watch

Documentation

Index

• Constants
• func DynamicResourceClient(dynamicClient dynamic.Interface, mapper meta.RESTMapper, ...) (dynamic.ResourceInterface, error)
• func ListAndWatch(ctx context.Context, lw ListerWatcher, opts metav1.ListOptions) (watch.Interface, error)
• func NewClientError(err error) *apierrors.StatusError
• type ListFunc
• type ListWatch
  • func NewFilteredListWatchFromClient(dynamicClient dynamic.Interface, mapper meta.RESTMapper, ...) *ListWatch
  • func NewListWatchFromClient(dynamicClient dynamic.Interface, mapper meta.RESTMapper, ...) *ListWatch
  • func (lw *ListWatch) List(ctx context.Context, options metav1.ListOptions) (*unstructured.UnstructuredList, error)
  • func (lw *ListWatch) Watch(ctx context.Context, options metav1.ListOptions) (watch.Interface, error)
• type Lister
• type ListerWatcher
• type ListerWatcherFactory
  • func NewListerWatcherFactoryFromClient(cfg *rest.Config) (ListerWatcherFactory, error)
• type Manager
  • func NewManager(scope declared.Scope, syncName string, cfg *rest.Config, q *queue.ObjectQueue, ...) (*Manager, error)
  • func (m *Manager) ManagementConflict() bool
  • func (m *Manager) NeedsUpdate() bool
  • func (m *Manager) UpdateWatches(ctx context.Context, gvkMap map[schema.GroupVersionKind]struct{}) status.MultiError
• type Options
  • func DefaultOptions(cfg *rest.Config) (*Options, error)
• type Runnable
  • func NewFiltered(cfg watcherConfig) Runnable
• type WatchFunc
• type Watcher

Constants

const (

	// RESTConfigTimeout sets the REST config timeout for the remediator to 1 hour.
	//
	// RESTConfigTimeout should be longer than 2*minWatchTimeout to respect
	// the watch timeout set by `ListOptions.TimeoutSeconds` in the watch
	// create requests.
	RESTConfigTimeout = time.Hour

	// ClientWatchDecodingCause is the status cause returned for client errors during response decoding.
	// https://github.com/kubernetes/client-go/blob/v0.26.7/rest/request.go#L785
	ClientWatchDecodingCause metav1.CauseType = "ClientWatchDecoding"

	// ContextCancelledCauseMessage is the error message from the DynamicClient
	// when the Watch method errors due to context cancellation.
	// https://github.com/kubernetes/apimachinery/blob/v0.26.7/pkg/watch/streamwatcher.go#L120
	ContextCancelledCauseMessage = "unable to decode an event from the watch stream: context canceled"
)

const StatusClientError = 600

StatusClientError is a "fake" HTTP status code used to indicate a client-side error. Normal status codes go from 1xx-5xx, so using 600 should be safe, unless Kubernetes starts using it.

const StatusReasonClientError metav1.StatusReason = "ClientError"

StatusReasonClientError is the reason used for client-side errors. It's the human readable form of the `StatusClientError` status code.

Functions

func DynamicResourceClient

func DynamicResourceClient(dynamicClient dynamic.Interface, mapper meta.RESTMapper, gvk schema.GroupVersionKind, namespace string) (dynamic.ResourceInterface, error)

DynamicResourceClient uses a generic dynamic.Interface to build a resource-specific client.

• For cluster-scoped resources, namespace must be empty.
• For namespace-scoped resources, namespace may optionally be empty, to include resources in all namespaces.

func ListAndWatch

func ListAndWatch(ctx context.Context, lw ListerWatcher, opts metav1.ListOptions) (watch.Interface, error)

ListAndWatch wraps a list and watch and returns a watch interface. This way, you can watch from "now" and get all the existing objects, not just new changes to objects.

If ResourceVersion is specified, ListAndWatch acts like a normal Watch. Otherwise, a List is performed first and `Added` events are simulated, followed by a Watch, where subsequent `Added` events for pre-existing objects are converted to `Modified` events, unless that object is deleted first.

func NewClientError

func NewClientError(err error) *apierrors.StatusError

NewClientError returns an error indicating that there was a client-side error. Unfortunately, the watch.Interface does not include a way to return client-side errors that preserves their error type. But at least this way we can tell the difference between a client-side error and a server-side error.

Types

type ListFunc

type ListFunc func(ctx context.Context, options metav1.ListOptions) (*unstructured.UnstructuredList, error)

ListFunc knows how to list resources.

type ListWatch

type ListWatch struct {
	ListFunc  ListFunc
	WatchFunc WatchFunc
}

ListWatch implements the ListerWatcher interface. ListFunc and WatchFunc must not be nil

func NewFilteredListWatchFromClient

func NewFilteredListWatchFromClient(dynamicClient dynamic.Interface, mapper meta.RESTMapper, gvk schema.GroupVersionKind, namespace string, optionsModifier func(options *metav1.ListOptions)) *ListWatch

NewFilteredListWatchFromClient creates a new ListWatch that can dynamically modify ListOptions. This allows specifying option defaults and overrides.

func NewListWatchFromClient

func NewListWatchFromClient(dynamicClient dynamic.Interface, mapper meta.RESTMapper, gvk schema.GroupVersionKind, namespace string) *ListWatch

NewListWatchFromClient creates a new ListWatch.

func (*ListWatch) List

func (lw *ListWatch) List(ctx context.Context, options metav1.ListOptions) (*unstructured.UnstructuredList, error)

List a set of apiserver resources

func (*ListWatch) Watch

func (lw *ListWatch) Watch(ctx context.Context, options metav1.ListOptions) (watch.Interface, error)

Watch a set of apiserver resources

type Lister

type Lister interface {
	// List returns a list of unstructured objects.
	// List can be cancelled with the input context.
	List(ctx context.Context, options metav1.ListOptions) (*unstructured.UnstructuredList, error)
}

Lister is any object that performs listing of a resource.

type ListerWatcher

type ListerWatcher interface {
	Lister
	Watcher
}

ListerWatcher is any object can perform both lists and watches. This is similar to the ListerWatcher in client-go, except it uses the dynamic client to return unstructured objects without requiring a local scheme.

type ListerWatcherFactory

type ListerWatcherFactory func(gvk schema.GroupVersionKind, namespace string) ListerWatcher

ListerWatcherFactory knows how to build ListerWatchers for the specified GroupVersionKind and Namespace.

func NewListerWatcherFactoryFromClient

func NewListerWatcherFactoryFromClient(cfg *rest.Config) (ListerWatcherFactory, error)

NewListerWatcherFactoryFromClient creates a ListerWatcherFactory using a dynamic client and mapper build from the specified REST config.

type Manager

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

Manager accepts new resource lists that are parsed from Git and then updates declared resources and get GVKs.

func NewManager

func NewManager(scope declared.Scope, syncName string, cfg *rest.Config,
	q *queue.ObjectQueue, decls *declared.Resources, options *Options, ch conflict.Handler) (*Manager, error)

NewManager starts a new watch manager

func (*Manager) ManagementConflict

func (m *Manager) ManagementConflict() bool

ManagementConflict returns true if any watcher notices any management conflicts. This function is threadsafe.

func (*Manager) NeedsUpdate

func (m *Manager) NeedsUpdate() bool

NeedsUpdate returns true if the Manager's watches need to be updated. This function is threadsafe.

func (*Manager) UpdateWatches

func (m *Manager) UpdateWatches(ctx context.Context, gvkMap map[schema.GroupVersionKind]struct{}) status.MultiError

UpdateWatches accepts a map of GVKs that should be watched and takes the following actions:

• stop watchers for any GroupVersionKind that is not present in the given map.
• start watchers for any GroupVersionKind that is present in the given map and not present in the current watch map.

This function is threadsafe.

type Options

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

Options contains options for creating a watch manager.

func DefaultOptions

func DefaultOptions(cfg *rest.Config) (*Options, error)

DefaultOptions return the default options with a ListerWatcherFactory built from the specified REST config.

type Runnable

type Runnable interface {
	Stop()
	Run(ctx context.Context) status.Error
	ManagementConflict() bool
	SetManagementConflict(object client.Object, commit string)
	ClearManagementConflict()
	// contains filtered or unexported methods
}

Runnable defines the custom watch interface.

func NewFiltered

func NewFiltered(cfg watcherConfig) Runnable

NewFiltered returns a new filtered watcher initialized with the given options.

type WatchFunc

type WatchFunc func(ctx context.Context, options metav1.ListOptions) (watch.Interface, error)

WatchFunc knows how to watch resources.

type Watcher

type Watcher interface {
	// Watch starts watching at the specified version.
	// List can be cancelled with the input context.
	Watch(ctx context.Context, options metav1.ListOptions) (watch.Interface, error)
}

Watcher is any object that performs watching of a resource.