Firebase bindings for Ember.js
ember-firebase is a stable, thoroughly-tested set of Firebase bindings for Ember.js.
Firebase.Binding
is a subclass of Ember.Binding
that allows you to bind directly to a Firebase location reference from an arbitrary object path. The binding can be either two-way or read-only. Use it anywhere you would normally use an Ember.Binding
.
var ref = new Firebase('https://my-firebase.firebaseio.com');
var connectedRef = ref.child('.info/connected');
var CurrentUserController = Ember.ObjectController.extend({
// Tells whether or not the current user is connected to
// the Firebase servers. Useful for managing presence.
isConnected: false,
// This binding keeps the isConnected property in sync
// with the value at the .info/connected ref.
isConnectedBinding: Firebase.Binding.oneWay(connectedRef)
});
Note: The Firebase.Binding
API closely follows Ember.Binding
, so things like Firebase.Binding#connect
, Firebase.Binding#disconnect
, Firebase.bind
and Firebase.oneWay
all work as you would expect.
Firebase.Hash
is an Ember.ObjectProxy
subclass that can be used to model data at a single Firebase location reference, including children. Use it anywhere you would normally use an Ember.Object
(e.g. as the content
of an Ember.ObjectController
).
You only need to give it a ref
property that points to the Firebase location you want to sync with. When you set properties on the object they automatically sync to Firebase. When children of that location are updated in Firebase, they sync to your object.
var ref = new Firebase('https://my-firebase.firebaseio.com');
var User = Firebase.Hash.extend({
fullName: function () {
return this.get('firstName') + ' ' + this.get('lastName');
}.property('firstName', 'lastName')
});
var user = User.create({
// The ref property points to the location where you want
// to store the data for this object.
ref: ref.child('users/mj'),
// These properties will be set immediately and will sync
// to the Firebase servers.
firstName: 'Michael',
lastName: 'Jackson'
});
user.get('fullName'); // => "Michael Jackson"
user.set('lastName', 'Johnson');
user.get('fullName'); // => "Michael Johnson"
Firebase.List
is an Ember.ArrayProxy
subclass that lets you store array-like data at a Firebase location. Use it anywhere you would normally use an Ember.Array
(e.g. as the content
of an Ember.ArrayController
).
When you create a new Firebase.List
, you need to give it a ref
property that it will use to sync with Firebase. Note: You can also use a query here, e.g. to limit the number of items in the list.
var ref = new Firebase('https://my-firebase.firebaseio.com');
var Messages = Firebase.List.extend();
var messages = Messages.create({
// The ref property points to the location where you want
// to store the data for this object.
ref: ref.child('messages')
});
messages.pushObject({ text: 'Hello world!' });
messages.get('length'); // => 1
Firebase.Hash
and Firebase.List
both create values using their createValueFromSnapshot
method. This method is responsible for creating a JavaScript value to store in your object based on the DataSnapshot object received from Firebase.
The default implementation of this method simply returns snapshot.val()
, but you can override it to do something more interesting. For example, you may be storing a list of ids that you'd like to convert to live proxy objects as ids are added to or removed from the list. Or you may want to model the nested data at a given location with a tree of proxy objects.
For example, the following Firebase.Hash
subclass will recursively create a new instance of itself for every node in the tree.
var NestedHash = Firebase.Hash.extend({
createValueFromSnapshot: function (snapshot) {
// If the snapshot has children, make another NestedHash to
// represent the data at this location.
if (snapshot.hasChildren()) {
return NestedHash.create({ ref: snapshot.ref() });
}
return this._super(snapshot);
}
});
Firebase.child
makes it easy to create a new child reference from an existing reference. If no child name is given, a new one is automatically generated. Otherwise, the child name may be a plain string or a string format that is interpolated with the remaining arguments to the function. If any interpolated argument has an id
property, it is automatically used.
Firebase.child(ref); // same as ref.push()
Firebase.child(ref, 'myName'); // same as ref.child('myName')
Firebase.child(ref, 'chats/%@', chat.id); // same as ref.child('chats/' + chat.id);
Firebase.child(ref, 'chats/%@', chat); // same as ref.child('chats/' + chat.id);
In addition to Firebase.Binding
, Firebase.Hash
, and Firebase.List
, ember-firebase includes a suite of query methods that are useful for doing one-off queries. Each of these utility methods returns a promise that resolves when the sync with the Firebase servers is complete.
Firebase.get(ref).then(function (value) {
// value is the value stored at the given ref
});
Firebase.getWithDefault(ref, defaultValue).then(function (value) {
// value is the value stored at the given ref, or the
// defaultValue if it was null
});
Firebase.set(ref, value).then(function () {
// the set is sync'd to Firebase
});
Firebase.push(ref, value).then(function (newRef) {
// the newRef is sync'd to Firebase
});
Firebase.remove(ref).then(function () {
// the ref was removed from Firebase
});
Firebase.update(ref, { some: 'updates' }).then(function () {
// the ref was updated with the given properties
});
To run the tests, change the BASE_REF
variable in spec/index.html
to point to any Firebase location you have read/write access to and open the file in a browser.