Documentation ¶
Overview ¶
Package watch contains a generic watchable interface, and a fake for testing code that uses the watch interface.
Index ¶
- Variables
- type Broadcaster
- type Decoder
- type Event
- type EventType
- type FakeWatcher
- func (f *FakeWatcher) Action(action EventType, obj runtime.Object)
- func (f *FakeWatcher) Add(obj runtime.Object)
- func (f *FakeWatcher) Delete(lastValue runtime.Object)
- func (f *FakeWatcher) Error(errValue runtime.Object)
- func (f *FakeWatcher) IsStopped() bool
- func (f *FakeWatcher) Modify(obj runtime.Object)
- func (f *FakeWatcher) Reset()
- func (f *FakeWatcher) ResultChan() <-chan Event
- func (f *FakeWatcher) Stop()
- type FilterFunc
- type FullChannelBehavior
- type Interface
- type ProxyWatcher
- type RaceFreeFakeWatcher
- func (f *RaceFreeFakeWatcher) Action(action EventType, obj runtime.Object)
- func (f *RaceFreeFakeWatcher) Add(obj runtime.Object)
- func (f *RaceFreeFakeWatcher) Delete(lastValue runtime.Object)
- func (f *RaceFreeFakeWatcher) Error(errValue runtime.Object)
- func (f *RaceFreeFakeWatcher) IsStopped() bool
- func (f *RaceFreeFakeWatcher) Modify(obj runtime.Object)
- func (f *RaceFreeFakeWatcher) Reset()
- func (f *RaceFreeFakeWatcher) ResultChan() <-chan Event
- func (f *RaceFreeFakeWatcher) Stop()
- type Recorder
- type Reporter
- type StreamWatcher
Constants ¶
This section is empty.
Variables ¶
var (
DefaultChanSize int32 = 100
)
Functions ¶
This section is empty.
Types ¶
type Broadcaster ¶
type Broadcaster struct {
// contains filtered or unexported fields
}
Broadcaster distributes event notifications among any number of watchers. Every event is delivered to every watcher.
func NewBroadcaster ¶
func NewBroadcaster(queueLength int, fullChannelBehavior FullChannelBehavior) *Broadcaster
NewBroadcaster creates a new Broadcaster. queueLength is the maximum number of events to queue per watcher. It is guaranteed that events will be distributed in the order in which they occur, but the order in which a single event is distributed among all of the watchers is unspecified.
func NewLongQueueBroadcaster ¶
func NewLongQueueBroadcaster(queueLength int, fullChannelBehavior FullChannelBehavior) *Broadcaster
NewLongQueueBroadcaster functions nearly identically to NewBroadcaster, except that the incoming queue is the same size as the outgoing queues (specified by queueLength).
func (*Broadcaster) Action ¶
func (m *Broadcaster) Action(action EventType, obj runtime.Object)
Action distributes the given event among all watchers.
func (*Broadcaster) ActionOrDrop ¶
func (m *Broadcaster) ActionOrDrop(action EventType, obj runtime.Object) bool
Action distributes the given event among all watchers, or drops it on the floor if too many incoming actions are queued up. Returns true if the action was sent, false if dropped.
func (*Broadcaster) Shutdown ¶
func (m *Broadcaster) Shutdown()
Shutdown disconnects all watchers (but any queued events will still be distributed). You must not call Action or Watch* after calling Shutdown. This call blocks until all events have been distributed through the outbound channels. Note that since they can be buffered, this means that the watchers might not have received the data yet as it can remain sitting in the buffered channel. It will block until the broadcaster stop request is actually executed
func (*Broadcaster) Watch ¶
func (m *Broadcaster) Watch() Interface
Watch adds a new watcher to the list and returns an Interface for it. Note: new watchers will only receive new events. They won't get an entire history of previous events. It will block until the watcher is actually added to the broadcaster.
func (*Broadcaster) WatchWithPrefix ¶
func (m *Broadcaster) WatchWithPrefix(queuedEvents []Event) Interface
WatchWithPrefix adds a new watcher to the list and returns an Interface for it. It sends queuedEvents down the new watch before beginning to send ordinary events from Broadcaster. The returned watch will have a queue length that is at least large enough to accommodate all of the items in queuedEvents. It will block until the watcher is actually added to the broadcaster.
type Decoder ¶
type Decoder interface { // Decode should return the type of event, the decoded object, or an error. // An error will cause StreamWatcher to call Close(). Decode should block until // it has data or an error occurs. Decode() (action EventType, object runtime.Object, err error) // Close should close the underlying io.Reader, signalling to the source of // the stream that it is no longer being watched. Close() must cause any // outstanding call to Decode() to return with an error of some sort. Close() }
Decoder allows StreamWatcher to watch any stream for which a Decoder can be written.
type Event ¶
type Event struct { Type EventType // Object is: // * If Type is Added or Modified: the new state of the object. // * If Type is Deleted: the state of the object immediately before deletion. // * If Type is Bookmark: the object (instance of a type being watched) where // only ResourceVersion field is set. On successful restart of watch from a // bookmark resourceVersion, client is guaranteed to not get repeat event // nor miss any events. // * If Type is Error: *api.Status is recommended; other types may make sense // depending on context. Object runtime.Object }
Event represents a single event to a watched resource. +k8s:deepcopy-gen=true
func (*Event) DeepCopy ¶
DeepCopy is an autogenerated deepcopy function, copying the receiver, creating a new Event.
func (*Event) DeepCopyInto ¶
DeepCopyInto is an autogenerated deepcopy function, copying the receiver, writing into out. in must be non-nil.
type FakeWatcher ¶
FakeWatcher lets you test anything that consumes a watch.Interface; threadsafe.
func NewFake ¶
func NewFake() *FakeWatcher
func NewFakeWithChanSize ¶
func NewFakeWithChanSize(size int, blocking bool) *FakeWatcher
func (*FakeWatcher) Action ¶
func (f *FakeWatcher) Action(action EventType, obj runtime.Object)
Action sends an event of the requested type, for table-based testing.
func (*FakeWatcher) Delete ¶
func (f *FakeWatcher) Delete(lastValue runtime.Object)
Delete sends a delete event.
func (*FakeWatcher) Error ¶
func (f *FakeWatcher) Error(errValue runtime.Object)
Error sends an Error event.
func (*FakeWatcher) IsStopped ¶
func (f *FakeWatcher) IsStopped() bool
func (*FakeWatcher) Modify ¶
func (f *FakeWatcher) Modify(obj runtime.Object)
Modify sends a modify event.
func (*FakeWatcher) ResultChan ¶
func (f *FakeWatcher) ResultChan() <-chan Event
type FilterFunc ¶
FilterFunc should take an event, possibly modify it in some way, and return the modified event. If the event should be ignored, then return keep=false.
type FullChannelBehavior ¶
type FullChannelBehavior int
FullChannelBehavior controls how the Broadcaster reacts if a watcher's watch channel is full.
const ( WaitIfChannelFull FullChannelBehavior = iota DropIfChannelFull )
type Interface ¶
type Interface interface { // Stops watching. Will close the channel returned by ResultChan(). Releases // any resources used by the watch. Stop() // Returns a chan which will receive all the events. If an error occurs // or Stop() is called, the implementation will close this channel and // release any resources used by the watch. ResultChan() <-chan Event }
Interface can be implemented by anything that knows how to watch and report changes.
func Filter ¶
func Filter(w Interface, f FilterFunc) Interface
Filter passes all events through f before allowing them to pass on. Putting a filter on a watch, as an unavoidable side-effect due to the way go channels work, effectively causes the watch's event channel to have its queue length increased by one.
WARNING: filter has a fatal flaw, in that it can't properly update the Type field (Add/Modified/Deleted) to reflect items beginning to pass the filter when they previously didn't.
func NewEmptyWatch ¶
func NewEmptyWatch() Interface
NewEmptyWatch returns a watch interface that returns no results and is closed. May be used in certain error conditions where no information is available but an error is not warranted.
type ProxyWatcher ¶
type ProxyWatcher struct {
// contains filtered or unexported fields
}
ProxyWatcher lets you wrap your channel in watch Interface. threadsafe.
func NewProxyWatcher ¶
func NewProxyWatcher(ch chan Event) *ProxyWatcher
NewProxyWatcher creates new ProxyWatcher by wrapping a channel
func (*ProxyWatcher) ResultChan ¶
func (pw *ProxyWatcher) ResultChan() <-chan Event
ResultChan implements Interface
func (*ProxyWatcher) StopChan ¶
func (pw *ProxyWatcher) StopChan() <-chan struct{}
StopChan returns stop channel
func (*ProxyWatcher) Stopping ¶
func (pw *ProxyWatcher) Stopping() bool
Stopping returns true if Stop() has been called
type RaceFreeFakeWatcher ¶
type RaceFreeFakeWatcher struct { Stopped bool sync.Mutex // contains filtered or unexported fields }
RaceFreeFakeWatcher lets you test anything that consumes a watch.Interface; threadsafe.
func NewRaceFreeFake ¶
func NewRaceFreeFake() *RaceFreeFakeWatcher
func (*RaceFreeFakeWatcher) Action ¶
func (f *RaceFreeFakeWatcher) Action(action EventType, obj runtime.Object)
Action sends an event of the requested type, for table-based testing.
func (*RaceFreeFakeWatcher) Add ¶
func (f *RaceFreeFakeWatcher) Add(obj runtime.Object)
Add sends an add event.
func (*RaceFreeFakeWatcher) Delete ¶
func (f *RaceFreeFakeWatcher) Delete(lastValue runtime.Object)
Delete sends a delete event.
func (*RaceFreeFakeWatcher) Error ¶
func (f *RaceFreeFakeWatcher) Error(errValue runtime.Object)
Error sends an Error event.
func (*RaceFreeFakeWatcher) IsStopped ¶
func (f *RaceFreeFakeWatcher) IsStopped() bool
func (*RaceFreeFakeWatcher) Modify ¶
func (f *RaceFreeFakeWatcher) Modify(obj runtime.Object)
Modify sends a modify event.
func (*RaceFreeFakeWatcher) Reset ¶
func (f *RaceFreeFakeWatcher) Reset()
Reset prepares the watcher to be reused.
func (*RaceFreeFakeWatcher) ResultChan ¶
func (f *RaceFreeFakeWatcher) ResultChan() <-chan Event
func (*RaceFreeFakeWatcher) Stop ¶
func (f *RaceFreeFakeWatcher) Stop()
Stop implements Interface.Stop().
type Recorder ¶
type Recorder struct { Interface // contains filtered or unexported fields }
Recorder records all events that are sent from the watch until it is closed.
func NewRecorder ¶
NewRecorder wraps an Interface and records any changes sent across it.
type Reporter ¶
type Reporter interface { // AsObject must convert err into a valid runtime.Object for the watch stream. AsObject(err error) runtime.Object }
Reporter hides the details of how an error is turned into a runtime.Object for reporting on a watch stream since this package may not import a higher level report.
type StreamWatcher ¶
StreamWatcher turns any stream for which you can write a Decoder interface into a watch.Interface.
func NewStreamWatcher ¶
func NewStreamWatcher(d Decoder, r Reporter) *StreamWatcher
NewStreamWatcher creates a StreamWatcher from the given decoder.
func (*StreamWatcher) ResultChan ¶
func (sw *StreamWatcher) ResultChan() <-chan Event
ResultChan implements Interface.