cache

Documentation

Index

• type BlobCache
  • func NewDirectoryCache(directory string, config DirectoryCacheConfig) (BlobCache, error)
  • func NewMemoryCache() BlobCache
• type DirectoryCacheConfig
• type MemoryCache
  • func (mc *MemoryCache) Add(key string, opts ...Option) (Writer, error)
  • func (mc *MemoryCache) Close() error
  • func (mc *MemoryCache) Get(key string, opts ...Option) (Reader, error)
• type Option
  • func Direct() Option
• type Reader
• type Writer

Types

type BlobCache

type BlobCache interface {
	// Add returns a writer to add contents to cache
	Add(key string, opts ...Option) (Writer, error)

	// Get returns a reader to read the specified contents
	// from cache
	Get(key string, opts ...Option) (Reader, error)

	// Close closes the cache
	Close() error
}

BlobCache represents a cache for bytes data

func NewDirectoryCache

func NewDirectoryCache(directory string, config DirectoryCacheConfig) (BlobCache, error)

func NewMemoryCache

func NewMemoryCache() BlobCache

type DirectoryCacheConfig

type DirectoryCacheConfig struct {

	// Number of entries of LRU cache (default: 10).
	// This won't be used when DataCache is specified.
	MaxLRUCacheEntry int

	// Number of file descriptors to cache (default: 10).
	// This won't be used when FdCache is specified.
	MaxCacheFds int

	// On Add, wait until the data is fully written to the cache directory.
	SyncAdd bool

	// DataCache is an on-memory cache of the data.
	// OnEvicted will be overridden and replaced for internal use.
	DataCache *lrucache.Cache

	// FdCache is a cache for opened file descriptors.
	// OnEvicted will be overridden and replaced for internal use.
	FdCache *lrucache.Cache

	// BufPool will be used for pooling bytes.Buffer.
	BufPool *sync.Pool

	// Direct forcefully enables direct mode for all operation in cache.
	// Thus operation won't use on-memory caches.
	Direct bool
}

type MemoryCache

type MemoryCache struct {
	Membuf map[string]*bytes.Buffer
	// contains filtered or unexported fields
}

MemoryCache is a cache implementation which backend is a memory.

func (*MemoryCache) Add

func (mc *MemoryCache) Add(key string, opts ...Option) (Writer, error)

func (*MemoryCache) Close

func (mc *MemoryCache) Close() error

func (*MemoryCache) Get

func (mc *MemoryCache) Get(key string, opts ...Option) (Reader, error)

type Option

type Option func(o *cacheOpt) *cacheOpt

func Direct

func Direct() Option

Direct option lets FetchAt and Add methods not to use on-memory caches. When you know that the targeting value won't be used immediately, you can prevent the limited space of on-memory caches from being polluted by these unimportant values.

type Reader

type Reader interface {
	io.ReaderAt
	Close() error
}

Reader provides the data cached.

type Writer

type Writer interface {
	io.WriteCloser
	Commit() error
	Abort() error
}

Writer enables the client to cache byte data. Commit() must be called after data is fully written to Write(). To abort the written data, Abort() must be called.