Android RxFirebase

Simple and lightweight RxJava2 wrapper for use with the Android Firebase client

The Tasks API

Starting with Google Play services version 9.0.0, you can use a Task API and a number of methods that return Task or its subclasses. Task is an API that represents asynchronous method calls, similar to PendingResult in previous versions of Google Play Services.

Usage

Many of the operations can be referenced in further detail in the official documentation.

Much of this library is built around the latest changes from the RxTasks library since many of the core functions return a Task<T> result which can easily be converted to an RxJava2 type.

As such, much of the core behaviour using in previous versions of this library have been deprecated. With behaviour remaining to consume child events, and convert value events into RxJava2 types.

A common method that returns a Task is FirebaseAuth.signInAnonymously(). It returns a Task<AuthResult> which means the task will return an AuthResult object when it succeeds.

For example the Firebase sign in API asynchronously returns an AuthResult which can be consumed via toSingle method as an extension of Task<T>.

If consuming from Java code, the class RxFirebaseAuth can be used with JVM static behaviour to honour previous API contracts, however these are marked as deprecated. Extension functions of provided types should be preferred.

FirebaseAuth
  .getInstance()
  .onAuthState()
  .subscribe { /* ... */ }

FirebaseDatabase
  .getInstance()
  .getReference("server/saving-data/fireblog/posts")
  .onChildAdded<String>()
  .subscribe { /* ... */ }

Installation

dependencies {
  compile 'io.ashdavies.rx:rx-firebase:+'
}

Description

A lightweight RxJava2 wrapper for the Android Firebase client SDK, the user is expected to own the lifecycle of an asynchronous request via RxJava2 Disposable handling, however elements in this library will properly unregister listeners when a Publisher is cancelled, except in the case of value setting where it is only possible to register a listener when making the request. In this case the emitter is checked for it's subscription state.

Whilst the FirebaseDatabase api is mirrored with RxFirebaseDatabase it only really uses the database reference, this is so that the reference hierarchy can easily be traversed through child and parent elements. Methods requiring FirebaseDatabase obtain this from the DatabaseReference and allow you to chain further requests by returning itself.

Future development

Further development for this library has not been planned, and will soon become deprecated, it is recommended to use Kotlin Coroutines integration with Google Play Services Tasks API.