controller

Documentation

Overview

Package controller provides reusable support for controller implementations.

Index

• func RetryAlways(obj interface{}, err error, retries Retry) bool
• func RetryNever(obj interface{}, err error, retries Retry) bool
• type Queue
• type QueueRetryManager
  • func NewQueueRetryManager(queue ReQueue, keyFn kcache.KeyFunc, retryFn RetryFunc, ...) *QueueRetryManager
  • func (r *QueueRetryManager) Forget(resource interface{})
  • func (r *QueueRetryManager) Retry(resource interface{}, err error)
• type ReQueue
• type Retry
• type RetryController
  • func (c *RetryController) Run()
  • func (c *RetryController) RunUntil(stopCh <-chan struct{})
• type RetryFunc
• type RetryManager
• type RunnableController

Functions

func RetryAlways

func RetryAlways(obj interface{}, err error, retries Retry) bool

RetryNever is a RetryFunc implementation that will always retry

func RetryNever

func RetryNever(obj interface{}, err error, retries Retry) bool

RetryNever is a RetryFunc implementation that will never retry

Types

type Queue

type Queue interface {
	Pop() interface{}
}

Queue is a narrow abstraction of a cache.FIFO.

type QueueRetryManager

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

QueueRetryManager retries a resource by re-queueing it into a ReQueue as long as retryFunc returns true.

func NewQueueRetryManager

func NewQueueRetryManager(queue ReQueue, keyFn kcache.KeyFunc, retryFn RetryFunc, limiter kutil.RateLimiter) *QueueRetryManager

NewQueueRetryManager safely creates a new QueueRetryManager.

func (*QueueRetryManager) Forget

func (r *QueueRetryManager) Forget(resource interface{})

Forget resets the retry count for resource.

func (*QueueRetryManager) Retry

func (r *QueueRetryManager) Retry(resource interface{}, err error)

Retry will enqueue resource until retryFunc returns false for that resource has been exceeded, at which point resource will be forgotten and no longer retried. The current retry count will be passed to each invocation of retryFunc.

type ReQueue

type ReQueue interface {
	Queue
	AddIfNotPresent(interface{}) error
}

ReQueue is a queue that allows an object to be requeued

type Retry

type Retry struct {
	// Count is the number of retries
	Count int

	// StartTimestamp is retry start timestamp
	StartTimestamp kutil.Time
}

Retry describes provides additional information regarding retries.

type RetryController

type RetryController struct {
	// Queue is where work is retrieved for Handle.
	Queue

	// Handle is expected to process the next resource from the queue.
	Handle func(interface{}) error

	// RetryManager is fed the handled resource if Handle returns a Retryable
	// error. If Handle returns no error, the RetryManager is asked to forget
	// the resource.
	RetryManager
}

RetryController is a RunnableController which delegates resource handling to a function and knows how to safely manage retries of a resource which failed to be successfully handled.

func (*RetryController) Run

func (c *RetryController) Run()

Run begins processing resources from Queue asynchronously.

func (*RetryController) RunUntil

func (c *RetryController) RunUntil(stopCh <-chan struct{})

RunUntil begins processing resources from Queue asynchronously until stopCh is closed.

type RetryFunc

type RetryFunc func(obj interface{}, err error, retries Retry) bool

RetryFunc should return true if the given object and error should be retried after the provided number of times.

type RetryManager

type RetryManager interface {
	// Retry will cause resource processing to be retried (for example, by
	// requeueing resource)
	Retry(resource interface{}, err error)

	// Forget will cause the manager to erase all prior knowledge of resource
	// and reclaim internal resources associated with state tracking of
	// resource.
	Forget(resource interface{})
}

RetryManager knows how to retry processing of a resource, and how to forget a resource it may be tracking the state of.

type RunnableController

type RunnableController interface {
	// Run starts the asynchronous controller loop.
	Run()
}

RunnableController is a controller which implements a Run loop.