Storage

Storage is a functional wrapper around localForage. That means it's an asynchronous browser storage with multiple back-ends (IndexedDB, WebSQL, localStorage), which is built for a better offline experience.

The main differences with localForage:

• batch support
• error first node-style callbacks, fixes #55
• simple API inspired by yields/store
• optional callbacks, return promises
• development mode

Installation

$ bower install storage
$ component install ask11/storage
$ npm install ask11-storage --save

Standalone build available as storage.js.

<script src="storage.js"></script>
<script>window.storage('key', fn);</script>

Example

// set
storage.set('foo', 'val', fn);
storage.set({ foo: 'val', bar: 'baz' }, fn);

// get
storage.get('foo', fn); // 'val'
storage.get(['foo', 'bar'], fn); // ['val', 'baz']

// delete
storage.del('foo', fn)
storage.del(['foo', 'bar', 'baz'], fn);

API

Each method returns promise, and accepts optional callback.

storage([key, val, fn])

Main function is facade to get/set/del/count methods. It's inspired by yields/store. Setting a key to null is equivalent to deleting the key via storage.del(key).

// set
storage({ key: 'val', key2: 'val2'}, function(err) {});

// get
storage('key', function(err, val) {});
storage(['key', 'key2'], function(err, all) {}); // all.length == 2

// count
storage(function(err, count) {}); // count == 2

// delete
storage('key', null, function(err) {});
storage(['key', 'key2'], null, function(err) {});

storage.get(key, [fn])

Get key value.

storage.get([key1, key2, ..., keyn], [fn])

Get group of values. Callbacks return array of values for each key. If key does not exist, it returns null on this position.

storage.set(key, val, [fn])

Set key to val. You can store any kind of data, including blobs.

storage.del(key, [fn])

Delete key.

storage.set({ key1: val1, key2: val2, key3: val3 }, [fn])

Run a batch operation. Simple way to create, update, remove multiple records. Use null to remove record.

// assume we have 2 records
storage('foo', 7, fn)
storage('bar', ['one', 'two', 'three'], fn);

storage({
  baz: 'val' // create new val
  foo: 1000, // update `foo` value
  bar: null, // remove `bar`
}, function(err) {});

storage.del([key1, key2, ..., keyn], [fn])

Delete a group of keys in one request.

storage.clear()

Clear storage.

storage.count()

Count records.

storage.development

Work with async storage in developer console can be unpleasant. Setup development flag and storage will console.log() results of get or count.

storage.development = true;
storage.set({ foo: 1, bar: 2 });
storage.get(['foo', 'bar']);
// => [1 ,2]
storage.del('bar');
storage.count();
// => 1
// shortcut to: storage.count().then(console.log.bind(console));

storage.forage

It gives you access to the localForage instance. You can use it to configure backend. By default storage setups only name option as storage.

storage.forage.config({ name: 'my-name' });
if (!window.indexedDB) storage.forage.setDriver('localStorageWrapper');

License

Aleksey Kulikov, MIT.