cache

Documentation

Overview

Package cache implements an inmemory cache for any object.

Although exported, this package is non intended for general consumption. It is a shared dependency between multiple exposure notifications projects. We cannot guarantee that there won't be breaking changes in the future.

Index

• Variables
• type Cache
  • func New[T any](expireAfter time.Duration) (*Cache[T], error)
  • func (c *Cache[T]) Clear()
  • func (c *Cache[T]) Lookup(name string) (T, bool)
  • func (c *Cache[T]) Set(name string, object T) error
  • func (c *Cache[T]) Size() int
  • func (c *Cache[T]) Stop()
  • func (c *Cache[T]) WriteThruLookup(name string, primaryLookup Func[T]) (T, error)
• type Func

Variables

var ErrInvalidDuration = errors.New("expireAfter duration cannot be negative")

Types

type Cache

type Cache[T any] struct {
	// contains filtered or unexported fields
}

func New

func New[T any](expireAfter time.Duration) (*Cache[T], error)

New creates a new in memory cache.

func (*Cache[T]) Clear

func (c *Cache[T]) Clear()

Clear removes all items from the cache, regardless of their expiration.

func (*Cache[T]) Lookup

func (c *Cache[T]) Lookup(name string) (T, bool)

Lookup checks the cache for a non-expired object by the supplied key name. The bool return informs the caller if there was a cache hit or not. A return of nil, true means that nil is in the cache. Where nil, false indicates a cache miss or that the value is expired and should be refreshed.

func (*Cache[T]) Set

func (c *Cache[T]) Set(name string, object T) error

Set saves the current value of an object in the cache, with the supplied durintion until the object expires.

func (*Cache[T]) Size

func (c *Cache[T]) Size() int

Size returns the number of items in the cache.

func (*Cache[T]) Stop

func (c *Cache[T]) Stop()

Stop will shutdown the background cleanup for the cache.

func (*Cache[T]) WriteThruLookup

func (c *Cache[T]) WriteThruLookup(name string, primaryLookup Func[T]) (T, error)

WriteThruLookup checks the cache for the value associated with name, and if not found or expired, invokes the provided primaryLookup function to local the value.

type Func

type Func[T any] func() (T, error)