README.md

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## NOTES:
[react-native-firebase](https://github.com/invertase/react-native-firebase/releases/tag/v4.0.0) has introduced new firebase messaging and remote/local notification features. It has good integration with other firebase features.  I would recommend new comers to check that.

Note that there are some advanced features still in progress 
- handle iOS remote notification when app is not running
- custom iOS notification actions 

### To existing react-native-fcm users
`react-native-firebase` now can do what `react-native-fcm` can so it is a waste of effort to build the same thing in parallel. 

Since I'm getting busier these days and start feeling challenging to maintain this repo every day while `react-native-firebase` has a larger team/company backing it, existing users may consider migrating to `react-native-firebase`.

I've created [an example project](https://github.com/evollu/react-native-fcm/tree/firebase/Examples/firebase-migration) using react-native-firebase as a migration reference

`react-native-fcm` will still take PRs and bug fixes, but possibly no new feature developement any more.



### Versions
- after v16.0.0, Android target SDK has be to >= 26 and build tool has to be >= 26.0.x
- for iOS SDK < 4, use react-native-fcm@6.2.3 (v6.x is still compatible with Firebase SDK v4)
- for RN < 0.40.0, use react-native-fcm@2.5.6
- for RN < 0.33.0, use react-native-fcm@1.1.0
- for RN < 0.30.0, use react-native-fcm@1.0.15

### Example
- An example working project is available at: https://github.com/evollu/react-native-fcm/tree/master/Examples/simple-fcm-client

## Installation

- Run `npm install react-native-fcm --save`
- [Link libraries](https://facebook.github.io/react-native/docs/linking-libraries-ios.html)
  Note: the auto link doesn't work with xcworkspace so CocoaPods user needs to do manual linking
- You many need [this package for huawei phone](https://github.com/pgengoux/react-native-huawei-protected-apps)

## Configure Firebase Console
### FCM config file

In [firebase console](https://console.firebase.google.com/), you can:
- for **Android**: download `google-services.json` file and place it in `android/app` directory.
- for **iOS**: download `GoogleService-Info.plist` file and place it in `/ios/your-project-name` directory (next to your `Info.plist`)

Make sure you have certificates setup by following
https://firebase.google.com/docs/cloud-messaging/ios/certs

---

## Android Configuration

- As `react-native link` sometimes has glitches, make sure you have this line added

### Edit `android/build.gradle`:

**NOTE:** The followed line may not be up-to-dated. Please refer to https://firebase.google.com/docs/android/setup

```
buildscript {
    repositories {
        // ...
        google() // Google's Maven repository
    }
    // ...
    dependencies {
        // ...
        classpath 'com.google.gms:google-services:4.0.2' // google-services plugin
    }
}

allprojects {
    // ...
    repositories {
        // ...
        google() // Google's Maven repository
    }
}
```

### Edit `android/app/build.gradle`:

**NOTE:** Please refer to https://firebase.google.com/docs/android/setup

```
dependencies {
    // ...
    compile project(':react-native-fcm')

    // ...
    
    // Automatically selecting the latest available version
    implementation 'com.google.firebase:firebase-core'
    implementation 'com.google.firebase:firebase-messaging'
}

// ADD THIS AT THE BOTTOM
apply plugin: 'com.google.gms.google-services'
```

### Edit `android/app/src/main/AndroidManifest.xml`:

**NOTE:** The resource `@mipmap/ic_notif` is referring to `android/app/src/res/mipmap-<resolution>/` folder. Feel free to change the filename if you have a customised icon for notification.

```diff
  <application
    ...
    android:theme="@style/AppTheme">

+    <meta-data android:name="com.google.firebase.messaging.default_notification_icon" android:resource="@mipmap/ic_notif"/>
+    <meta-data android:name="com.google.firebase.messaging.default_notification_channel_id" android:value="my_default_channel"/>

+   <service android:name="com.evollu.react.fcm.MessagingService" android:enabled="true" android:exported="true">
+     <intent-filter>
+       <action android:name="com.google.firebase.MESSAGING_EVENT"/>
+     </intent-filter>
+   </service>

+   <service android:name="com.evollu.react.fcm.InstanceIdService" android:exported="false">
+     <intent-filter>
+       <action android:name="com.google.firebase.INSTANCE_ID_EVENT"/>
+     </intent-filter>
+   </service>

    ...
```

### Edit `android/app/build.gradle`:

**NOTE:** after v16.0.0, Android target SDK has be to >= 26 and build tool has to be >= 26.0.x

**NOTE:** Make sure the version matches this library.

```diff
+ compileSdkVersion 27
+    buildToolsVersion "27.0.3"

    defaultConfig {
        applicationId "com.google.firebase.quickstart.fcm"
        minSdkVersion 16
+        targetSdkVersion 27
        versionCode 1
        versionName "1.0"
        ndk {
            abiFilters "armeabi-v7a", "x86"
        }
    }

 dependencies {
+    compile project(':react-native-fcm')
     compile fileTree(dir: "libs", include: ["*.jar"])
     compile "com.facebook.react:react-native:+"  // From node_modules
 }
 
 //bottom
 + apply plugin: "com.google.gms.google-services"
```
If you are using other firebase libraries, check this for solving dependency conflicts https://github.com/evollu/react-native-fcm/blob/master/Examples/simple-fcm-client/android/app/build.gradle#L133

### Edit `android/settings.gradle`
```diff
  ...
+ include ':react-native-fcm'
+ project(':react-native-fcm').projectDir = new File(rootProject.projectDir, '../node_modules/react-native-fcm/android')
  include ':app'
```

- Edit `MainActivity.java`. This fixes [a bug](https://stackoverflow.com/questions/14853327/intent-not-restored-correctly-after-activity-is-killed-if-clear-top-and-single-t/18307360#18307360)
```diff
+ import android.content.Intent;
...
public class MainActivity extends ReactActivity {
+ @Override
+    public void onNewIntent(Intent intent) {
+        super.onNewIntent(intent);
+        setIntent(intent);
+    }
}
```

### Make sure in `MainApplication.java` you have the code below:

**NOTE:** The packages listed inside should appear once only. `react-native link` sometimes can mess up this part, please remove duplicated packeges.

```diff
    @Override
    protected List<ReactPackage> getPackages() {
      return Arrays.<ReactPackage>asList(
          new MainReactPackage(),
            new MapsPackage(),
+           new FIRMessagingPackage()
      );
    }

+ @Override
+  public void onCreate() { // <-- Check this block exists
+    super.onCreate();
+    SoLoader.init(this, /* native exopackage */ false); // <-- Check this line exists within the block
+  }
```

### Config for notification and `click_action` in Android

To allow android to respond to `click_action`, you need to define Activities and filter on specific intent. Since all javascript is running in MainActivity, you can have MainActivity to handle actions:

Edit `AndroidManifest.xml`:

```diff
  <activity
    android:name=".MainActivity"
    android:label="@string/app_name"
    android:windowSoftInputMode="adjustResize"
+   android:launchMode="singleTop"
    android:configChanges="keyboard|keyboardHidden|orientation|screenSize">
    <intent-filter>
      <action android:name="android.intent.action.MAIN" />
      <category android:name="android.intent.category.LAUNCHER" />
    </intent-filter>
  </activity>
```

Notes:
- `launchMode="singleTop"` is to reuse MainActivity, you can use `singleTask` or `singleInstance` as well depend on your need. [this link explains the behavior well](https://blog.mindorks.com/android-activity-launchmode-explained-cbc6cf996802)
- you if want to handle `click_action` you need to add custom intent-filter, check native android documentation


If you are using RN < 0.30.0 and react-native-fcm < 1.0.16, pass intent into package, edit `MainActivity.java`:

- RN 0.28:

```diff
  import com.facebook.react.ReactActivity;
+ import android.content.Intent;

  public class MainActivity extends ReactActivity {

+   @Override
+   public void onNewIntent (Intent intent) {
+     super.onNewIntent(intent);
+       setIntent(intent);
+   }       
```

NOTE: Verify that react-native links correctly in `MainApplication.java`

```diff
import android.app.application
...
+import com.evollu.react.fcm.FIRMessagingPackage;
```
....
```diff
    @Override
    protected List<ReactPackage> getPackages() {
      return Arrays.<ReactPackage>asList(
          new MainReactPackage(),
          new VectorIconsPackage(),
+         new FIRMessagingPackage(),
          new RNDeviceInfo(),
      );
    }
 ```   



- RN <= 0.27:

```diff
  import com.facebook.react.ReactActivity;
+ import android.content.Intent;

  public class MainActivity extends ReactActivity {

+   @Override
+   protected void onNewIntent (Intent intent) {
+     super.onNewIntent(intent);
+       setIntent(intent);
+   }       
```

Notes:
- `@Override` is added to update intent on notification click

## IOS Configuration

### Pod approach:

Make sure you have [Cocoapods](https://cocoapods.org/) version > 1.0

Configure the project:
```
cd ios && pod init
```

(In case of syntax errors, `open YOURApp.xcodeproj/project.pbxproj` and fix them.)

Edit the newly created `Podfile`:
```diff
  # Pods for YOURAPP
+ pod 'Firebase'
+ pod 'Firebase/Messaging'
```

Install the `Firebase/Messaging` pod:
```
pod install
```
NOTE: you don't need to enable `use_frameworks!`. if you have to have `use_frameworks!` make sure you don't have `inherit! :search_paths`

NOTE: there is a working example in `master` branch

NOTE: If you don't put `pod 'Firebase'` into `Podfile`, compilation will fail with error of missing Firebase library.

### Non Cocoapod approach

1. Follow the instruction on [Integrate without CocoaPods](https://firebase.google.com/docs/ios/setup#frameworks).
- Import libraries, add Capabilities (background running and push notification), upload APNS and etc etc etc...
2. Put frameworks under `ios/Frameworks` folder, and drag those files into your xcode solution -> Frameworks
3. Put `firebase.h` and `module.modulemap` under `ios/Frameworks` folder, no need to drag into solution
4. Modify your project's `User Header Search Paths` and add `$(PROJECT_DIR)/Frameworks`
<img width="796" alt="screen shot 2018-03-05 at 2 17 03 pm" src="https://user-images.githubusercontent.com/9213224/36994792-263f05c4-2080-11e8-9d46-9b11ef49962a.png">
NOTE: There is a working example in `no-pod` branch

### Shared steps

Edit `AppDelegate.h`:
```diff
+ @import UserNotifications;
+
+ @interface AppDelegate : UIResponder <UIApplicationDelegate,UNUserNotificationCenterDelegate>
- @interface AppDelegate : UIResponder <UIApplicationDelegate>
```

Edit `AppDelegate.m`:
```diff
+ #import "RNFIRMessaging.h"
  //...

  - (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions
  {
  //...
+   [FIRApp configure];
+   [[UNUserNotificationCenter currentNotificationCenter] setDelegate:self];

    return YES;
 }

+
+ - (void)userNotificationCenter:(UNUserNotificationCenter *)center willPresentNotification:(UNNotification *)notification withCompletionHandler:(void (^)(UNNotificationPresentationOptions))completionHandler
+ {
+   [RNFIRMessaging willPresentNotification:notification withCompletionHandler:completionHandler];
+ }
+
+ #if defined(__IPHONE_11_0)
+ - (void)userNotificationCenter:(UNUserNotificationCenter *)center didReceiveNotificationResponse:(UNNotificationResponse *)response withCompletionHandler:(void (^)(void))completionHandler
+ {
+   [RNFIRMessaging didReceiveNotificationResponse:response withCompletionHandler:completionHandler];
+ }
+ #else
+ - (void)userNotificationCenter:(UNUserNotificationCenter *)center didReceiveNotificationResponse:(UNNotificationResponse *)response withCompletionHandler:(void(^)())completionHandler
+ {
+   [RNFIRMessaging didReceiveNotificationResponse:response withCompletionHandler:completionHandler];
+ }
+ #endif
+
+ //You can skip this method if you don't want to use local notification
+ -(void)application:(UIApplication *)application didReceiveLocalNotification:(UILocalNotification *)notification {
+   [RNFIRMessaging didReceiveLocalNotification:notification];
+ }
+
+ - (void)application:(UIApplication *)application didReceiveRemoteNotification:(nonnull NSDictionary *)userInfo fetchCompletionHandler:(nonnull void (^)(UIBackgroundFetchResult))completionHandler{
+   [RNFIRMessaging didReceiveRemoteNotification:userInfo fetchCompletionHandler:completionHandler];
+ }
```

**Add the path of header files into XCode:**

1. Open XCode.
2. Press `CMD+1` or click the XCode project.
3. Go to **Build Settings**, selecting **All** and **Combined**.
4. Search **Header Search Path** in the searchg tab.
5. Make sure there is a line of `$(SRCROOT)/../node_modules/react-native-fcm/ios`. If no, just add it.

**Add GoogleService-Info.plist:**

Make sure the file is not just moved into the folder. You need to `Right Click` the project folder in XCode and `Add File to <Project Name>`. Select **Copy if needed** in the `Options` page while selecting the file.

**Shared Library Settings:**

- Make sure you see `Pods.xcodeproj` under **Library** folder if you are using Pod install method.
- Make sure you see `RNFIRMessaging.xcodeproj` under **Library** folder.
- If you don't see any of these files, please add them by `Right Click` the **Library** folder and `Add File to <Project Name>` to add them back. `Pods.xcodeproj` should be under `ios/Pods/`, and `RNFIRMessaging.xcodeproj` should be under `node_modules/react-native-fcm/ios`.
- Make sure you see `libRNFIRMessaging.a` under **Link Binary With Libraries** under **Build Phases** tab. If no, drag the file under `RNFIRMessaging.xcodeproj` under **Library** folder into there.

### Add Capabilities
- Select your project **Capabilities** and enable:
  - **Push Notifications**
  - *Background Modes* > **Remote notifications**.

### FirebaseAppDelegateProxyEnabled
This instruction assumes that you have FirebaseAppDelegateProxyEnabled=YES (default) so that Firebase will hook on push notification registration events. If you turn this flag off, you will be on your own to manage APNS tokens and link with Firebase token.

## Setup Local Notifications
NOTE: local notification does NOT have any dependency on FCM library but you still need to include Firebase to compile. If there are enough demand to use this functionality alone, I will separate it out into another repo

### IOS
No change required

### Android
Edit AndroidManifest.xml
```diff
  <uses-permission android:name="android.permission.INTERNET" />
+ <uses-permission android:name="android.permission.RECEIVE_BOOT_COMPLETED" />
+ <uses-permission android:name="android.permission.VIBRATE" />

  <application>
+      <receiver android:name="com.evollu.react.fcm.FIRLocalMessagingPublisher"/>
+      <receiver android:enabled="true" android:exported="true"  android:name="com.evollu.react.fcm.FIRSystemBootEventReceiver">
+          <intent-filter>
+              <action android:name="android.intent.action.BOOT_COMPLETED"/>
+              <action android:name="android.intent.action.QUICKBOOT_POWERON"/>
+              <action android:name="com.htc.intent.action.QUICKBOOT_POWERON"/>
+              <category android:name="android.intent.category.DEFAULT" />
+          </intent-filter>
+      </receiver>
  </application>
```
NOTE: `com.evollu.react.fcm.FIRLocalMessagingPublisher` is required for presenting local notifications. `com.evollu.react.fcm.FIRSystemBootEventReceiver` is required only if you need to schedule future or recurring local notifications


## Usage
[Check example project](https://github.com/evollu/react-native-fcm/blob/master/Examples/simple-fcm-client/app/App.js#L68)


### Build custom push notification for Android
Firebase android misses important feature of android notification like `group`, `priority` and etc. As a work around you can send data message (no `notification` payload at all) and this repo will build a local notification for you. If you pass `custom_notification` in the payload, the repo will treat the content as a local notification config and shows immediately.

NOTE: By using this work around, you will have to send different types of payload for iOS and Android devices because **custom_notification isn't supported on iOS**

WARNING: `custom_notification` **cannot** be used together with `notification` attribute. use `data` **ALONE**

Example of payload that is sent to FCM server:
```
{
  "to":"FCM_TOKEN",
  "data": {
    "type":"MEASURE_CHANGE",
    "custom_notification": {
      "body": "test body",
      "title": "test title",
      "color":"#00ACD4",
      "priority":"high",
      "icon":"ic_notif",
      "group": "GROUP",
      "id": "id",
      "show_in_foreground": true
    }
  }
}
```

Example of payload that is sent through firebase console:
<img width="753" alt="screen shot 2018-04-04 at 1 18 09 pm" src="https://user-images.githubusercontent.com/9213224/38323255-bbbfdd66-380a-11e8-95c2-bf32ced959b8.png">

Check local notification guide below for configuration.

**IMPORTANT**: When using the `admin.messaging` API, you need to `JSON.stringify` the `custom_notification` value:

```
let tokens = [...];
let payload = {
  data: {
    custom_notification: JSON.stringify({
      body: 'Message body',
      title: 'Message title'
      ...
    })
  }
};
let options = { priority: "high" };

admin
  .messaging()
  .sendToDevice(tokens, payload, options);
```

### Behaviour when sending `notification` and `data` payload through GCM
- When user clicks notification to **launch** the application, you can get that notification by calling `FCM.getInitialNotification`. (NOTE: reloading javascript or resuming from background won't change the value)

- When app is running in background (the tricky one, I strongly suggest you try it out yourself)
 - IOS will receive notificaton from `FCMNotificationReceived` event
    * if you pass `content_available` flag true, you will receive one when app is in background and another one when user resume the app. [more info](http://www.rahuljiresal.com/2015/03/retract-push-notifications-on-ios/)
    * if you just pass `notification`, you will only receive one when user resume the app.
    * you will not see banner if `notification->body` is not defined.
 - Android will receive notificaton from `FCMNotificationReceived` event
    * if you pass `notification` payload, it will receive data when user click on notification
    * if you pass `data` payload only, it will receive data when in background

   e.g. fcm payload looks like:

   ```json
   {
      "to":"some_device_token",
      "content_available": true,
      "notification": {
          "title": "hello",
          "body": "yo",
          "click_action": "fcm.ACTION.HELLO"
      },
      "data": {
          "extra":"juice"
      }
    }
    ```

    and event callback will receive as:

    - Android
      ```json
      {
        "fcm": {"action": "fcm.ACTION.HELLO"},
        "opened_from_tray": 1,
        "extra": "juice"
      }
      ```

    - iOS
      ```json
      {
        "apns": {"action_category": "fcm.ACTION.HELLO"},
        "opened_from_tray": 1,
        "extra": "juice"
      }
      ```

- When app is running in foreground
 - IOS will receive notification and android **won't** (better not to do anything in foreground for hybrid and send a separate data message.)

NOTE: it is recommended not to rely on `data` payload for click_action as it can be overwritten (check [this](http://stackoverflow.com/questions/33738848/handle-multiple-notifications-with-gcm)).

### Quick notes about upstream messages
If your app server implements the [XMPP Connection Server](https://firebase.google.com/docs/cloud-messaging/server#implementing-the-xmpp-connection-server-protocol) protocol, it can receive upstream messages from a user's device to the cloud. To initiate an upstream message, call the `FCM.send()` method with your Firebase `Sender ID` and a `Data Object` as parameters as follows:

```javascript
FCM.send('984XXXXXXXXX', {
  my_custom_data_1: 'my_custom_field_value_1',
  my_custom_data_2: 'my_custom_field_value_2'
});
```

The `Data Object` is message data comprising as many key-value pairs of the message's payload as are needed (ensure that the value of each pair in the data object is a `string`). Your `Sender ID` is a unique numerical value generated when you created your Firebase project, it is available in the `Cloud Messaging` tab of the Firebase console `Settings` pane. The sender ID is used to identify each app server that can send messages to the client app.

### Sending remote notifications with category on iOS
If you want to send notification which will have actions as you defined in app it's important to correctly set it's `category` (`click_action`) property. It's also good to set `"content-available" : 1` so app will gets enough time to handle actions in background.

So the fcm payload should look like this:
```javascript
{
   "to": "some_device_token",
   "content_available": true,
   "notification": {
       "title": "Alarm",
       "subtitle": "First Alarm",
       "body": "First Alarm",
       "click_action": "com.myapp.MyCategory" // The id of notification category which you defined with FCM.setNotificationCategories
   },
   "data": {
       "extra": "juice"
   }
 }
 ```

## Q & A

#### Why do you build another local notification
Yes there are `react-native-push-notification` and `react-native-system-notification` which are great libraries. However
- We want a unified local notification library but people are reporting using react-native-push-notification with this repo has compatibility issue as `react-native-push-notification` also sets up GCM.
- We want to have local notification to have similar syntax as remote notification payload.
- The PushNotificationIOS by react native team is still missing features that recurring, so we are adding it here

#### My Android build is failing
Try update your SDK and google play service.
If you are having multiple plugins requiring different version of play-service sdk, skip conflicting group. The example project shows for how to colive with react-native-maps
```
    compile(project(':react-native-maps')) {
        exclude group: 'com.google.android.gms', module: 'play-services-base'
    }
```

#### My App throws FCM function undefined error
There seems to be link issue with rnpm. Make sure that there is `new FIRMessagingPackage(),` in your `Application.java` file

#### I can't get notification in iOS emulator
Remote notification can't reach iOS emulator since it can't fetch APNS token. Use real device.

#### I'm not getting notfication when app is in background
1. Make sure you've uploaded APNS certificates to Firebase and test with Firebase's native example to make sure certs are correct
2. Try simple payload first, sometimes notification doesn't show up because of empty body, wrong sound name etc.

#### App running in background doesn't trigger `FCMNotificationReceived` when receiving hybrid notification [Android]
These is [an issue opened for that](https://github.com/google/gcm/issues/63). Behavior is not consistent between 2 platforms

#### Android notification is showing a white icon
Since Lollipop, the push notification icon is required to be all white, otherwise it will be a white circle.

#### iOS not receiving notification when the app running in the background
- Try adding Background Modes permission in Xcode->Click on project file->Capabilities tab->Background Modes->Remote Notifications

#### I am using Proguard
You need to add this to your `android/app/proguard-rules.pro`:
```
# Google Play Services
-keep class com.google.android.gms.** { *; }
-dontwarn com.google.android.gms.**
```

#### I'm getting `com.android.dex.DexException: Multiple dex files define Lcom/google/android/gms/internal/zzqf;`
It is most likely that you are using other react-native-modules that requires conflicting google play service
search for `compile "com.google.android.gms` in android and see who specifies specific version. Resolve conflict by loosing their version or specify a version resolve in gradle.
Check this article https://medium.com/@suchydan/how-to-solve-google-play-services-version-collision-in-gradle-dependencies-ef086ae5c75f#.9l0u84y9t

#### How do I tell if user clicks the notification banner?
Check open from tray flag in notification. It will be either 0 or 1 for iOS and undefined or 1 for android. I decide for iOS based on [this](http://stackoverflow.com/questions/20569201/remote-notification-method-called-twice), and for android I set it if notification is triggered by intent change.

#### Android notification doesn't vibrate/show head-up display etc
All available features are [here](https://firebase.google.com/docs/cloud-messaging/http-server-ref#notification-payload-support). FCM may add more support in the future but there is no timeline.
In the mean time, you can pass "custom_notification" in a data message. This repo will show a local notification for you so you can set priority etc

#### How do I do xxx with FCM?
check out [official docs and see if they support](https://firebase.google.com/docs/cloud-messaging/concept-options)

#### I want to add advanced feature that FCM doesn't support for remote notification
You can either wait for FCM to develop it or you have to write native code to create notifications.
- for iOS, you can do it in `didReceiveRemoteNotification` in `appDelegate.m`
- for android, you can do it by implementing a service similar to "com.evollu.react.fcm.MessagingService"

Or if you have a good way to wake up react native javascript thread please let me know, although I'm worring waking up the whole application is too expensive.

#### What about new notifications in iOS 10
Congratulations, now you have 5 notification handler to register!
in sum
- `willPresentNotification` is introduced in iOS 10 and will only be called when local/remote notification will show up. This allows you to run some code **before** notification shows up. You can also decide how to show the notification.
- `didReceiveNotificationResponse` is introduced in iOS 10 and provides user's response together with local/remote notification. It could be swipe, text input etc.
- `didReceiveLocalNotification` is for iOS 9 and below. Triggered when user clicks local notification. replaced by `didReceiveNotificationResponse`
- `didReceiveRemoteNotification` is for iOS 9 and below. Triggered when remote notification received.
- `didReceiveRemoteNotification:fetchCompletionHandler` is for both iOS 9 and 10. it gets triggered 2 times for each remote notification. 1st time when notification is received. 2nd time when notification is clicked. in iOS 9, it serves us the purpose of both `willPresentNotification` and `didReceiveNotificationResponse` but for remote notification only. in iOS 10, you don't need it in most of the case unless you need to do background fetching

Great, how do I configure for FCM?
It is up to you! FCM is just a bridging library that passes notification into javascript world. You can define your own NSDictionary and pass it into notification.

#### I want to show notification when app is in foreground
Use `show_in_foreground` attribute to tell app to show banner even if the app is in foreground.

NOTE: this flag doesn't work for Android push notification, use `custom_notification` to achieve this.

NOTE: foreground notification is not available on iOS 9 and below

#### Do I need to handle APNS token registration?
No. Method swizzling in Firebase Cloud Messaging handles this unless you turn that off. Then you are on your own to implement the handling. Check this link https://firebase.google.com/docs/cloud-messaging/ios/client

#### I want to add actions in iOS notification
Check this https://github.com/evollu/react-native-fcm/issues/325

#### React/RCTBridgeModule.h not found
This is mostly caused by React Native upgrade. Here is a fix http://stackoverflow.com/questions/41477241/react-native-xcode-upgrade-and-now-rctconvert-h-not-found

#### Some features are missing
Issues and pull requests are welcome. Let's make this thing better!

#### Credits
Local notification implementation is inspired by react-native-push-notification by zo0r

#### I get the notifications in the logs, but the native prompt does not show up
Did you remember to ask the user permissions? ;)
```js
await FCM.requestPermissions({ badge: false, sound: true, alert: true })
```

## Sending remote notification

How to send a push notification from your server? You should `POST` to this endpoint:

    https://fcm.googleapis.com/fcm/send

You need to set the headers of `Content-Type` to `application/json` and `Authorization` to `key=******` where you replace `******` with the "Legacy server key" from here the Firebase dashbaord. Get this information by first going to:

1. https://console.firebase.google.com/
2. Click on "Gear" icon and click "Project Settingss". Screenshot: https://screenshotscdn.firefoxusercontent.com/images/35b93de8-44e1-49af-89d7-140b74c267c7.png
3. Click on "Cloud Message" tab and find "Legacy server key" here. Screenshot: https://screenshotscdn.firefoxusercontent.com/images/c52ec383-783d-47d3-a1e6-75249fb6f3fb.png

The body should be json like this:

```
{
  "to":"FCM_DEVICE_TOKEN_GOES_HERE",
  "data": {
    "custom_notification": {
      "body": "test body",
      "title": "test title",
      "color":"#00ACD4",
      "priority":"high",
      "icon":"ic_launcher",
      "group": "GROUP",
      "sound": "default",
      "id": "id",
      "show_in_foreground": true
    }
  }
}
```

Example:

```
fetch('https://fcm.googleapis.com/fcm/send', {
    method: 'POST',
    headers: {
        'Content-Type': 'application/json'
        'Authorization': 'key=EFefklefwef9efwefkejfwf'
    },
    body: JSON.stringify({
        "to":"kajfsdf:efawefwe_fsdfdsf-asfawefwefwf_asdfsdfasd-asdfasdfsd9A_asdfsdf_asdf",
        "data": {
            "custom_notification": {
            "body": "test body",
            "title": "test title",
            "color":"#00ACD4",
            "priority":"high",
            "icon":"ic_notif",
            "group": "GROUP",
            "sound": "default",
            "id": "id",
            "show_in_foreground": true
            }
        }
    })
})
```

## Channels

Right now for Android Orion 8 or API 26 is important to use channels. Firebase will create a default channel for you or you can custom your default channel for Firebase notifications by adding default meta data to `AndroidManifest`:

```
<meta-data android:name="com.google.firebase.messaging.default_notification_channel_id" android:value="@string/default_notification_channel_id"/>
```
more reading on [official docs](https://firebase.google.com/docs/cloud-messaging/android/client)

However it is essential to create a notification channel if you need to show local notification or use `custom_notification`.
First you should `createNotificationChannel` on init app. Its creates if not exists yet.

```
FCM.createNotificationChannel({
    id: 'car_status',
    name: 'Car status',
    description: 'Notifies when changes car status',
    priority: 'max',
});
```

After this all notifications should have `channel` key and value with specified channel name. For example:

```
customNotification = {
   id: 'id',
   title: `title`,
   body: 'body',
   sound: 'default',
   priority: 'high',
   icon: 'ic_launcher',
   show_in_foreground: true,
   vibrate: 500,
   channel: 'car_status', <====
   action: 'android.intent.action.MAIN',
};
```