cache

Documentation

Index

• type Backend
  • func NewInMemoryCache() Backend
• type Entry
• type FileBackend
  • func NewFileBackend(baseDir string) *FileBackend
  • func (*FileBackend) Flush() error
  • func (fb *FileBackend) Get(key string) (entry *Entry, found bool)
  • func (fb *FileBackend) Purge(key string) error
  • func (*FileBackend) PurgeTags(tags []string) error
  • func (fb *FileBackend) Set(key string, entry *Entry) error
• type HTTPFrontend
  • func GetHTTPFrontendCacheWithNullBackend() *HTTPFrontend
  • func (hf *HTTPFrontend) Get(ctx context.Context, key string, loader HTTPLoader) (*http.Response, error)
  • func (hf *HTTPFrontend) Inject(backend Backend, logger flamingo.Logger)
• type HTTPLoader
• type Meta
• type NullBackend
  • func (*NullBackend) Flush() error
  • func (*NullBackend) Get(key string) (entry *Entry, found bool)
  • func (*NullBackend) Purge(key string) error
  • func (*NullBackend) PurgeTags(tags []string) error
  • func (*NullBackend) Set(key string, entry *Entry) error
• type StringFrontend
  • func (sf *StringFrontend) Get(key string, loader StringLoader) (string, error)
  • func (sf *StringFrontend) Inject(backend Backend)
• type StringLoader

Types

type Backend

type Backend interface {
	Get(key string) (entry *Entry, found bool) // Get a cache entry
	Set(key string, entry *Entry) error        // Set a cache entry
	//Peek(key string) (entry *CacheEntry, found bool) // Peek for a cache entry, this should not trigger key-updates or weight/priorities to be changed
	Purge(key string) error
	PurgeTags(tags []string) error
	Flush() error
}

Backend describes a cache backend, responsible for storing, flushing, setting and getting entries

func NewInMemoryCache

func NewInMemoryCache() Backend

NewInMemoryCache creates a new lru TwoQueue backed cache backend

type Entry

type Entry struct {
	Meta Meta
	Data interface{}
}

Entry is a cached object with associated meta data

type FileBackend

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

FileBackend is a cache backend which saves the data in files

func NewFileBackend

func NewFileBackend(baseDir string) *FileBackend

NewFileBackend returns a FileBackend operating in the given baseDir

func (*FileBackend) Flush

func (*FileBackend) Flush() error

Flush is not supported by FileBackend and does nothing

func (*FileBackend) Get

func (fb *FileBackend) Get(key string) (entry *Entry, found bool)

Get reads a cache entry

func (*FileBackend) Purge

func (fb *FileBackend) Purge(key string) error

Purge deletes a cache entry

func (*FileBackend) PurgeTags

func (*FileBackend) PurgeTags(tags []string) error

PurgeTags is not supported by FileBackend and does nothing

func (*FileBackend) Set

func (fb *FileBackend) Set(key string, entry *Entry) error

Set writes a cache entry

type HTTPFrontend

type HTTPFrontend struct {
	singleflight.Group
	// contains filtered or unexported fields
}

HTTPFrontend stores and caches http responses

func GetHTTPFrontendCacheWithNullBackend

func GetHTTPFrontendCacheWithNullBackend() *HTTPFrontend

GetHTTPFrontendCacheWithNullBackend helper for tests

func (*HTTPFrontend) Get

func (hf *HTTPFrontend) Get(ctx context.Context, key string, loader HTTPLoader) (*http.Response, error)

Get a http response, with tags and a loader the tags will be used when the entry is stored

func (*HTTPFrontend) Inject

func (hf *HTTPFrontend) Inject(backend Backend, logger flamingo.Logger)

Inject HTTPFrontend dependencies

type HTTPLoader

type HTTPLoader func(context.Context) (*http.Response, *Meta, error)

HTTPLoader returns a response. it will be cached unless there is an error. this means 400/500 responses are cached too!

type Meta

type Meta struct {
	Tags                []string
	Lifetime, Gracetime time.Duration
	// contains filtered or unexported fields
}

Meta describes life and gracetimes, as well as tags, for cache entries

type NullBackend

type NullBackend struct{}

NullBackend does not store anything

func (*NullBackend) Flush

func (*NullBackend) Flush() error

Flush nothing

func (*NullBackend) Get

func (*NullBackend) Get(key string) (entry *Entry, found bool)

Get nothing

func (*NullBackend) Purge

func (*NullBackend) Purge(key string) error

Purge nothing

func (*NullBackend) PurgeTags

func (*NullBackend) PurgeTags(tags []string) error

PurgeTags purges nothing

func (*NullBackend) Set

func (*NullBackend) Set(key string, entry *Entry) error

Set nothing

type StringFrontend

type StringFrontend struct {
	singleflight.Group
	// contains filtered or unexported fields
}

StringFrontend manages cache entries as strings

func (*StringFrontend) Get

func (sf *StringFrontend) Get(key string, loader StringLoader) (string, error)

Get and load string cache entries

func (*StringFrontend) Inject

func (sf *StringFrontend) Inject(backend Backend)

Inject StringFrontend dependencies

type StringLoader

type StringLoader func() (string, *Meta, error)

StringLoader is used to load strings for singleflight cache loads