Utility for caching files in Netlify Build.

Examples

Simple

// Restore file/directory cached in previous builds.
// Does not do anything if:
//  - the file/directory already exists locally
//  - the file/directory has not been cached yet
export const onPreBuild = async function ({ utils }) {
  await utils.cache.restore('./path/to/file')
}

// Cache file/directory for future builds.
// Does not do anything if:
//  - the file/directory does not exist locally
export const onPostBuild = async function ({ utils }) {
  await utils.cache.save('./path/to/file')
}

Multiple directories

// Restore/cache several files/directories
export const onPreBuild = async function ({ utils }) {
  await utils.cache.restore(['./path/to/file', './path/to/other'])
}

export const onPostBuild = async function ({ utils }) {
  await utils.cache.save(['./path/to/file', './path/to/other'])
}

API

save(path, options?)

path: string
options: object
Returns: Promise<Boolean>

Cache a file/directory.

Skipped if the file/directory does not exist locally.

Returns false if the file/directory does not exist. Returns true otherwise.

options

ttl

Type: number (in seconds)
Default: undefined

Only cache the file/directory for a specific amount of time.

// Only cache the following file/directory for 1 hour
export const onPreBuild = async function ({ utils }) {
  await utils.cache.restore('./path/to/file')
}

export const onPostBuild = async function ({ utils }) {
  const ttl = 3600
  await utils.cache.save('./path/to/file', { ttl })
}

digests

Type: string[]
Default: []

Paths to lock files or manifest files that can be used to check if the directory to cache has changed. Using this option speeds up caching.

// If that directory has a lockfile or a manifest file, use it to check if its
// contents has changed. This will speed up cache saving.
// For example, `package-lock.json` and `yarn.lock` are digest files for the
// `node_modules` directory.
export const onPreBuild = async function ({ utils }) {
  await utils.cache.restore('node_modules')
}

export const onPostBuild = async function ({ utils }) {
  await utils.cache.save('node_modules', {
    digests: ['package-lock.json', 'yarn.lock'],
  })
}

cwd

Type: string
Default: process.cwd()

Current directory used to resolve relative paths.

restore(path, options?)

path: string
options: object
Returns: Promise<Boolean>

Restore a file/directory previously cached. Skipped if the file/directory already exists locally or if it has not been cached yet.

Please be careful: this overwrites the local file/directory if any exists.

Returns false if the file/directory was not cached yet. Returns true otherwise.

options

cwd

Type: string
Default: process.cwd()

Current directory used to resolve relative paths.

remove(path, options?)

path: string
Returns: Promise<Boolean>

Remove a file/directory from the cache. Useful for cache invalidation.

Returns false if the file/directory was not cached yet. Returns true otherwise.

export const onPostBuild = async function ({ utils }) {
  await utils.cache.remove('./path/to/file')
}

options

cwd

Type: string
Default: process.cwd()

Current directory used to resolve relative paths.

has(path, options?)

path: string
Returns: Promise<Boolean>

Returns whether a file/directory is currently cached.

// Conditional logic can be applied depending on whether the file has been
// previously cached or not
const path = './path/to/file'

export const onPreBuild = async function ({ utils }) {
  if (!(await utils.cache.has(path))) {
    console.log(`File ${path} not cached`)
    return
  }

  console.log(`About to restore cached file ${path}...`)
  if (await utils.cache.restore('./path/to/file')) {
    console.log(`Restored cached file ${path}`)
  }
}

export const onPostBuild = async function ({ utils }) {
  if (await utils.cache.save('./path/to/file')) {
    console.log(`Saved cached file ${path}`)
  }
}

options

cwd

Type: string
Default: process.cwd()

Current directory used to resolve relative paths.

list(options?)

Returns: Promise<string[]>

Returns the absolute paths of the files currently cached. Those are the paths of the files before being saved (or after being restored), not while being cached.

export const onPreBuild = async function ({ utils }) {
  const files = await utils.cache.list()
  console.log('Cached files', files)
}

options

cwd

Type: string
Default: process.cwd()

Current directory used to resolve relative paths.

depth

Type: number
Default: 1

Number of subdirectories to include. 0 means only top-level directories will be included.