source

Documentation

Overview

Package source provides event streams to hook up to Controllers with Controller.Watch. Events are used with handler.EventHandlers to enqueue reconcile.Requests and trigger Reconciles for Kubernetes objects.

Index

• type Channel
  • func (cs *Channel) InjectStopChannel(stop <-chan struct{}) error
  • func (cs *Channel) Start(ctx context.Context, handler handler.EventHandler, ...) error
  • func (cs *Channel) String() string
• type Func
  • func (f Func) Start(ctx context.Context, evt handler.EventHandler, ...) error
  • func (f Func) String() string
• type Informer
  • func (is *Informer) Start(ctx context.Context, handler handler.EventHandler, ...) error
  • func (is *Informer) String() string
• type Kind
  • func (ks *Kind) InjectCache(c cache.Cache) error
  • func (ks *Kind) Start(ctx context.Context, handler handler.EventHandler, ...) error
  • func (ks *Kind) String() string
  • func (ks *Kind) WaitForSync(ctx context.Context) error
• type Source
• type SyncingSource
  • func NewKindWithCache(object client.Object, cache cache.Cache) SyncingSource

Examples

• Channel
• Kind

Types

type Channel

type Channel struct {

	// Source is the source channel to fetch GenericEvents
	Source <-chan event.GenericEvent

	// DestBufferSize is the specified buffer size of dest channels.
	// Default to 1024 if not specified.
	DestBufferSize int
	// contains filtered or unexported fields
}

Channel is used to provide a source of events originating outside the cluster (e.g. GitHub Webhook callback). Channel requires the user to wire the external source (eh.g. http handler) to write GenericEvents to the underlying channel.

Example

This example reads GenericEvents from a channel and enqueues a reconcile.Request containing the Name and Namespace provided by the event.

package main

import (
	"sigs.k8s.io/controller-runtime/pkg/controller"
	"sigs.k8s.io/controller-runtime/pkg/event"
	"sigs.k8s.io/controller-runtime/pkg/handler"
	"sigs.k8s.io/controller-runtime/pkg/source"
)

var ctrl controller.Controller

func main() {
	events := make(chan event.GenericEvent)

	err := ctrl.Watch(
		&source.Channel{Source: events},
		&handler.EnqueueRequestForObject{},
	)
	if err != nil {
		// handle it
	}
}

func (*Channel) InjectStopChannel

func (cs *Channel) InjectStopChannel(stop <-chan struct{}) error

InjectStopChannel is internal should be called only by the Controller. It is used to inject the stop channel initialized by the ControllerManager.

func (*Channel) Start

func (cs *Channel) Start(
	ctx context.Context,
	handler handler.EventHandler,
	queue workqueue.RateLimitingInterface,
	prct ...predicate.Predicate) error

Start implements Source and should only be called by the Controller.

func (*Channel) String

func (cs *Channel) String() string

type Func

type Func func(context.Context, handler.EventHandler, workqueue.RateLimitingInterface, ...predicate.Predicate) error

Func is a function that implements Source.

func (Func) Start

func (f Func) Start(ctx context.Context, evt handler.EventHandler, queue workqueue.RateLimitingInterface,
	pr ...predicate.Predicate) error

Start implements Source.

func (Func) String

func (f Func) String() string

type Informer

type Informer struct {
	// Informer is the controller-runtime Informer
	Informer cache.Informer
}

Informer is used to provide a source of events originating inside the cluster from Watches (e.g. Pod Create).

func (*Informer) Start

func (is *Informer) Start(ctx context.Context, handler handler.EventHandler, queue workqueue.RateLimitingInterface,
	prct ...predicate.Predicate) error

Start is internal and should be called only by the Controller to register an EventHandler with the Informer to enqueue reconcile.Requests.

func (*Informer) String

func (is *Informer) String() string

type Kind

type Kind struct {
	// Type is the type of object to watch.  e.g. &v1.Pod{}
	Type client.Object
	// contains filtered or unexported fields
}

Kind is used to provide a source of events originating inside the cluster from Watches (e.g. Pod Create).

Example

This example Watches for Pod Events (e.g. Create / Update / Delete) and enqueues a reconcile.Request with the Name and Namespace of the Pod.

package main

import (
	corev1 "k8s.io/api/core/v1"
	"sigs.k8s.io/controller-runtime/pkg/controller"
	"sigs.k8s.io/controller-runtime/pkg/handler"
	"sigs.k8s.io/controller-runtime/pkg/source"
)

var ctrl controller.Controller

func main() {
	err := ctrl.Watch(&source.Kind{Type: &corev1.Pod{}}, &handler.EnqueueRequestForObject{})
	if err != nil {
		// handle it
	}
}

func (*Kind) InjectCache

func (ks *Kind) InjectCache(c cache.Cache) error

InjectCache is internal should be called only by the Controller. InjectCache is used to inject the Cache dependency initialized by the ControllerManager.

func (*Kind) Start

func (ks *Kind) Start(ctx context.Context, handler handler.EventHandler, queue workqueue.RateLimitingInterface,
	prct ...predicate.Predicate) error

Start is internal and should be called only by the Controller to register an EventHandler with the Informer to enqueue reconcile.Requests.

func (*Kind) String

func (ks *Kind) String() string

func (*Kind) WaitForSync

func (ks *Kind) WaitForSync(ctx context.Context) error

WaitForSync implements SyncingSource to allow controllers to wait with starting workers until the cache is synced.

type Source

type Source interface {
	// Start is internal and should be called only by the Controller to register an EventHandler with the Informer
	// to enqueue reconcile.Requests.
	Start(context.Context, handler.EventHandler, workqueue.RateLimitingInterface, ...predicate.Predicate) error
}

Source is a source of events (eh.g. Create, Update, Delete operations on Kubernetes Objects, Webhook callbacks, etc) which should be processed by event.EventHandlers to enqueue reconcile.Requests.

* Use Kind for events originating in the cluster (e.g. Pod Create, Pod Update, Deployment Update).

* Use Channel for events originating outside the cluster (eh.g. GitHub Webhook callback, Polling external urls).

Users may build their own Source implementations. If their implementations implement any of the inject package interfaces, the dependencies will be injected by the Controller when Watch is called.

type SyncingSource

type SyncingSource interface {
	Source
	WaitForSync(ctx context.Context) error
}

SyncingSource is a source that needs syncing prior to being usable. The controller will call its WaitForSync prior to starting workers.

func NewKindWithCache

func NewKindWithCache(object client.Object, cache cache.Cache) SyncingSource

NewKindWithCache creates a Source without InjectCache, so that it is assured that the given cache is used and not overwritten. It can be used to watch objects in a different cluster by passing the cache from that other cluster.