Module: workbox-build

Methods

copyWorkboxLibraries

static

copyWorkboxLibraries(destDirectory) returns Promise containing string

This copies over a set of runtime libraries used by Workbox into a local directory, which should be deployed alongside your service worker file.

As an alternative to deploying these local copies, you could instead use Workbox from its official CDN URL.

This method is exposed for the benefit of developers using injectManifest() who would prefer not to use the CDN copies of Workbox. Developers using generateSW() don't need to explicitly call this method.

Parameter
destDirectory	string The path to the parent directory under which the new directory of libraries will be created.

Parameter

destDirectory

string

The path to the parent directory under which the new directory of libraries will be created.

Returns: Promise containing string The name of the newly created directory.

generateSW

async static

generateSW(config) returns Promise containing {count: number, filePaths: Array of string, size: number, warnings: Array of string}

This method creates a list of URLs to precache, referred to as a "precache manifest", based on the options you provide.

It also takes in additional options that configures the service worker's behavior, like any runtimeCaching rules it should use.

Based on the precache manifest and the additional configuration, it writes a ready-to-use service worker file to disk at swDest.

Parameter

config

Object

The configuration to use.

Values in config have the following properties:

Parameter
globDirectory	string The local directory you wish to match `globPatterns` against. The path is relative to the current directory.
swDest	string The path and filename of the service worker file that will be created by the build process, relative to the current working directory. It must end in '.js'.
additionalManifestEntries	Optional Array of module:workbox-build.ManifestEntry A list of entries to be precached, in addition to any entries that are generated as part of the build configuration.
babelPresetEnvTargets	Optional Array of string The targets to pass to `babel-preset-env` when transpiling the service worker bundle.
cacheId	Optional string An optional ID to be prepended to cache names. This is primarily useful for local development where multiple sites may be served from the same `http://localhost:port` origin.
cleanupOutdatedCaches	Optional boolean Whether or not Workbox should attempt to identify an delete any precaches created by older, incompatible versions.
clientsClaim	Optional boolean Whether or not the service worker should start controlling any existing clients as soon as it activates.
directoryIndex	Optional string If a navigation request for a URL ending in `/` fails to match a precached URL, this value will be appended to the URL and that will be checked for a precache match. This should be set to what your web server is using for its directory index.
dontCacheBustURLsMatching	Optional RegExp Assets that match this will be assumed to be uniquely versioned via their URL, and exempted from the normal HTTP cache-busting that's done when populating the precache. While not required, it's recommended that if your existing build process already inserts a `[hash]` value into each filename, you provide a RegExp that will detect that, as it will reduce the bandwidth consumed when precaching.
globFollow	Optional boolean Determines whether or not symlinks are followed when generating the precache manifest. For more information, see the definition of `follow` in the `glob` documentation.
globIgnores	Optional Array of string A set of patterns matching files to always exclude when generating the precache manifest. For more information, see the definition of `ignore` in the `glob` documentation.
globPatterns	Optional Array of string Files matching any of these patterns will be included in the precache manifest. For more information, see the `glob` primer.
globStrict	Optional boolean If true, an error reading a directory when generating a precache manifest will cause the build to fail. If false, the problematic directory will be skipped. For more information, see the definition of `strict` in the `glob` documentation.
ignoreURLParametersMatching	Optional Array of RegExp Any search parameter names that match against one of the RegExp in this array will be removed before looking for a precache match. This is useful if your users might request URLs that contain, for example, URL parameters used to track the source of the traffic.
importScripts	Optional Array of string A list of JavaScript files that should be passed to `importScripts()` inside the generated service worker file. This is useful when you want to let Workbox create your top-level service worker file, but want to include some additional code, such as a push event listener.
inlineWorkboxRuntime	Optional boolean Whether the runtime code for the Workbox library should be included in the top-level service worker, or split into a separate file that needs to be deployed alongside the service worker. Keeping the runtime separate means that users will not have to re-download the Workbox code each time your top-level service worker changes.
manifestTransforms	Optional Array of module:workbox-build.ManifestTransform One or more functions which will be applied sequentially against the generated manifest. If `modifyURLPrefix` or `dontCacheBustURLsMatching` are also specified, their corresponding transformations will be applied first.
maximumFileSizeToCacheInBytes	Optional number This value can be used to determine the maximum size of files that will be precached. This prevents you from inadvertently precaching very large files that might have accidentally matched one of your patterns.
mode	Optional string If set to 'production', then an optimized service worker bundle that excludes debugging info will be produced. If not explicitly configured here, the `process.env.NODE_ENV` value will be used, and failing that, it will fall back to `'production'`.
modifyURLPrefix	Optional Object with string properties A mapping of prefixes that, if present in an entry in the precache manifest, will be replaced with the corresponding value. This can be used to, for example, remove or add a path prefix from a manifest entry if your web hosting setup doesn't match your local filesystem setup. As an alternative with more flexibility, you can use the `manifestTransforms` option and provide a function that modifies the entries in the manifest using whatever logic you provide.
navigateFallback	Optional string If specified, all navigation requests for URLs that aren't precached will be fulfilled with the HTML at the URL provided. You must pass in the URL of an HTML document that is listed in your precache manifest. This is meant to be used in a Single Page App scenario, in which you want all navigations to use common App Shell HTML.
navigateFallbackDenylist	Optional Array of RegExp An optional array of regular expressions that restricts which URLs the configured `navigateFallback` behavior applies to. This is useful if only a subset of your site's URLs should be treated as being part of a Single Page App. If both `navigateFallbackDenylist` and `navigateFallbackAllowlist` are configured, the denylist takes precedent.
navigateFallbackAllowlist	Optional Array of RegExp An optional array of regular expressions that restricts which URLs the configured `navigateFallback` behavior applies to. This is useful if only a subset of your site's URLs should be treated as being part of a Single Page App. If both `navigateFallbackDenylist` and `navigateFallbackAllowlist` are configured, the denylist takes precedent.
navigationPreload	Optional boolean Whether or not to enable navigation preload in the generated service worker. When set to true, you must also use `runtimeCaching` to set up an appropriate response strategy that will match navigation requests, and make use of the preloaded response.
offlineGoogleAnalytics	Optional (boolean or Object) Controls whether or not to include support for offline Google Analytics. When `true`, the call to `workbox-google-analytics`'s `initialize()` will be added to your generated service worker. When set to an `Object`, that object will be passed in to the `initialize()` call, allowing you to customize the behavior.
runtimeCaching	Optional Array of RuntimeCachingEntry
skipWaiting	Optional boolean Whether to add an unconditional call to `skipWaiting()` to the generated service worker. If `false`, then a `message` listener will be added instead, allowing you to conditionally call `skipWaiting()`.
sourcemap	Optional boolean Whether to create a sourcemap for the generated service worker files.
templatedURLs	Optional Object If a URL is rendered based on some server-side logic, its contents may depend on multiple files or on some other unique string value. The keys in this object are server-rendered URLs. If the values are an array of strings, they will be interpreted as `glob` patterns, and the contents of any files matching the patterns will be used to uniquely version the URL. If used with a single string, it will be interpreted as unique versioning information that you've generated for a given URL.

Returns: Promise containing {count: number, filePaths: Array of string, size: number, warnings: Array of string} A promise that resolves once the service worker and related files (indicated by filePaths) has been written to swDest. The size property contains the aggregate size of all the precached entries, in bytes, and the count property contains the total number of precached entries. Any non-fatal warning messages will be returned via warnings.

getManifest

async static

getManifest(config) returns Promise containing {count: number, filePaths: Array of string, size: number, warnings: Array of string}

This method returns a list of URLs to precache, referred to as a "precache manifest", along with details about the number of entries and their size, based on the options you provide.

Parameter

config

Object

The configuration to use.

Values in config have the following properties:

Parameter
globDirectory	string The local directory you wish to match `globPatterns` against. The path is relative to the current directory.
additionalManifestEntries	Optional Array of module:workbox-build.ManifestEntry A list of entries to be precached, in addition to any entries that are generated as part of the build configuration.
dontCacheBustURLsMatching	Optional RegExp Assets that match this will be assumed to be uniquely versioned via their URL, and exempted from the normal HTTP cache-busting that's done when populating the precache. While not required, it's recommended that if your existing build process already inserts a `[hash]` value into each filename, you provide a RegExp that will detect that, as it will reduce the bandwidth consumed when precaching.
globFollow	Optional boolean Determines whether or not symlinks are followed when generating the precache manifest. For more information, see the definition of `follow` in the `glob` documentation.
globIgnores	Optional Array of string A set of patterns matching files to always exclude when generating the precache manifest. For more information, see the definition of `ignore` in the `glob` documentation.
globPatterns	Optional Array of string Files matching any of these patterns will be included in the precache manifest. For more information, see the `glob` primer.
globStrict	Optional boolean If true, an error reading a directory when generating a precache manifest will cause the build to fail. If false, the problematic directory will be skipped. For more information, see the definition of `strict` in the `glob` documentation.
manifestTransforms	Optional Array of module:workbox-build.ManifestTransform One or more functions which will be applied sequentially against the generated manifest. If `modifyURLPrefix` or `dontCacheBustURLsMatching` are also specified, their corresponding transformations will be applied first.
maximumFileSizeToCacheInBytes	Optional number This value can be used to determine the maximum size of files that will be precached. This prevents you from inadvertently precaching very large files that might have accidentally matched one of your patterns.
mode	Optional string If set to 'production', then an optimized service worker bundle that excludes debugging info will be produced. If not explicitly configured here, the `process.env.NODE_ENV` value will be used, and failing that, it will fall back to `'production'`.
modifyURLPrefix	Optional Object with string properties A mapping of prefixes that, if present in an entry in the precache manifest, will be replaced with the corresponding value. This can be used to, for example, remove or add a path prefix from a manifest entry if your web hosting setup doesn't match your local filesystem setup. As an alternative with more flexibility, you can use the `manifestTransforms` option and provide a function that modifies the entries in the manifest using whatever logic you provide.
templatedURLs	Optional Object If a URL is rendered based on some server-side logic, its contents may depend on multiple files or on some other unique string value. The keys in this object are server-rendered URLs. If the values are an array of strings, they will be interpreted as `glob` patterns, and the contents of any files matching the patterns will be used to uniquely version the URL. If used with a single string, it will be interpreted as unique versioning information that you've generated for a given URL.

Returns: Promise containing {count: number, filePaths: Array of string, size: number, warnings: Array of string} A promise that resolves once the service worker and related files (indicated by filePaths) has been written to swDest. The size property contains the aggregate size of all the precached entries, in bytes, and the count property contains the total number of precached entries. Any non-fatal warning messages will be returned via warnings.

injectManifest

async static

injectManifest(config) returns Promise containing {count: number, filePaths: Array of string, size: number, warnings: Array of string}

This method creates a list of URLs to precache, referred to as a "precache manifest", based on the options you provide.

The manifest is injected into the swSrc file, and the placeholder string injectionPoint determines where in the file the manifest should go.

The final service worker file, with the manifest injected, is written to disk at swDest.

Parameter

config

Object

The configuration to use.

Values in config have the following properties:

Parameter
globDirectory	string The local directory you wish to match `globPatterns` against. The path is relative to the current directory.
swDest	string The path and filename of the service worker file that will be created by the build process, relative to the current working directory. It must end in '.js'.
swSrc	string The path and filename of the service worker file that will be read during the build process, relative to the current working directory.
additionalManifestEntries	Optional Array of module:workbox-build.ManifestEntry A list of entries to be precached, in addition to any entries that are generated as part of the build configuration.
dontCacheBustURLsMatching	Optional RegExp Assets that match this will be assumed to be uniquely versioned via their URL, and exempted from the normal HTTP cache-busting that's done when populating the precache. While not required, it's recommended that if your existing build process already inserts a `[hash]` value into each filename, you provide a RegExp that will detect that, as it will reduce the bandwidth consumed when precaching.
globFollow	Optional boolean Determines whether or not symlinks are followed when generating the precache manifest. For more information, see the definition of `follow` in the `glob` documentation.
globIgnores	Optional Array of string A set of patterns matching files to always exclude when generating the precache manifest. For more information, see the definition of `ignore` in the `glob` documentation.
globPatterns	Optional Array of string Files matching any of these patterns will be included in the precache manifest. For more information, see the `glob` primer.
globStrict	Optional boolean If true, an error reading a directory when generating a precache manifest will cause the build to fail. If false, the problematic directory will be skipped. For more information, see the definition of `strict` in the `glob` documentation.
injectionPoint	Optional string The string to find inside of the `swSrc` file. Once found, it will be replaced by the generated precache manifest.
manifestTransforms	Optional Array of module:workbox-build.ManifestTransform One or more functions which will be applied sequentially against the generated manifest. If `modifyURLPrefix` or `dontCacheBustURLsMatching` are also specified, their corresponding transformations will be applied first.
maximumFileSizeToCacheInBytes	Optional number This value can be used to determine the maximum size of files that will be precached. This prevents you from inadvertently precaching very large files that might have accidentally matched one of your patterns.
mode	Optional string If set to 'production', then an optimized service worker bundle that excludes debugging info will be produced. If not explicitly configured here, the `process.env.NODE_ENV` value will be used, and failing that, it will fall back to `'production'`.
modifyURLPrefix	Optional Object with string properties A mapping of prefixes that, if present in an entry in the precache manifest, will be replaced with the corresponding value. This can be used to, for example, remove or add a path prefix from a manifest entry if your web hosting setup doesn't match your local filesystem setup. As an alternative with more flexibility, you can use the `manifestTransforms` option and provide a function that modifies the entries in the manifest using whatever logic you provide.
templatedURLs	Optional Object If a URL is rendered based on some server-side logic, its contents may depend on multiple files or on some other unique string value. The keys in this object are server-rendered URLs. If the values are an array of strings, they will be interpreted as `glob` patterns, and the contents of any files matching the patterns will be used to uniquely version the URL. If used with a single string, it will be interpreted as unique versioning information that you've generated for a given URL.

Returns: Promise containing {count: number, filePaths: Array of string, size: number, warnings: Array of string} A promise that resolves once the service worker and related files (indicated by filePaths) has been written to swDest. The size property contains the aggregate size of all the precached entries, in bytes, and the count property contains the total number of precached entries. Any non-fatal warning messages will be returned via warnings.

Abstract types

ManifestEntry

static

Object

Properties

Parameter
url	string The URL to the asset in the manifest.
revision	Optional string The revision details for the file. This is a hash generated by node based on the file contents.
integrity	Optional string Integrity metadata that will be used when making the network request for the URL.

Parameter

url

string

The URL to the asset in the manifest.

revision

Optional

string

The revision details for the file. This is a hash generated by node based on the file contents.

integrity

Optional

string

Integrity metadata that will be used when making the network request for the URL.

ManifestTransform

static

ManifestTransform(manifestEntries, compilation) returns Promise containing module:workbox-build.ManifestTransformResult

A ManifestTransform function can be used to modify the modify the url or revision properties of some or all of the ManifestEntries in the manifest.

Deleting the revision property of an entry will cause the corresponding url to be precached without cache-busting parameters applied, which is to say, it implies that the URL itself contains proper versioning info. If the revision property is present, it must be set to a string.

Parameter
manifestEntries	Array of module:workbox-build.ManifestEntry The full array of entries, prior to the current transformation.
compilation	Optional Object When used in the webpack plugins, this param will be set to the current `compilation`.

Parameter

manifestEntries

Array of module:workbox-build.ManifestEntry

The full array of entries, prior to the current transformation.

compilation

Optional

Object

When used in the webpack plugins, this param will be set to the current compilation.

Returns: Promise containing module:workbox-build.ManifestTransformResult The array of entries with the transformation applied, and optionally, any warnings that should be reported back to the build tool.

Examples

A transformation that prepended the origin of a CDN for any
URL starting with '/assets/' could be implemented as:

const cdnTransform = async (manifestEntries) => {
  const manifest = manifestEntries.map(entry => {
    const cdnOrigin = 'https://example.com';
    if (entry.url.startsWith('/assets/')) {
      entry.url = cdnOrigin + entry.url;
    }
    return entry;
  });
  return {manifest, warnings: []};
};

A transformation that nulls the revision field when the
URL contains an 8-character hash surrounded by '.', indicating that it
already contains revision information:

const removeRevisionTransform = async (manifestEntries) => {
  const manifest = manifestEntries.map(entry => {
    const hashRegExp = /\.\w{8}\./;
    if (entry.url.match(hashRegExp)) {
      entry.revision = null;
    }
    return entry;
  });
  return {manifest, warnings: []};
};

ManifestTransformResult

static

Object

Properties

Parameter
manifest	Array of module:workbox-build.ManifestEntry
warnings	(Array of string or undefined)

RuntimeCachingEntry

static

Object

Properties

Parameter

handler

(string or module:workbox-routing~handlerCallback)

Either the name of one of the built-in strategy classes, or custom handler callback to use when the generated route matches.

urlPattern

(string, RegExp, or module:workbox-routing~matchCallback)

The value that will be passed to registerRoute(), used to determine whether the generated route will match a given request.

method

Optional

string

The HTTP method that will match the generated route.

options

Optional

Object

Values in options have the following properties:

Parameter
backgroundSync	Optional Object
backgroundSync.name	Optional string The `name` property to use when creating the `BackgroundSyncPlugin`.
backgroundSync.options	Optional Object The `options` property to use when creating the `BackgroundSyncPlugin`.
broadcastUpdate	Optional Object
broadcastUpdate.channelName	Optional string The `channelName` property to use when creating the `BroadcastCacheUpdatePlugin`.
broadcastUpdate.options	Optional Object The `options` property to use when creating the `BroadcastCacheUpdatePlugin`.
cacheableResponse	Optional Object
cacheableResponse.headers	Optional Object The `headers` property to use when creating the `CacheableResponsePlugin`.
cacheableResponse.statuses	Optional Array of number `statuses` property to use when creating the `CacheableResponsePlugin`.
cacheName	Optional string The `cacheName` to use when constructing one of the Workbox strategy classes.
fetchOptions	Optional Object The `fetchOptions` property value to use when constructing one of the Workbox strategy classes.
expiration	Optional Object
expiration.maxAgeSeconds	Optional number The `maxAgeSeconds` property to use when creating the `ExpirationPlugin`.
expiration.maxEntries	Optional number The `maxAgeSeconds` property to use when creating the `ExpirationPlugin`.
matchOptions	Optional Object The `matchOptions` property value to use when constructing one of the Workbox strategy classes.
networkTimeoutSeconds	Optional number The `networkTimeoutSeconds` property value to use when creating a `NetworkFirst` strategy.
plugins	Optional Array of Object One or more additional plugins to apply to the handler. Useful when you want a plugin that doesn't have a "shortcut" configuration.