Documentation
¶
Overview ¶
Package watch contains a generic watchable interface, and a fake for testing code that uses the watch interface.
Index ¶
- type Broadcaster
- type ConditionFunc
- 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 Recorder
- type StreamWatcher
Constants ¶
This section is empty.
Variables ¶
This section is empty.
Functions ¶
This section is empty.
Types ¶
type Broadcaster ¶ added in v0.7.0
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 ¶ added in v0.7.0
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 (*Broadcaster) Action ¶ added in v0.7.0
func (m *Broadcaster) Action(action EventType, obj runtime.Object)
Action distributes the given event among all watchers.
func (*Broadcaster) Shutdown ¶ added in v0.7.0
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.
func (*Broadcaster) Watch ¶ added in v0.7.0
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.
func (*Broadcaster) WatchWithPrefix ¶ added in v0.15.0
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.
type ConditionFunc ¶ added in v1.3.0
ConditionFunc returns true if the condition has been reached, false if it has not been reached yet, or an error if the condition cannot be checked and should terminate. In general, it is better to define level driven conditions over edge driven conditions (pod has ready=true, vs pod modified and ready changed from false to true).
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 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.
func Until ¶ added in v1.3.0
Until reads items from the watch until each provided condition succeeds, and then returns the last watch encountered. The first condition that returns an error terminates the watch (and the event is also returned). If no event has been received, the returned event will be nil. Conditions are satisfied sequentially so as to provide a useful primitive for higher level composition.
type FakeWatcher ¶
FakeWatcher lets you test anything that consumes a watch.Interface; threadsafe.
func NewFake ¶
func NewFake() *FakeWatcher
func NewFakeWithChanSize ¶ added in v1.4.2
func NewFakeWithChanSize(size int) *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 ¶ added in v1.4.2
func (f *FakeWatcher) IsStopped() bool
func (*FakeWatcher) Modify ¶
func (f *FakeWatcher) Modify(obj runtime.Object)
Modify sends a modify event.
func (*FakeWatcher) Reset ¶ added in v1.3.0
func (f *FakeWatcher) Reset()
Reset prepares the watcher to be reused.
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 ¶ added in v0.9.2
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, this channel will be closed, in which case the // watch should be completely cleaned up. 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 ¶ added in v0.8.0
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 Recorder ¶ added in v1.3.0
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 ¶ added in v1.3.0
NewRecorder wraps an Interface and records any changes sent across it.
type StreamWatcher ¶
StreamWatcher turns any stream for which you can write a Decoder interface into a watch.Interface.
func NewStreamWatcher ¶
func NewStreamWatcher(d Decoder) *StreamWatcher
NewStreamWatcher creates a StreamWatcher from the given decoder.
func (*StreamWatcher) ResultChan ¶
func (sw *StreamWatcher) ResultChan() <-chan Event
ResultChan implements Interface.
Directories
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Path | Synopsis |
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Package json implements a simple encoder and decoder for streams of watch events over io.Writer/Readers
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Package json implements a simple encoder and decoder for streams of watch events over io.Writer/Readers |
Package versioned is a generated protocol buffer package.
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Package versioned is a generated protocol buffer package. |