cache

Documentation

Overview

Package cache fingerprints a group's declared inputs and persists the result so unchanged groups can be skipped on subsequent runs.

Index

• func Compute(spec *config.Cache, command string, params []string) (string, error)
• func WritesPresent(spec *config.Cache) bool
• type Entry
• type FileStore
  • func NewFileStore(dir string) *FileStore
  • func (s *FileStore) Load(group string) (*Entry, bool)
  • func (s *FileStore) Save(group string, e *Entry) error
• type Store

Functions

func Compute

func Compute(spec *config.Cache, command string, params []string) (string, error)

Compute returns a content fingerprint for the given cache spec. The fingerprint changes when the method, command, params, or any matched input file changes. A glob that matches nothing contributes nothing, so adding the first matching file naturally changes the fingerprint.

func WritesPresent

func WritesPresent(spec *config.Cache) bool

WritesPresent reports whether every declared output glob matches at least one existing path. A missing output invalidates a would-be cache hit.

Types

type Entry

type Entry struct {
	Fingerprint string           `json:"fingerprint"`
	Result      result.RunResult `json:"result"`
	Command     string           `json:"command"`
	Params      []string         `json:"params"`
	UpdatedAt   time.Time        `json:"updatedAt"`
}

Entry is a persisted cache record for one group.

type FileStore

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

FileStore persists one JSON entry per group under a directory.

func NewFileStore

func NewFileStore(dir string) *FileStore

NewFileStore returns a store rooted at dir. The directory is created lazily on the first Save.

func (*FileStore) Load

func (s *FileStore) Load(group string) (*Entry, bool)

Load returns the stored entry for a group, or (nil, false) if absent or unreadable.

func (*FileStore) Save

func (s *FileStore) Save(group string, e *Entry) error

Save writes the entry for a group, creating the cache directory if needed.

type Store

type Store interface {
	Load(group string) (*Entry, bool)
	Save(group string, e *Entry) error
}

Store loads and saves cache entries keyed by group name.