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) 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 Source
• type SyncingSource
  • func Kind(cache cache.Cache, object client.Object) 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) 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 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.

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 Kind

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

Kind creates a KindSource with the given cache provider.

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/manager"
	"sigs.k8s.io/controller-runtime/pkg/source"
)

var mgr manager.Manager
var ctrl controller.Controller

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