[docs] added migration guide for v1 -> v2

docs/_sidebar.md

@@ -3,6 +3,7 @@
  - [Installation - iOS](/installation-ios)
  - [Installation - Android](/installation-android)
  - [Usage](/usage)
+ - [Migration Guide](/migration-guide)
 
 - Contributing
  - [Guidelines](/contributing/guidelines)

docs/migration-guide.md

@@ -0,0 +1,147 @@
+# Migration
+
+## From v1 to v2
+
+The below is a quick summary of steps to take when migrating from v1 to v2 of RNFirebase. Please see the [v2 change log](https://github.com/invertase/react-native-firebase/releases/tag/v2.0.0) for detailed changes.
+
+##### 1) Install the latest version of RNFirebase:
+> `npm i react-native-firebase@latest --save`
+
+
+
+
+##### 2) Upgrade react-native version (only if you're currently lower than v0.40):
+
+> For example: `npm i react-native@0.44.0 react@16.0.0-alpha.6 --save`
+
+
+
+
+##### 3) Update your JS code to reflect deprecations/breaking changes:
+
+<detail>
+
+- [deprecated] providerId should now be used instead of provider whilst obtaining auth credentials. The latter will be removed in future releases.
+- [deprecated] Deprecated User.getToken in favour of User.getIdToken.
+- [breaking] User.reauthenticate has been removed in favour of User.reauthenticateWithCredential.
+- [breaking] User.link has been removed in favour of User.linkWithCredential.
+- [breaking] Removed unnecessary didReceiveNotificationResponse and willPresentNotification methods for iOS messaging. Added additional didReceiveRemoteNotification method.
+- [breaking] firebase.messaging().onTokenRefresh and firebase.messaging().onMessage return a function to unsubscribe as per the Web SDK spec: https://firebase.google.com/docs/reference/js/firebase.messaging.Messaging#onMessage. Previously they returned an object with a .remove() method.
+
+</detail>
+
+
+
+
+##### 4) Android - Update `app/build.gradle`:
+
+<detail>
+All firebase modules are now optional so you only need to import the Firebase functionality that you require in your application.
+
+You need to make a couple of changes to your `app/build.gradle` file.  Update the react-native-firebase compile statement to read:
+
+```gradle
+compile(project(':react-native-firebase')) {
+  transitive = false
+}
+compile "com.google.firebase:firebase-core:11.0.0"
+```
+Add each of the firebase modules you need from the following list:
+```gradle
+compile "com.google.firebase:firebase-ads:11.0.0"
+compile "com.google.firebase:firebase-analytics:11.0.0"
+compile "com.google.firebase:firebase-auth:11.0.0"
+compile "com.google.firebase:firebase-config:11.0.0"
+compile "com.google.firebase:firebase-crash:11.0.0"
+compile "com.google.firebase:firebase-database:11.0.0"
+compile "com.google.firebase:firebase-messaging:11.0.0"
+compile "com.google.firebase:firebase-perf:11.0.0"
+compile "com.google.firebase:firebase-storage:11.0.0"
+```
+
+</detail>
+
+
+
+##### 5) Android - Update `MainApplication.java`:
+
+<detail>
+
+Update `MainApplication.java` and import the modules you require / currently use:
+
+```java
+import io.invertase.firebase.admob.RNFirebaseAdMobPackage; //Firebase AdMob
+import io.invertase.firebase.analytics.RNFirebaseAnalyticsPackage; // Firebase Analytics
+import io.invertase.firebase.auth.RNFirebaseAuthPackage; // Firebase Auth
+import io.invertase.firebase.config.RNFirebaseRemoteConfigPackage; // Firebase Remote Config
+import io.invertase.firebase.crash.RNFirebaseCrashPackage; // Firebase Crash Reporting
+import io.invertase.firebase.database.RNFirebaseDatabasePackage; // Firebase Realtime Database
+import io.invertase.firebase.messaging.RNFirebaseMessagingPackage; // Firebase Cloud Messaging
+import io.invertase.firebase.perf.RNFirebasePerformancePackage; // Firebase Performance Monitoring
+import io.invertase.firebase.storage.RNFirebaseStoragePackage; // Firebase Storage
+```
+Add the packages to the `getPackages()` method as required:
+```java
+@Override
+    protected List<ReactPackage> getPackages() {
+      return Arrays.<ReactPackage>asList(
+          new MainReactPackage(),
+          new RNFirebasePackage(),  // <-- Add this line - it's the only one that's required
+
+          // add these optional packages as appropriate
+          new RNFirebaseAdMobPackage(),
+          new RNFirebaseAnalyticsPackage(),
+          new RNFirebaseAuthPackage(),
+          new RNFirebaseRemoteConfigPackage(),
+          new RNFirebaseCrashPackage(),
+          new RNFirebaseDatabasePackage(),
+          new RNFirebaseMessagingPackage(),
+          new RNFirebasePerformancePackage(),
+          new RNFirebaseStoragePackage()
+      );
+    }
+```
+
+</detail>
+
+
+
+##### 6) iOS - Update podfile:
+
+<detail>
+
+As all firebase modules are now optional you only need to import the Firebase functionality that you require in your application.  Simply update your Podfile to only include the Firebase modules for functionality that you require in your app.
+
+For example if you only use Auth and Storage in your app then your podfile would look like the below:
+
+```ruby
+install! 'cocoapods', :deterministic_uuids => false
+# Uncomment this line to define a global platform for your project
+# platform :ios, '9.0'
+
+target 'ReactNativeFirebaseDemo' do
+  platform :ios, '8.0'
+  # Uncomment this line if you're using Swift or would like to use dynamic frameworks
+  # use_frameworks!
+
+  react_native_path = "../node_modules/react-native"
+  pod "Yoga", :path => "#{react_native_path}/ReactCommon/yoga"
+  pod 'React', :path => '#{react_native_path}', :subspecs => [
+    'BatchedBridge', # Required For React Native 0.45.0+
+    'Core',
+    # Add any other subspecs you want to use in your project
+    # ...
+  ]
+
+  # Core is always required
+  pod 'Firebase/Core'
+
+  # Optional modules
+  pod 'Firebase/Auth'
+  pod 'Firebase/Storage'
+
+  pod 'RNFirebase', :path => '../node_modules/react-native-firebase'
+end
+```
+
+</detail>