ngStorage
An AngularJS module that makes Web Storage working in the Angular Way. Contains two services: $localStorage and $sessionStorage.
Differences with Other Implementations
-
No Getter 'n' Setter Bullshit - Right from AngularJS homepage: "Unlike other frameworks, there is no need to [...] wrap the model in accessors methods. Just plain old JavaScript here." Now you can enjoy the same benefit while achieving data persistence with Web Storage.
-
sessionStorage - We got this often-overlooked buddy covered.
-
Cleanly-Authored Code - Written in the Angular Way, well-structured with testability in mind.
-
No Cookie Fallback - With Web Storage being readily available in all the browsers AngularJS officially supports, such fallback is largely redundant.
Install
Bower
bower install ngstorage
NOTE: We are ngstorage and NOT ngStorage. The casing is important!
NPM
npm install ngstorage
NOTE: We are ngstorage and NOT ngStorage. The casing is important!
nuget
Install-Package gsklee.ngStorage
Or search for Angular ngStorage in the nuget package manager. https://www.nuget.org/packages/gsklee.ngStorage
CDN
cdnjs
cdnjs now hosts ngStorage at https://cdnjs.com/libraries/ngStorage
To use it
<script src="https://cdnjs.cloudflare.com/ajax/libs/ngStorage/0.3.10/ngStorage.min.js"></script>
jsDelivr
jsDelivr hosts ngStorage at http://www.jsdelivr.com/#!ngstorage
To use is
<script src="https://cdn.jsdelivr.net/npm/ngstorage@0.3.11/ngStorage.min.js"></script>
Usage
Require ngStorage and Inject the Services
angular.module('app', [
'ngStorage'
]).controller('Ctrl', function(
$scope,
$localStorage,
$sessionStorage
){});
Read and Write, Demo
Pass $localStorage (or $sessionStorage) by reference to a hook under $scope in plain ol' JavaScript:
$scope.$storage = $localStorage;
And use it like you-already-know:
<body ng-controller="Ctrl">
<button ng-click="$storage.counter = $storage.counter + 1">{{$storage.counter}}</button>
</body>
Optionally, specify default values using the
$default()method:$scope.$storage = $localStorage.$default({ counter: 42 });
With this setup, changes will be automatically sync'd between $scope.$storage, $localStorage, and localStorage - even across different browser tabs!
Read and Write Alternative (Not Recommended), Demo
If you're not fond of the presence of $scope.$storage, you can always use watchers:
$scope.counter = $localStorage.counter, 42;
$scope.$watch('counter', function() {
$localStorage.counter = $scope.counter;
});
$scope.$watch(function() {
return angular.toJson($localStorage);
}, function() {
$scope.counter = $localStorage.counter;
});
This, however, is not the way ngStorage is designed to be used with. As can be easily seen by comparing the demos, this approach is way more verbose, and may have potential performance implications as the values being watched quickly grow.
Delete, Demo
Plain ol' JavaScript again, what else could you better expect?
// Both will do
delete $scope.$storage.counter;
delete $localStorage.counter;
This will delete the corresponding entry inside the Web Storage.
Delete Everything, Demo
If you wish to clear the Storage in one go, use the $reset() method:
$localStorage.$reset();
Optionally, pass in an object you'd like the Storage to reset to:
$localStorage.$reset({ counter: 42 });
Permitted Values, Demo
You can store anything except those not supported by JSON:
Infinity,NaN- Will be replaced withnull.undefined, Function - Will be removed.
Usage from config phase
To read and set values during the Angular config phase use the .get/.set
functions provided by the provider.
var app = angular.module('app', ['ngStorage'])
.config(['$localStorageProvider',
function ($localStorageProvider) {
$localStorageProvider.get('MyKey');
$localStorageProvider.set('MyKey', { k: 'value' });
}]);
Prefix
To change the prefix used by ngStorage use the provider function setKeyPrefix
during the config phase.
var app = angular.module('app', ['ngStorage'])
.config(['$localStorageProvider',
function ($localStorageProvider) {
$localStorageProvider.setKeyPrefix('NewPrefix');
}])
Custom serialization
To change how ngStorage serializes and deserializes values (uses JSON by default) you can use your own functions.
angular.module('app', ['ngStorage'])
.config(['$localStorageProvider',
function ($localStorageProvider) {
var mySerializer = function (value) {
// Do what you want with the value.
return value;
};
var myDeserializer = function (value) {
return value;
};
$localStorageProvider.setSerializer(mySerializer);
$localStorageProvider.setDeserializer(myDeserializer);
}];)
Minification
Just run $ npm install to install dependencies. Then run $ grunt for minification.
Hints
Watch the watch
ngStorage internally uses an Angular watch to monitor changes to the $storage/$localStorage objects. That means that a digest cycle is required to persist your new values into the browser local storage.
Normally this is not a problem, but, for example, if you launch a new window after saving a value...
$scope.$storage.school = theSchool;
$log.debug("launching " + url);
var myWindow = $window.open("", "_self");
myWindow.document.write(response.data);
the new values will not reliably be saved into the browser local storage. Allow a digest cycle to occur by using a zero-value $timeout as:
$scope.$storage.school = theSchool;
$log.debug("launching and saving the new value" + url);
$timeout(function(){
var myWindow = $window.open("", "_self");
myWindow.document.write(response.data);
});
or better using $scope.$evalAsync as:
$scope.$storage.school = theSchool;
$log.debug("launching and saving the new value" + url);
$scope.$evalAsync(function(){
var myWindow = $window.open("", "_self");
myWindow.document.write(response.data);
});
And your new values will be persisted correctly.
Todos
- ngdoc Documentation
- Namespace Support
- Unit Tests
- Grunt Tasks
Any contribution will be appreciated.