SharedStorage: append() method
Deprecated
To be removed
This feature is pending removal from browsers. Using it now may lead to broken functionality in future updates. Following the announcement that Chrome will maintain its current approach to third-party cookies, Chrome decided to withdraw certain Privacy Sandbox features including the shared storage.
Non-standard: This feature is not standardized. We do not recommend using non-standard features in production, as they have limited browser support, and may change or be removed. However, they can be a suitable alternative in specific cases where no standard option exists.
The append() method of the SharedStorage interface appends a string to the value of an existing key-value pair in the current origin's shared storage.
Syntax
append(key, value)
Parameters
key-
A string representing the key of the key-value pair to which you want to append a value.
value-
A string that you want to append to the existing value of the key-value pair.
Note:
If the specified key isn't found in the shared storage, the append() operation is equivalent to set(), that is, a new key-value pair with the specified key is added to the shared storage.
Return value
A Promise that fulfills with undefined.
Exceptions
- The
Promiserejects with aTypeErrorif:- The appended entry was not successfully stored in the database due to shared storage not being available (for example it is disabled using a browser setting).
keyand/orvalueexceed the browser-defined maximum length.- The calling site does not have the Shared Storage API included in a successful privacy sandbox enrollment process.
- In the case of
WorkletSharedStorage, thePromiserejects with aTypeErrorif the worklet module has not been added withSharedStorageWorklet.addModule().
Note:
In the case of WindowSharedStorage, if the append() operation doesn't successfully write to the database for a reason other than shared storage not being available, no error is thrown — the operation still fulfills with undefined.
Examples
window.sharedStorage
.append("integer-list", ",9")
.then(() => console.log("Value appended to integer list"));