Upgrading to AngularFire 5.0
AngularFire 5.0 is a refactor of the AngularFireDatabase
module. It removes the FirebaseListObservable
and FirebaseObjectObservable
in favor of a generic based service API.
Updating FirebaseListObservable
to AngularFireList<T>
Rather than .list()
returning a FirebaseListObservable
, it now returns an AngularFireList<T>
. This service contains methods that allow you to manipulate and stream data.
In the case of streaming back data, you now call one of the observable methods on AngularFireList
.
4.0
constructor(afDb: AngularFireDatabase) {
afDb.list('items').subscribe(console.log);
}
5.0
constructor(afDb: AngularFireDatabase) {
afDb.list<Item>('items').valueChanges().subscribe(console.log);
}
The same concepts apply to FirebaseObjectObservable
to AngularFireObject
.
Moving away from $key
and $value
In AngularFireDatabase 4.0 the snapshot was automatically unwrapped for you and metadata was placed in $
property. The Firebase Database rejects any keys with $
in them so this mechanism allowed us to provide you with important metadata alongside your actual data. However, persisting the object could be a pain in some cases as the SDK would reject any $
based properties. In 5.0 we have moved away from $
properties and we provide multiple observable methods for receiving the data.
Calling .valueChanges()
returns an Observable without any metadata. If you are already persisting the key as a property then you are fine. However, if you are relying on $key
, then you need to use .snapshotChanges()
and transform the data with an observable .map()
.
4.0
constructor(afDb: AngularFireDatabase) {
afDb.list('items').subscribe(items => {
const allKeys = items.map(item => item.$key);
});
}
5.0
constructor(afDb: AngularFireDatabase) {
afDb.list('items').snapshotChanges().pipe(
map(actions =>
actions.map(a => ({ key: a.key, ...a.payload.val() }))
)
).subscribe(items => {
return items.map(item => item.key);
});
}
Data manipulation methods
AngularFire 5.0 removes all custom observables which means their custom operators are gone as well. Instead of using custom operators on either a FirebaseListObservable
or a FirebaseObjectObservable
, use the methods on the service based APIs: AngularFireList
and AngularFireObject
. There is no resulting code change, but it worth pointing out.
4.0
constructor(afDb: AngularFireDatabase) {
const listObservable = afDb.list('items');
listObservable.push({ name: 'item' });
listObservable.subscribe();
}
5.0
constructor(afDb: AngularFireDatabase) {
const afList = afDb.list('items');
afList.push({ name: 'item' });
const listObservable = afList.snapshotChanges();
listObservable.subscribe();
}