WorkletSharedStorage: remainingBudget() method

{{APIRef("Shared Storage API")}}{{deprecated_header}}

The remainingBudget() method of the {{domxref("WorkletSharedStorage")}} interface returns the remaining navigation budget for the current origin.

The navigation budget is the number of entropy bits permitted inside a {{htmlelement("fencedframe")}} due to the {{domxref("WindowSharedStorage.selectURL()")}} calls per origin every 24 hours. This is not the same as the number of navigations; rather, it is based on the number of potential navigations in each call. Each time a selectURL() navigation occurs, the corresponding origin's budget decreases by the logarithm (base 2) of the number of URL choices.

Navigation budget is a mechanism designed to limit the rate of leakage of cross-site data to the destination pages navigated to in fenced frames.

Syntax

remainingBudget()

Parameters

None.

Return value

A {{jsxref("Promise")}} that fulfills with a number representing the remaining navigation budget.

Exceptions

• {{jsxref("TypeError")}}
  • : Thrown if the worklet module has not yet been added with {{domxref("Worklet.addModule", "addModule()")}} or if the calling site does not have the Shared Storage API included in a successful privacy sandbox enrollment process.

Examples

// remainingBudget() available inside a shared storage worklet module

async function retrieveBudget() {
  const budget = await this.sharedStorage.remainingBudget();
  console.log(budget);
}

Specifications

{{Specifications}}

Browser compatibility

{{Compat}}

See also

• Shared Storage API