RxJava 3 support (#1047)

Author: Jawnnypoo

CHANGELOG.md

@@ -4,6 +4,7 @@
 > __BREAKING CHANGES__
 >
 > - FIX: Corrected the `Installation` property `appVersion` to be the build version instead of the version name. This aligns the property with its equivalent in the Parse iOS SDK. See [#902](https://github.com/parse-community/Parse-SDK-Android/issues/902) for details. Thanks to [Manuel Trezza](https://github.com/mtrezza).
+- Added RxJava module to transform `Task`s into RxJava types.
 
 ### 1.24.2
 - FIX: Fixed naming collission bug due to integration of bolts-tasks module. See [#1028](https://github.com/parse-community/Parse-SDK-Android/issues/1028) for details. Thanks to [Manuel Trezza](https://github.com/mtrezza)

README.md

@@ -40,6 +40,10 @@ dependencies {
     implementation "com.github.parse-community.Parse-SDK-Android:fcm:$parseVersion"
     // for Kotlin extensions support (optional)
     implementation "com.github.parse-community.Parse-SDK-Android:ktx:$parseVersion"
+    // for Kotlin coroutines support (optional)
+    implementation "com.github.parse-community.Parse-SDK-Android:coroutines:$parseVersion"
+    // for RxJava support (optional)
+    implementation "com.github.parse-community.Parse-SDK-Android:rxjava:$parseVersion"
 }
 ```
 
@@ -95,6 +99,7 @@ These are other official libraries we made that can help you create your Parse a
 - [Parse FCM](/fcm) - [Firebase Cloud Messaging](https://firebase.google.com/docs/cloud-messaging) support for sending push notifications.
 - [Parse KTX](/ktx) - Kotlin extensions for ease of developer use.
 - [Parse Coroutines](/coroutines) - Kotlin Coroutines support for various Parse async operations
+- [Parse RxJava](/rxjava) - Transform Parse `Task`s to RxJava `Completable`s and `Single`s
 - [ParseLiveQuery](https://github.com/parse-community/ParseLiveQuery-Android) - Realtime query subscription.
 - [ParseUI](https://github.com/parse-community/ParseUI-Android) - Prebuilt UI elements.
 

rxjava/.gitignore

@@ -0,0 +1 @@
+/build

rxjava/README.md

@@ -0,0 +1,57 @@
+# Parse SDK Android RxJava
+RxJava 3 support for Parse Android
+
+## Dependency
+
+After including JitPack:
+```gradle
+dependencies {
+    implementation "com.github.parse-community.Parse-SDK-Android:rxjava:latest.version.here"
+}
+```
+
+## Usage
+RxJava support is provided as an extension method on any `Task`. For example:
+```kotlin
+ParseTwitterUtils.logInInBackground(this)
+    .toSingle()
+    .subscribeOn(Schedulers.io())
+    .observeOn(AndroidSchedulers.mainThread())
+    .subscribe({
+        Timber.d("Logged in with user ${it.objectId}"
+    }, {
+        Timber.e(it)
+    })
+```
+Tasks with a Void results, ie. `Task<Void>` can be made into a `Completable`.
+For example:
+```kotlin
+val user = ParseUser.getCurrentUser()
+user.put("lastLoggedIn", System.currentTimeMillis())
+user.saveInBackground().toCompletable()
+    .subscribeOn(Schedulers.io())
+    .observeOn(AndroidSchedulers.mainThread())
+    .subscribe({
+        // yay
+        Timber.d("user saved")
+    }, {
+        Timber.e(it)
+    })
+```
+Note that these examples uses RxAndroid as well, which you need to add yourself as a dependency.
+
+### From Java
+If you need to call this from Java:
+```java
+ParseUser user = ParseUser.getCurrentUser();
+Completable completable = ParseRxJavaUtils.toCompletable(user.saveInBackground());
+```
+You would use similar calls to create a `Single<T>`.
+
+## License
+    Copyright (c) 2015-present, Parse, LLC.
+    All rights reserved.
+
+    This source code is licensed under the BSD-style license found in the
+    LICENSE file in the root directory of this source tree. An additional grant
+    of patent rights can be found in the PATENTS file in the same directory.

rxjava/build.gradle

@@ -0,0 +1,37 @@
+apply plugin: "com.android.library"
+apply plugin: "kotlin-android"
+
+android {
+    compileSdkVersion rootProject.ext.compileSdkVersion
+
+    defaultConfig {
+        minSdkVersion rootProject.ext.minSdkVersion
+        targetSdkVersion rootProject.ext.targetSdkVersion
+        versionCode 1
+        versionName "1.0"
+    }
+
+    packagingOptions {
+        exclude "**/BuildConfig.class"
+    }
+
+    lintOptions {
+        abortOnError false
+    }
+
+    buildTypes {
+        release {
+            minifyEnabled false
+            proguardFiles getDefaultProguardFile("proguard-android.txt"), "proguard-rules.pro"
+        }
+    }
+
+}
+
+dependencies {
+    api "org.jetbrains.kotlin:kotlin-stdlib-jdk7:$kotlin_version"
+    api "io.reactivex.rxjava3:rxjava:3.0.4"
+    implementation project(":parse")
+}
+
+apply from: "https://raw.githubusercontent.com/Commit451/gradle-android-javadocs/1.1.0/gradle-android-javadocs.gradle"

rxjava/proguard-rules.pro

@@ -0,0 +1 @@
+<manifest package="com.parse.rxjava" />

rxjava/src/main/AndroidManifest.xml

@@ -0,0 +1,28 @@
+@file:JvmName("ParseRxJavaUtils")
+@file:Suppress("unused")
+
+package com.parse.rxjava
+
+import com.parse.boltsinternal.Task
+import io.reactivex.rxjava3.core.Completable
+import io.reactivex.rxjava3.core.Single
+
+fun <T> Task<T>.toSingle(): Single<T> {
+    return Single.defer {
+        this.waitForCompletion()
+        if (isFaulted) {
+            throw error
+        }
+        Single.just(result)
+    }
+}
+
+fun Task<Void>.toCompletable(): Completable {
+    return Completable.defer {
+        this.waitForCompletion()
+        if (isFaulted) {
+            throw error
+        }
+        Completable.complete()
+    }
+}

rxjava/src/main/java/com/parse/rxjava/Extensions.kt

@@ -1,2 +1,2 @@
-include ':parse', ':fcm', ':gcm', ':ktx', ':coroutines', ':google', ':facebook', ':twitter', ':bolts-tasks'
+include ':parse', ':fcm', ':gcm', ':ktx', ':coroutines', 'rxjava', ':google', ':facebook', ':twitter', ':bolts-tasks'