cache

Documentation

Overview

Package cache provides the blob cache.

File name convention:

• blobs/sha256/*.tmp: tmp files

• blobs/sha256/<SHA256>: verified blobs

• metadata/sha256/<SHA256> : metadata of the blob (optional)

• digests/by-url-sha256/<SHA256-OF-URL> : digest of the blob (optional, note that URL is not always unique)

Index

• Constants
• func ValidateMetadata(m *Metadata) error
• type Cache
  • func New(dir string) (*Cache, error)
  • func (c *Cache) BlobAbsPath(sha256sum string) (string, error)
  • func (c *Cache) BlobRelPath(sha256sum string) (string, error)
  • func (c *Cache) Cached(sha256sum string) (bool, error)
  • func (c *Cache) Dir() string
  • func (c *Cache) Ensure(ctx context.Context, u *url.URL, sha256sum string, m *Metadata) error
  • func (c *Cache) Export(dir string) (map[string]string, error)
  • func (c *Cache) Import(dirOrFiles ...string) (map[string]string, error)
  • func (c *Cache) ImportWithReader(r io.Reader) (sha256sum string, err error)
  • func (c *Cache) ImportWithURL(u *url.URL, m *Metadata) (sha256sum string, err error)
  • func (c *Cache) MetadataBySHA256(sha256sum string) (*Metadata, error)
  • func (c *Cache) MetadataFileAbsPath(sha256sum string) (string, error)
  • func (c *Cache) MetadataFileRelPath(sha256sum string) (string, error)
  • func (c *Cache) ReverseURLFileAbsPath(u *url.URL) (string, error)
  • func (c *Cache) ReverseURLFileRelPath(u *url.URL) (string, error)
  • func (c *Cache) SHA256ByOriginURL(u *url.URL) (string, error)
• type Metadata

Constants

const (
	BlobsSHA256RelPath    = "blobs/sha256"
	MetadataSHA256RelPath = "metadata/sha256"
	ReverseURLRelPath     = "digests/by-url-sha256"
)

Functions

func ValidateMetadata

func ValidateMetadata(m *Metadata) error

Types

type Cache

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

func New

func New(dir string) (*Cache, error)

func (*Cache) BlobAbsPath

func (c *Cache) BlobAbsPath(sha256sum string) (string, error)

func (*Cache) BlobRelPath

func (c *Cache) BlobRelPath(sha256sum string) (string, error)

BlobRelPath returns a clean relative path like "blobs/sha256/<SHA256>". The caller should append this path to c.Dir(). The returned path may not exist. If it exists, its digest must have been already verified.

func (*Cache) Cached

func (c *Cache) Cached(sha256sum string) (bool, error)

func (*Cache) Dir

func (c *Cache) Dir() string

func (*Cache) Ensure

func (c *Cache) Ensure(ctx context.Context, u *url.URL, sha256sum string, m *Metadata) error

func (*Cache) Export

func (c *Cache) Export(dir string) (map[string]string, error)

func (*Cache) Import

func (c *Cache) Import(dirOrFiles ...string) (map[string]string, error)

Import imports local directories or files, and returns map[basename]sha256sum .

func (*Cache) ImportWithReader

func (c *Cache) ImportWithReader(r io.Reader) (sha256sum string, err error)

ImportWithReader imports from the reader. Does not create the metadata files.

func (*Cache) ImportWithURL

func (c *Cache) ImportWithURL(u *url.URL, m *Metadata) (sha256sum string, err error)

func (*Cache) MetadataBySHA256

func (c *Cache) MetadataBySHA256(sha256sum string) (*Metadata, error)

MetadataBySHA256 returns the metadata for the blob. Not always available.

func (*Cache) MetadataFileAbsPath

func (c *Cache) MetadataFileAbsPath(sha256sum string) (string, error)

func (*Cache) MetadataFileRelPath

func (c *Cache) MetadataFileRelPath(sha256sum string) (string, error)

func (*Cache) ReverseURLFileAbsPath

func (c *Cache) ReverseURLFileAbsPath(u *url.URL) (string, error)

func (*Cache) ReverseURLFileRelPath

func (c *Cache) ReverseURLFileRelPath(u *url.URL) (string, error)

func (*Cache) SHA256ByOriginURL

func (c *Cache) SHA256ByOriginURL(u *url.URL) (string, error)

SHA256ByOriginURL returns the sha256sum by the origin URL. Not always available. Do not use this unless you are sure that the URL is unique.

type Metadata

type Metadata struct {
	Basename string
}