Add an event for remote notification registration, and improve permissions request

Summary:
In order to add Push support to the Parse JS SDK in React Native, we need a way to receive the APNS device token from the JS context. This adds another event to PushNotificationIOS, so that code can respond to a successful registration.

Additionally, I've updated the `requestPermissions` call to accept an optional map of parameters. This way, developers can request a subset of user notification types.
Closes https://github.com/facebook/react-native/pull/1304
Github Author: Andrew Imm <andrewi@fb.com>

Test Plan: Imported from GitHub, without a `Test Plan:` line.

Libraries/PushNotificationIOS/PushNotificationIOS.js

@@ -20,6 +20,7 @@ var _initialNotification = RCTPushNotificationManager &&
   RCTPushNotificationManager.initialNotification;
 
 var DEVICE_NOTIF_EVENT = 'remoteNotificationReceived';
+var NOTIF_REGISTER_EVENT = 'remoteNotificationsRegistered';
 
 /**
  * Handle push notifications for your app, including permission handling and
@@ -49,30 +50,72 @@ class PushNotificationIOS {
   }
 
   /**
-   * Attaches a listener to remote notifications while the app is running in the
-   * foreground or the background.
+   * Attaches a listener to remote notification events while the app is running
+   * in the foreground or the background.
    *
-   * The handler will get be invoked with an instance of `PushNotificationIOS`
+   * Valid events are:
+   *
+   * - `notification` : Fired when a remote notification is received. The
+   *   handler will be invoked with an instance of `PushNotificationIOS`.
+   * - `register`: Fired when the user registers for remote notifications. The
+   *   handler will be invoked with a hex string representing the deviceToken.
    */
   static addEventListener(type: string, handler: Function) {
     invariant(
-      type === 'notification',
-      'PushNotificationIOS only supports `notification` events'
-    );
-    _notifHandlers[handler] = RCTDeviceEventEmitter.addListener(
-      DEVICE_NOTIF_EVENT,
-      (notifData) => {
-        handler(new PushNotificationIOS(notifData));
-      }
+      type === 'notification' || type === 'register',
+      'PushNotificationIOS only supports `notification` and `register` events'
     );
+    if (type === 'notification') {
+      _notifHandlers[handler] = RCTDeviceEventEmitter.addListener(
+        DEVICE_NOTIF_EVENT,
+        (notifData) => {
+          handler(new PushNotificationIOS(notifData));
+        }
+      );
+    } else if (type === 'register') {
+      _notifHandlers[handler] = RCTDeviceEventEmitter.addListener(
+        NOTIF_REGISTER_EVENT,
+        (registrationInfo) => {
+          handler(registrationInfo.deviceToken);
+        }
+      );
+    }
   }
 
   /**
-   * Requests all notification permissions from iOS, prompting the user's
-   * dialog box.
+   * Requests notification permissions from iOS, prompting the user's
+   * dialog box. By default, it will request all notification permissions, but
+   * a subset of these can be requested by passing a map of requested
+   * permissions.
+   * The following permissions are supported:
+   *
+   *   - `alert`
+   *   - `badge`
+   *   - `sound`
+   *
+   * If a map is provided to the method, only the permissions with truthy values
+   * will be requested.
    */
-  static requestPermissions() {
-    RCTPushNotificationManager.requestPermissions();
+  static requestPermissions(permissions?: {
+    alert?: boolean,
+    badge?: boolean,
+    sound?: boolean
+  }) {
+    var requestedPermissions = {};
+    if (permissions) {
+      requestedPermissions = {
+        alert: !!permissions.alert,
+        badge: !!permissions.badge,
+        sound: !!permissions.sound
+      };
+    } else {
+      requestedPermissions = {
+        alert: true,
+        badge: true,
+        sound: true
+      };
+    }
+    RCTPushNotificationManager.requestPermissions(requestedPermissions);
   }
 
   /**
@@ -97,8 +140,8 @@ class PushNotificationIOS {
    */
   static removeEventListener(type: string, handler: Function) {
     invariant(
-      type === 'notification',
-      'PushNotificationIOS only supports `notification` events'
+      type === 'notification' || type === 'register',
+      'PushNotificationIOS only supports `notification` and `register` events'
     );
     if (!_notifHandlers[handler]) {
       return;

Libraries/PushNotificationIOS/RCTPushNotificationManager.h

@@ -14,6 +14,7 @@
 @interface RCTPushNotificationManager : NSObject <RCTBridgeModule>
 
 + (void)application:(UIApplication *)application didRegisterUserNotificationSettings:(UIUserNotificationSettings *)notificationSettings;
++ (void)application:(UIApplication *)application didRegisterForRemoteNotificationsWithDeviceToken:(NSData *)deviceToken;
 + (void)application:(UIApplication *)application didReceiveRemoteNotification:(NSDictionary *)notification;
 
 @end

Libraries/PushNotificationIOS/RCTPushNotificationManager.m

@@ -12,7 +12,18 @@
 #import "RCTBridge.h"
 #import "RCTEventDispatcher.h"
 
+#if __IPHONE_OS_VERSION_MIN_REQUIRED < __IPHONE_8_0
+
+#define UIUserNotificationTypeAlert UIRemoteNotificationTypeAlert
+#define UIUserNotificationTypeBadge UIRemoteNotificationTypeBadge
+#define UIUserNotificationTypeSound UIRemoteNotificationTypeSound
+#define UIUserNotificationTypeNone  UIRemoteNotificationTypeNone
+#define UIUserNotificationType      UIRemoteNotificationType
+
+#endif
+
 NSString *const RCTRemoteNotificationReceived = @"RemoteNotificationReceived";
+NSString *const RCTRemoteNotificationsRegistered = @"RemoteNotificationsRegistered";
 
 @implementation RCTPushNotificationManager
 {
@@ -30,6 +41,10 @@ RCT_EXPORT_MODULE()
                                              selector:@selector(handleRemoteNotificationReceived:)
                                                  name:RCTRemoteNotificationReceived
                                                object:nil];
+    [[NSNotificationCenter defaultCenter] addObserver:self
+                                             selector:@selector(handleRemoteNotificationsRegistered:)
+                                                 name:RCTRemoteNotificationsRegistered
+                                               object:nil];
   }
   return self;
 }
@@ -52,6 +67,21 @@ RCT_EXPORT_MODULE()
   }
 }
 
++ (void)application:(UIApplication *)application didRegisterForRemoteNotificationsWithDeviceToken:(NSData *)deviceToken
+{
+  NSMutableString *hexString = [NSMutableString string];
+  const unsigned char *bytes = [deviceToken bytes];
+  for (int i = 0; i < [deviceToken length]; i++) {
+    [hexString appendFormat:@"%02x", bytes[i]];
+  }
+  NSDictionary *userInfo = @{
+    @"deviceToken" : [hexString copy]
+  };
+  [[NSNotificationCenter defaultCenter] postNotificationName:RCTRemoteNotificationsRegistered
+                                                      object:self
+                                                    userInfo:userInfo];
+}
+
 + (void)application:(UIApplication *)application didReceiveRemoteNotification:(NSDictionary *)notification
 {
   [[NSNotificationCenter defaultCenter] postNotificationName:RCTRemoteNotificationReceived
@@ -65,6 +95,12 @@ RCT_EXPORT_MODULE()
                                               body:[notification userInfo]];
 }
 
+- (void)handleRemoteNotificationsRegistered:(NSNotification *)notification
+{
+  [_bridge.eventDispatcher sendDeviceEventWithName:@"remoteNotificationsRegistered"
+                                              body:[notification userInfo]];
+}
+
 /**
  * Update the application icon badge number on the home screen
  */
@@ -83,36 +119,35 @@ RCT_EXPORT_METHOD(getApplicationIconBadgeNumber:(RCTResponseSenderBlock)callback
   ]);
 }
 
-RCT_EXPORT_METHOD(requestPermissions)
+RCT_EXPORT_METHOD(requestPermissions:(NSDictionary *)permissions)
 {
-  Class _UIUserNotificationSettings;
-  if ((_UIUserNotificationSettings = NSClassFromString(@"UIUserNotificationSettings"))) {
-    UIUserNotificationType types = UIUserNotificationTypeSound | UIUserNotificationTypeBadge | UIUserNotificationTypeAlert;
-    UIUserNotificationSettings *notificationSettings = [_UIUserNotificationSettings settingsForTypes:types categories:nil];
-    [[UIApplication sharedApplication] registerUserNotificationSettings:notificationSettings];
+  UIUserNotificationType types = UIRemoteNotificationTypeNone;
+  if (permissions) {
+    if ([permissions[@"alert"] boolValue]) {
+      types |= UIUserNotificationTypeAlert;
+    }
+    if ([permissions[@"badge"] boolValue]) {
+      types |= UIUserNotificationTypeBadge;
+    }
+    if ([permissions[@"sound"] boolValue]) {
+      types |= UIUserNotificationTypeSound;
+    }
   } else {
+    types = UIUserNotificationTypeAlert | UIUserNotificationTypeBadge | UIUserNotificationTypeSound;
+  }
 
-#if __IPHONE_OS_VERSION_MIN_REQUIRED < __IPHONE_8_0
-
-    [[UIApplication sharedApplication] registerForRemoteNotificationTypes:
-     UIUserNotificationTypeBadge | UIUserNotificationTypeSound | UIUserNotificationTypeAlert];
-
+#if __IPHONE_OS_VERSION_MIN_REQUIRED >= __IPHONE_8_0
+  id notificationSettings = [UIUserNotificationSettings settingsForTypes:types categories:nil];
+  [[UIApplication sharedApplication] registerUserNotificationSettings:notificationSettings];
+  [[UIApplication sharedApplication] registerForRemoteNotifications];
+#else
+  [[UIApplication sharedApplication] registerForRemoteNotificationTypes:types];
 #endif
 
-  }
 }
 
 RCT_EXPORT_METHOD(checkPermissions:(RCTResponseSenderBlock)callback)
 {
-
-#if __IPHONE_OS_VERSION_MIN_REQUIRED < __IPHONE_8_0
-
-#define UIUserNotificationTypeAlert UIRemoteNotificationTypeAlert
-#define UIUserNotificationTypeBadge UIRemoteNotificationTypeBadge
-#define UIUserNotificationTypeSound UIRemoteNotificationTypeSound
-
-#endif
-
   NSUInteger types = 0;
   if ([UIApplication instancesRespondToSelector:@selector(currentUserNotificationSettings)]) {
     types = [[[UIApplication sharedApplication] currentUserNotificationSettings] types];