WorkerGlobalScope interface of the Web Workers API is an interface representing the scope of any worker. Workers have no browsing context; this scope contains the information usually conveyed by
Window objects — in this case event handlers, the console or the associated
WorkerNavigator object. Each
WorkerGlobalScope has its own event loop.
This interface is usually specialized by each worker type:
DedicatedWorkerGlobalScope for dedicated workers,
SharedWorkerGlobalScope for shared workers, and
ServiceWorkerGlobalScope for ServiceWorker. The
self property returns the specialized scope for each context.
This interface inherits properties from the
CacheStorageobject associated with the current context. This object enables functionality such as storing assets for offline use, and generating custom responses to requests.
Returns a boolean value that indicates whether the website is in a cross-origin isolation state.
Cryptoobject associated to the global object.
FontFaceSetassociated with the worker.
Provides a mechanism for applications to asynchronously access capabilities of indexed databases; returns an
Returns a boolean indicating whether the current context is secure (
true) or not (
Returns the global object's origin, serialized as a string.
Performanceassociated with the worker. It is a regular performance object, except that only a subset of its property and methods are available to workers.
This interface inherits methods from the
Decodes a string of data which has been encoded using base-64 encoding.
Creates a base-64 encoded ASCII string from a string of binary data.
Cancels the repeated execution set using
Cancels the delayed execution set using
Accepts a variety of different image sources, and returns a
Promisewhich resolves to an
ImageBitmap. Optionally the source is cropped to the rectangle of pixels originating at (sx, sy) with width sw, and height sh.
Starts the process of fetching a resource from the network.
Imports one or more scripts into the worker's scope. You can specify as many as you'd like, separated by commas. For example:
Queues a microtask to be executed at a safe time prior to control returning to the browser's event loop.
Schedules a function to execute every time a given number of milliseconds elapses.
Schedules a function to execute in a given amount of time.
Reports an error in a script, emulating an unhandled exception.
Fired when an error occurred.
Fired at the global/worker scope object when the user's preferred languages change.
Fired when the browser has lost access to the network and the value of
Fired when the browser has gained access to the network and the value of
Fired on handled
Fired when a Content Security Policy is violated.
Fired on unhandled
You won't access
WorkerGlobalScope directly in your code; however, its properties and methods are inherited by more specific global scopes such as
SharedWorkerGlobalScope. For example, you could import another script into the worker and print out the contents of the worker scope's
navigator object using the following two lines:
Note: Since the global scope of the worker script is effectively the global scope of the worker you are running (
DedicatedWorkerGlobalScope or whatever) and all worker global scopes inherit methods, properties, etc. from
WorkerGlobalScope, you can run lines such as those above without specifying a parent object.
BCD tables only load in the browser