Storage Service

Storage Service is a wrapper on top of the Web Storage API that provides additional features such as key prefixing and TTL.

Creating an instance

By default, Storage Service works with localStorage and using empathy as prefix. If that sounds good, you can just do:

const storage = new BrowserStorageService();

You can also customize the storage or prefix to be used in the constructor:

StorageService(storage?, prefix?)

For instance, if you want to use sessionStorage and test as prefix instead:

const storage = StorageService(sessionStorage, 'test');

Usage

Storage Service provides four public functions: setItem, getItem, removeItem and clear.

Setting an item

storage.setItem('x', { a: 'this', b: 'can', c: 'be', d: 'anything' });

With the default configuration, this will set an item in localStorage with the key empathy and no TTL.

Getting an item

const item = storage.getItem('x'); // Returns the item

Removing an item

const item = storage.removeItem('x'); // Also returns the item!

Cleaning all items

const removedItemCount = storage.clear(); // Returns the number of items that have been removed

Setting and item with TTL

The setItem function provides an optional third parameter to specify a time-to-live in milliseconds:

storage.setItem('x', 'value', 50);

After the specified time, the item won't be available via getItem or removeItem. Expired items are automatically removed from storage to avoid consuming space unnecessarily.