunc is a function that implements the Observer interface by calling itself. It can be nil.

func (ObserverFunc) Refresh

func (f ObserverFunc) Refresh()

type RebuildMetricsObserver

type RebuildMetricsObserver struct {
	// Metrics to emit.
	Metrics *metrics.Metrics

	// IsLeader will become ready to read when this EventHandler becomes
	// the leader. If IsLeader is not readable, or nil, status events will
	// be suppressed.
	IsLeader chan struct{}

	// NextObserver contains the stack of dag.Observers that act on DAG rebuilds.
	NextObserver dag.Observer
}

RebuildMetricsObserver is a dag.Observer that emits metrics for DAG rebuilds.

func (*RebuildMetricsObserver) OnChange

func (m *RebuildMetricsObserver) OnChange(d *dag.DAG)