Note: This feature is only available in Web Workers.
The fetch() method of the WorkerGlobalScope interface starts the process of fetching a resource from the network, returning a promise that is fulfilled once the response is available.
The promise resolves to the Response object representing the response to your request.
A fetch() promise only rejects when the request fails, for example, because of a badly-formed request URL or a network error. A fetch() promise does not reject if the server responds with HTTP status codes that indicate errors (404, 504, etc.). Instead, a then() handler must check the Response.ok and/or Response.status properties.
The fetch() method is controlled by the connect-src directive of Content Security Policy rather than the directive of the resources it's retrieving.
Note: The fetch() method's parameters are identical to those of the Request() constructor.
fetch(resource)
fetch(resource, options)resourceThis defines the resource that you wish to fetch. This can either be:
URL object — that provides the URL of the resource you want to fetch. The URL may be relative to the base URL, which is the document's baseURI in a window context, or WorkerGlobalScope.location in a worker context.Request object.options OptionalA RequestInit object containing any custom settings that you want to apply to the request.
A Promise that resolves to a Response object.
AbortError DOMExceptionThe request was aborted due to a call to the AbortController abort() method.
NotAllowedError DOMExceptionThrown if use of the Topics API is specifically disallowed by a browsing-topics Permissions Policy, and a fetch() request was made with browsingTopics: true.
TypeErrorAn error when the fetch operation could not be performed. See Window.fetch() exceptions for a list of reasons why this error can occur.
See fetch() for examples.