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httpcache

package

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Versions in this module

v0

v0.8.0

Jan 27, 2026

Changes in this version

+ const DefaultCacheTTL

+ const DefaultCleanupInterval

+ const DefaultMaxCacheSize

+ const DefaultStaleMapTTL

+ func SetLogger(log *logger.Logger)

+ type CacheConfig struct

+ CleanupInterval time.Duration

+ MaxSize int64

+ StaleMapTTL time.Duration

+ TTL time.Duration

+ func DefaultCacheConfig() *CacheConfig

+ func (c *CacheConfig) Validate() *CacheConfig

+ func (c *CacheConfig) WithCleanupInterval(interval time.Duration) *CacheConfig

+ func (c *CacheConfig) WithMaxSize(size int64) *CacheConfig

+ func (c *CacheConfig) WithStaleMapTTL(ttl time.Duration) *CacheConfig

+ func (c *CacheConfig) WithTTL(ttl time.Duration) *CacheConfig

+ type CacheMetrics struct

+ ActiveConnections prometheus.Gauge

+ AuthFailures *prometheus.CounterVec

+ BytesTransferred *prometheus.CounterVec

+ CacheCleanupDuration prometheus.Histogram

+ CacheEvictions *prometheus.CounterVec

+ CacheHits *prometheus.CounterVec

+ CacheItemCount prometheus.Gauge

+ CacheMisses *prometheus.CounterVec

+ CacheRetrieveOperations *prometheus.CounterVec

+ CacheSizeBytes prometheus.Gauge

+ CacheSkips prometheus.Counter

+ CacheStaleCount prometheus.Gauge

+ CacheStoreOperations *prometheus.CounterVec

+ MirrorBenchmarkDuration *prometheus.HistogramVec

+ MirrorSwitches *prometheus.CounterVec

+ PackageDownloads *prometheus.CounterVec

+ RequestLatency *prometheus.HistogramVec

+ RequestsByDistro *prometheus.CounterVec

+ UpstreamDuration *prometheus.HistogramVec

+ UpstreamErrors *prometheus.CounterVec

+ var DefaultMetrics *CacheMetrics

+ func NewCacheMetrics(registry *metrics.Registry) *CacheMetrics

+ func (m *CacheMetrics) DecrementActiveConnections()

+ func (m *CacheMetrics) IncrementActiveConnections()

+ func (m *CacheMetrics) RecordAuthFailure(reason string)

+ func (m *CacheMetrics) RecordBytesTransferred(direction, distro string, bytes int64)

+ func (m *CacheMetrics) RecordCacheEviction(reason string)

+ func (m *CacheMetrics) RecordCacheHit(method string)

+ func (m *CacheMetrics) RecordCacheMiss(method string)

+ func (m *CacheMetrics) RecordCacheSkip()

+ func (m *CacheMetrics) RecordCleanupDuration(durationSeconds float64)

+ func (m *CacheMetrics) RecordMirrorBenchmarkDuration(distro, result string, durationSeconds float64)

+ func (m *CacheMetrics) RecordMirrorSwitch(distro, fromMirror, toMirror string)

+ func (m *CacheMetrics) RecordPackageDownload(distro, packageType string)

+ func (m *CacheMetrics) RecordRequestByDistro(distro, status string)

+ func (m *CacheMetrics) RecordRequestLatency(distro string, cacheHit bool, durationSeconds float64)

+ func (m *CacheMetrics) RecordRetrieveOperation(found bool)

+ func (m *CacheMetrics) RecordStoreOperation(success bool)

+ func (m *CacheMetrics) RecordUpstreamDuration(method string, status int, durationSeconds float64)

+ func (m *CacheMetrics) RecordUpstreamError(errorType string)

+ func (m *CacheMetrics) SetCacheItemCount(count int)

+ func (m *CacheMetrics) SetCacheSize(sizeBytes int64)

+ func (m *CacheMetrics) SetCacheStaleCount(count int)

+ func (m *CacheMetrics) UpdateCacheStats(stats CacheStats)

+ type CacheStats struct

+ HitCount int64

+ ItemCount int

+ MissCount int64

+ StaleCount int

+ TotalSize int64

+ type CleanupResult struct

+ Duration time.Duration

+ RemovedBytes int64

+ RemovedItems int

+ RemovedStaleEntries int

+ type ExtendedCache interface

+ Cleanup func() CleanupResult

+ Close func() error

+ Purge func() error

+ Stats func() CacheStats

+ func NewDiskCacheWithConfig(dir string, config *CacheConfig) (ExtendedCache, error)

+ func NewMemoryCacheWithConfig(config *CacheConfig) ExtendedCache

+ func NewVFSCacheWithConfig(fs vfs.VFS, config *CacheConfig) ExtendedCache

type Handler

+ func (h *Handler) SetMetrics(m *CacheMetrics)

v0.7.0

Nov 7, 2025

v0.6.0

Dec 1, 2024

v0.5.3

Nov 30, 2022

v0.5.2

Nov 20, 2022

v0.5.1

Nov 19, 2022

v0.5.0

Nov 19, 2022

v0.4.0

Nov 19, 2022

v0.3.3

Oct 10, 2022

Changes in this version

+ const CacheControlHeader

+ const CacheHeader

+ const ProxyDateHeader

+ var Clock = func() time.Time

+ var DebugLogging = false

+ var ErrNotFoundInCache = errors.New("not found in cache")

+ var Writes sync.WaitGroup

+ type Cache interface

+ Freshen func(res *Resource, keys ...string) error

+ Header func(key string) (Header, error)

+ Invalidate func(keys ...string)

+ Retrieve func(key string) (*Resource, error)

+ Store func(res *Resource, keys ...string) error

+ func NewDiskCache(dir string) (Cache, error)

+ func NewMemoryCache() Cache

+ func NewVFSCache(fs vfs.VFS) Cache

+ type CacheControl map[string][]string

+ func ParseCacheControl(input string) (CacheControl, error)

+ func ParseCacheControlHeaders(h http.Header) (CacheControl, error)

+ func (cc CacheControl) Add(key, val string)

+ func (cc CacheControl) Duration(key string) (time.Duration, error)

+ func (cc CacheControl) Get(key string) (string, bool)

+ func (cc CacheControl) Has(key string) bool

+ func (cc CacheControl) String() string

+ type Handler struct

+ Shared bool

+ func NewHandler(cache Cache, upstream http.Handler) *Handler

+ func (h *Handler) ServeHTTP(rw http.ResponseWriter, r *http.Request)

+ type Header struct

+ StatusCode int

+ type Key struct

+ func NewKey(method string, u *url.URL, h http.Header) Key

+ func NewRequestKey(r *http.Request) Key

+ func (k Key) ForMethod(method string) Key

+ func (k Key) String() string

+ func (k Key) Vary(varyHeader string, r *http.Request) Key

+ type ReadSeekCloser interface

+ type Resource struct

+ RequestTime time.Time

+ ResponseTime time.Time

+ func NewResource(statusCode int, body ReadSeekCloser, hdrs http.Header) *Resource

+ func NewResourceBytes(statusCode int, b []byte, hdrs http.Header) *Resource

+ func (r *Resource) Age() (time.Duration, error)

+ func (r *Resource) DateAfter(d time.Time) bool

+ func (r *Resource) Expires() (time.Time, error)

+ func (r *Resource) HasExplicitExpiration() bool

+ func (r *Resource) HasValidators() bool

+ func (r *Resource) Header() http.Header

+ func (r *Resource) HeuristicFreshness() time.Duration

+ func (r *Resource) IsNonErrorStatus() bool

+ func (r *Resource) IsStale() bool

+ func (r *Resource) LastModified() time.Time

+ func (r *Resource) MarkStale()

+ func (r *Resource) MaxAge(shared bool) (time.Duration, error)

+ func (r *Resource) MustValidate(shared bool) bool

+ func (r *Resource) RemovePrivateHeaders()

+ func (r *Resource) Status() int

+ func (r *Resource) Via() string

+ type Validator struct

+ Handler http.Handler

+ func (v *Validator) Validate(req *http.Request, res *Resource) bool