BackgroundFetchRegistration.md

BackgroundFetchRegistration

Namespace: SpawnDev.SpawnJS.JSObjects
Inherits: EventTarget
Source: JSObjects/BackgroundFetchRegistration.cs
MDN Reference: BackgroundFetchRegistration on MDN

The BackgroundFetchRegistration interface of the Background Fetch API represents an individual background fetch. A BackgroundFetchRegistration instance is returned by the BackgroundFetchManager.fetch() or BackgroundFetchManager.get() methods, and therefore there has no constructor. https://developer.mozilla.org/en-US/docs/Web/API/BackgroundFetchRegistration

Properties

Property	Type	Access	Description
Id	string	get	A string containing the background fetch's ID.
UploadTotal	long	get	A number containing the total number of bytes to be uploaded.
Uploaded	long	get/set	A number containing the size in bytes successfully sent, initially 0.
DownoadTotal	long	get	A number containing the total size in bytes of this download. This is the value set when the background fetch was registered, or 0.
Downoaded	long	get	A number containing the size in bytes that has been downloaded, initially 0.
Result	string	get	Returns an empty string initially, on completion either the string "success" or "failure".
FailureReason	string?	get/set	A string with a value that indicates a reason for a background fetch failure. Can be one of the following values: "", "aborted", "bad-status", "fetch-error", "quota-exceeded", "download-total-exceeded".
RecordsAvailable	bool	get	A boolean indicating whether the recordsAvailable flag is set.

Methods

Method	Return Type	Description
Abort()	Task<bool>	Aborts the background fetch. Returns a Promise that resolves with true if the fetch was successfully aborted.
Match(string request, BackgroundFetchMatchOptions options)	Task<BackgroundFetchRecord>	Returns a single BackgroundFetchRecord object which is the first match for the arguments.
Match(Request request)	Task<BackgroundFetchRecord>	Returns a single BackgroundFetchRecord object which is the first match for the arguments.
Match(Request request, BackgroundFetchMatchOptions options)	Task<BackgroundFetchRecord>	Returns a single BackgroundFetchRecord object which is the first match for the arguments.
Match(string request)	Task<BackgroundFetchRecord>	Returns a single BackgroundFetchRecord object which is the first match for the arguments.
MatchAll()	Task<BackgroundFetchRecord[]>	Returns a Promise that resolves with an array of BackgroundFetchRecord objects containing requests and responses.
MatchAll(Request request)	Task<BackgroundFetchRecord[]>	Returns a Promise that resolves with an array of BackgroundFetchRecord objects containing requests and responses.
MatchAll(Request request, BackgroundFetchMatchOptions options)	Task<BackgroundFetchRecord[]>	Returns a Promise that resolves with an array of BackgroundFetchRecord objects containing requests and responses.
MatchAll(string request)	Task<BackgroundFetchRecord[]>	Returns a Promise that resolves with an array of BackgroundFetchRecord objects containing requests and responses.
MatchAll(string request, BackgroundFetchMatchOptions options)	Task<BackgroundFetchRecord[]>	Returns a Promise that resolves with an array of BackgroundFetchRecord objects containing requests and responses.

Events

Event	Type	Description
OnProgress	ActionEvent<Event>	Fired when there is a change to any of the following properties: uploaded, downloaded, result or failureReason.

Examples

SpawnDev.SpawnJS Mapping Note: The JavaScript examples below show the standard Web API usage. In SpawnDev.SpawnJS, the same API is available with C# conventions:

• Properties and methods use PascalCase (e.g., readyState becomes ReadyState)
• Events use ActionEvent with +=/-= (e.g., addEventListener("click", fn) becomes OnClick += handler)
• Async methods return Task<T> instead of Promise<T>
• Objects should be disposed with using statements
• Access via JS.Get<BackgroundFetchRegistration>(...) or constructor new BackgroundFetchRegistration(...)

navigator.serviceWorker.ready.then(async (swReg) => {
  const bgFetch = await swReg.backgroundFetch.fetch(
    "my-fetch",
    ["/ep-5.mp3", "ep-5-artwork.jpg"],
    {
      title: "Episode 5: Interesting things.",
      icons: [
        {
          sizes: "300x300",
          src: "/ep-5-icon.png",
          type: "image/png",
        },
      ],
      downloadTotal: 60 * 1024 * 1024,
    },
  );
});

console.log(bgFetch.id); // "my-fetch"

bgFetch.match("/ep-5.mp3").then(async (record) => {
  if (!record) {
    console.log("No record found");
    return;
  }

  console.log(`Here's the request`, record.request);
  const response = await record.responseReady;
  console.log(`And here's the response`, response);
});

See full example on MDN