StorageArea.get()

Retrieves one or more items from the storage area.

This is an asynchronous function that returns a Promise.

Syntax

let results = browser.storage.<storageType>.get(
  keys    // null, string, object or array of strings
)

Where <storageType> is one of the storage types — sync, local, session, or managed.

Parameters

keys: A key (string) or keys (an array of strings, or an object specifying default values) to identify the item(s) to be retrieved from storage. If you pass an empty object or array here, an empty object will be retrieved. If you pass null, or an undefined value, the entire storage contents will be retrieved.

A Promise that resolves to a results object, containing a key-value pair for every key in keys found in the storage area. When keys is an object, any key that isn't found in storage takes the default value from the keys object.

If the operation fails, the promise is rejected with an error message.

If managed storage is not set, undefined is returned.

Warning: In Firefox, if an extension's managed storage has not been configured with a native manifest or using the 3rdparty enterprise policy, an exception is thrown when using this function to access managed storage (see Firefox bug 1868153). This issue can be avoided by catching the error. This issue is related to the lack of support for the storage.managed_schema manifest key (see Firefox bug 1771731).

Examples

Suppose storage contains two items:

// storage contains two items,
// "kitten" and "monster"
browser.storage.local.set({
  kitten: { name: "Mog", eats: "mice" },
  monster: { name: "Kraken", eats: "people" },
});

Define success and failure handlers for the promise:

function onGot(item) {
  console.log(item);
}

function onError(error) {
  console.log(`Error: ${error}`);
}

With no keys argument, retrieve everything:

let gettingItem = browser.storage.local.get();
gettingItem.then(onGot, onError);

// -> Object { kitten: Object, monster: Object }

With an empty keys argument, return nothing:

// with an empty array, retrieve nothing
let gettingItem = browser.storage.local.get([]);
gettingItem.then(onGot, onError);

// -> Object { }

With the name of an object, retrieve the match:

let gettingItem = browser.storage.local.get("kitten");
gettingItem.then(onGot, onError);

// -> Object { kitten: Object }

With an array of object names, retrieve all matches:

let gettingItem = browser.storage.local.get([
  "kitten",
  "monster",
  "grapefruit",
]);
gettingItem.then(onGot, onError);

// -> Object { kitten: Object, monster: Object }

With an object with object names as keys and the default value as value:

let gettingItem = browser.storage.local.get({
  kitten: "no kitten",
  monster: "no monster",
  grapefruit: {
    name: "Grape Fruit",
    eats: "Water",
  },
});

// -> Object { kitten: Object, monster: Object, grapefruit: Object }

Chrome examples

chrome.storage.local.get("kitten", (items) => {
  console.log(items.kitten); // -> {name:"Mog", eats:"mice"}
});

Or using a Promise

let gettingItem = new Promise((resolve) =>
  chrome.storage.local.get("kitten", resolve),
);
gettingItem.then(onGot); // -> Object { kitten: Object }

Browser compatibility

Note: This API is based on Chromium's chrome.storage API. This documentation is derived from storage.json in the Chromium code.