StorageManager: persist() method

Secure context

The persist() method of the StorageManager interface requests permission to use persistent storage, and returns a Promise that resolves to true if permission is granted and bucket mode is persistent, and false otherwise. The browser may or may not honor the request, depending on browser-specific rules. (For more details, see the guide to Storage quotas and eviction criteria.)

[!NOTE] This method is not available in Web Workers, though the StorageManager interface is.

Syntax

persist()

Parameters

None.

Return value

A Promise that resolves to a Boolean.

Exceptions

• TypeError
  • : Thrown if obtaining a local storage shelf failed. For example, if the current origin is an opaque origin or if the user has disabled storage.

Example

if (navigator.storage && navigator.storage.persist) {
  navigator.storage.persist().then((persistent) => {
    if (persistent) {
      console.log("Storage will not be cleared except by explicit user action");
    } else {
      console.log("Storage may be cleared by the UA under storage pressure.");
    }
  });
}

Specifications

Browser compatibility