luci: go.chromium.org/luci/common/data/caching/cache Index | Files

package cache

import "go.chromium.org/luci/common/data/caching/cache"

Package cache implements both in-memory and on-disk caching.

Index

Package Files

cache.go doc.go lru.go

type Cache Uses

type Cache interface {
    io.Closer

    // Keys returns the list of all cached digests in LRU order.
    Keys() isolated.HexDigests

    // Touch updates the LRU position of an item to ensure it is kept in the
    // cache.
    //
    // Returns true if item is in cache.
    Touch(digest isolated.HexDigest) bool

    // Evict removes item from cache if it's there.
    Evict(digest isolated.HexDigest)

    // Add reads data from src and stores it in cache.
    Add(digest isolated.HexDigest, src io.Reader) error

    // Read returns contents of the cached item.
    Read(digest isolated.HexDigest) (io.ReadCloser, error)

    // Hardlink ensures file at |dest| has the same content as cached |digest|.
    //
    // Note that the behavior when dest already exists is undefined. It will work
    // on all POSIX and may or may not fail on Windows depending on the
    // implementation used. Do not rely on this behavior.
    Hardlink(digest isolated.HexDigest, dest string, perm os.FileMode) error
}

Cache is a cache of objects.

All implementations must be thread-safe.

func NewDisk Uses

func NewDisk(policies Policies, path, namespace string) (Cache, error)

NewDisk creates a disk based cache.

It may return both a valid Cache and an error if it failed to load the previous cache metadata. It is safe to ignore this error.

func NewMemory Uses

func NewMemory(policies Policies, namespace string) Cache

NewMemory creates a purely in-memory cache.

type Policies Uses

type Policies struct {
    // MaxSize trims if the cache gets larger than this value. If 0, the cache is
    // effectively a leak.
    MaxSize units.Size
    // MaxItems is the maximum number of items to keep in the cache. If 0, do not
    // enforce a limit.
    MaxItems int
    // MinFreeSpace trims if disk free space becomes lower than this value. If 0,
    // it unconditionally fills the disk. Only makes sense when using disk based
    // cache.
    //
    // BUG: Implement Policies.MinFreeSpace.
    MinFreeSpace units.Size
}

Policies is the policies to use on a cache to limit it's footprint.

It's a cache, not a leak.

Package cache imports 14 packages (graph). Updated 2019-04-20. Refresh now. Tools for package owners.