Resolve and reject promise for PushNotificationIOS.requestPermissions

Summary:
**Resolve/Reject Promise**
* Add onFulfill and onReject to the `PushNotificationIOS.requestPermissions()` Promise

**Replace Apple-deprecated notification method**
* Old: In iOS 10, `UIApplication.registerUserNotificationSettings` was deprecated. Calling this would then call the AppDelegate's lifecycle function `didRegisterUserNotificationSettings`, and then in the AppDelegate, we'd call `RCTPushNotificationManager.didRegisterUserNotificationSettings` to return the user settings.
[registerusernotificationsettings Doc](https://developer.apple.com/documentation/uikit/uiapplication/1622932-registerusernotificationsettings?language=objc)

* New: Replace deprecated function with Apple's recommended `UNUserNotificationCenter.currentNotificationCenter getNotificationSettingsWithCompletionHandler`, which no longer needs the AppDelegate lifecycle method because it directly returns the user's settings in a completion hander.
[requestauthorizationwithoptions Doc](https://developer.apple.com/documentation/usernotifications/unusernotificationcenter/1649527-requestauthorizationwithoptions?language=objc)

**Add Tests**
* Add tests on `PushNotificationIOSExample.js` to test that the onFulfill and onReject are called
* On `PushNotificationIOSExample.js`, instead of asking permission upon page load, ask for permission when the user taps the button "Request Notifications (Should Display Alert)".
* Before, asking for permission multiple times before would result in the RN error "cannot call requestPermissions twice before the first has returned", now you can ask for permission as many times as you want because I've removed the now unused `RCTPromiseResolveBlock`.

**Future**
If this works on device (we have to land this to test push on device), we can delete `RTCPushNotificationManager.didRegisterUserNotificationSettings` which is being called from several apps.

Changelog:
[iOS] [Added]  Resolve and reject promise for PushNotificationIOS.requestPermissions

Reviewed By: PeteTheHeat

Differential Revision: D19700061

fbshipit-source-id: 02ba815787efc9047f33ffcdfafe962b134afe6d

Author: p-sun

Libraries/PushNotificationIOS/RCTPushNotificationManager.mm

@@ -21,7 +21,6 @@
 
 static NSString *const kLocalNotificationReceived = @"LocalNotificationReceived";
 static NSString *const kRemoteNotificationsRegistered = @"RemoteNotificationsRegistered";
-static NSString *const kRegisterUserNotificationSettings = @"RegisterUserNotificationSettings";
 static NSString *const kRemoteNotificationRegistrationFailed = @"RemoteNotificationRegistrationFailed";
 
 static NSString *const kErrorUnableToRequestPermissions = @"E_UNABLE_TO_REQUEST_PERMISSIONS";
@@ -83,9 +82,6 @@ @interface RCTPushNotificationManager () <NativePushNotificationManagerIOS>
 #endif //TARGET_OS_TV / TARGET_OS_UIKITFORMAC
 
 @implementation RCTPushNotificationManager
-{
-  RCTPromiseResolveBlock _requestPermissionsResolveBlock;
-}
 
 #if !TARGET_OS_TV && !TARGET_OS_UIKITFORMAC
 
@@ -152,10 +148,6 @@ - (void)startObserving
                                            selector:@selector(handleRemoteNotificationReceived:)
                                                name:RCTRemoteNotificationReceived
                                              object:nil];
-  [[NSNotificationCenter defaultCenter] addObserver:self
-                                           selector:@selector(handleRegisterUserNotificationSettings:)
-                                               name:kRegisterUserNotificationSettings
-                                             object:nil];
   [[NSNotificationCenter defaultCenter] addObserver:self
                                            selector:@selector(handleRemoteNotificationsRegistered:)
                                                name:kRemoteNotificationsRegistered
@@ -181,12 +173,6 @@ - (void)stopObserving
 
 + (void)didRegisterUserNotificationSettings:(__unused UIUserNotificationSettings *)notificationSettings
 {
-  if ([UIApplication instancesRespondToSelector:@selector(registerForRemoteNotifications)]) {
-    [RCTSharedApplication() registerForRemoteNotifications];
-    [[NSNotificationCenter defaultCenter] postNotificationName:kRegisterUserNotificationSettings
-                                                        object:self
-                                                      userInfo:@{@"notificationSettings": notificationSettings}];
-  }
 }
 
 + (void)didRegisterForRemoteNotificationsWithDeviceToken:(NSData *)deviceToken
@@ -272,25 +258,6 @@ - (void)handleRemoteNotificationRegistrationError:(NSNotification *)notification
   [self sendEventWithName:@"remoteNotificationRegistrationError" body:errorDetails];
 }
 
-- (void)handleRegisterUserNotificationSettings:(NSNotification *)notification
-{
-  if (_requestPermissionsResolveBlock == nil) {
-    return;
-  }
-
-  UIUserNotificationSettings *notificationSettings = notification.userInfo[@"notificationSettings"];
-  NSDictionary *notificationTypes = @{
-    @"alert": @((notificationSettings.types & UIUserNotificationTypeAlert) > 0),
-    @"sound": @((notificationSettings.types & UIUserNotificationTypeSound) > 0),
-    @"badge": @((notificationSettings.types & UIUserNotificationTypeBadge) > 0),
-  };
-
-  _requestPermissionsResolveBlock(notificationTypes);
-  // Clean up listener added in requestPermissions
-  [self removeListeners:1];
-  _requestPermissionsResolveBlock = nil;
-}
-
 RCT_EXPORT_METHOD(onFinishRemoteNotification:(NSString *)notificationId fetchResult:(NSString *)fetchResult) {
   UIBackgroundFetchResult result = [RCTConvert UIBackgroundFetchResult:fetchResult];
   RCTRemoteNotificationCallback completionHandler = self.remoteNotificationCallbacks[notificationId];
@@ -322,19 +289,13 @@ - (void)handleRegisterUserNotificationSettings:(NSNotification *)notification
                  resolve:(RCTPromiseResolveBlock)resolve
                  reject:(RCTPromiseRejectBlock)reject)
 {
-  if (RCTRunningInAppExtension()) {
-    reject(kErrorUnableToRequestPermissions, nil, RCTErrorWithMessage(@"Requesting push notifications is currently unavailable in an app extension"));
-    return;
-  }
-
-  if (_requestPermissionsResolveBlock != nil) {
-    RCTLogError(@"Cannot call requestPermissions twice before the first has returned.");
-    return;
-  }
+   if (RCTRunningInAppExtension()) {
+     reject(kErrorUnableToRequestPermissions, nil, RCTErrorWithMessage(@"Requesting push notifications is currently unavailable in an app extension"));
+     return;
+   }
 
   // Add a listener to make sure that startObserving has been called
   [self addListener:@"remoteNotificationsRegistered"];
-  _requestPermissionsResolveBlock = resolve;
 
   UIUserNotificationType types = UIUserNotificationTypeNone;
 
@@ -348,9 +309,18 @@ - (void)handleRegisterUserNotificationSettings:(NSNotification *)notification
     types |= UIUserNotificationTypeSound;
   }
 
-  UIUserNotificationSettings *notificationSettings =
-    [UIUserNotificationSettings settingsForTypes:types categories:nil];
-  [RCTSharedApplication() registerUserNotificationSettings:notificationSettings];
+  [UNUserNotificationCenter.currentNotificationCenter
+   requestAuthorizationWithOptions:types
+   completionHandler:^(BOOL granted, NSError *_Nullable error) {
+    if (error != NULL) {
+      reject(@"-1", @"Error - Push authorization request failed.", error);
+    } else {
+      [RCTSharedApplication() registerForRemoteNotifications];
+      [UNUserNotificationCenter.currentNotificationCenter getNotificationSettingsWithCompletionHandler:^(UNNotificationSettings * _Nonnull settings) {
+         resolve(RCTPromiseResolveValueForUNNotificationSettings(settings));
+      }];
+    }
+  }];
 }
 
 RCT_EXPORT_METHOD(abandonPermissions)
@@ -361,16 +331,23 @@ - (void)handleRegisterUserNotificationSettings:(NSNotification *)notification
 RCT_EXPORT_METHOD(checkPermissions:(RCTResponseSenderBlock)callback)
 {
   if (RCTRunningInAppExtension()) {
-    callback(@[@{@"alert": @NO, @"badge": @NO, @"sound": @NO}]);
+    callback(@[RCTSettingsDictForUNNotificationSettings(NO, NO, NO)]);
     return;
   }
 
-  NSUInteger types = [RCTSharedApplication() currentUserNotificationSettings].types;
-  callback(@[@{
-    @"alert": @((types & UIUserNotificationTypeAlert) > 0),
-    @"badge": @((types & UIUserNotificationTypeBadge) > 0),
-    @"sound": @((types & UIUserNotificationTypeSound) > 0),
-  }]);
+  [UNUserNotificationCenter.currentNotificationCenter getNotificationSettingsWithCompletionHandler:^(UNNotificationSettings * _Nonnull settings) {
+    callback(@[RCTPromiseResolveValueForUNNotificationSettings(settings)]);
+  }];
+}
+
+static inline NSDictionary *RCTPromiseResolveValueForUNNotificationSettings(UNNotificationSettings* _Nonnull settings) {
+  return RCTSettingsDictForUNNotificationSettings(settings.alertSetting == UNNotificationSettingEnabled,
+                                                  settings.badgeSetting == UNNotificationSettingEnabled,
+                                                  settings.soundSetting == UNNotificationSettingEnabled);
+}
+
+static inline NSDictionary *RCTSettingsDictForUNNotificationSettings(BOOL alert, BOOL badge, BOOL sound) {
+  return @{@"alert": @(alert), @"badge": @(badge), @"sound": @(sound)};
 }
 
 RCT_EXPORT_METHOD(presentLocalNotification:(JS::NativePushNotificationManagerIOS::Notification &)notification)

RNTester/js/examples/PushNotificationIOS/PushNotificationIOSExample.js

@@ -49,8 +49,6 @@ class NotificationExample extends React.Component<{...}> {
       'localNotification',
       this._onLocalNotification,
     );
-
-    PushNotificationIOS.requestPermissions();
   }
 
   componentWillUnmount() {
@@ -173,18 +171,51 @@ class NotificationPermissionExample extends React.Component<
     return (
       <View>
         <Button
-          onPress={this._showPermissions.bind(this)}
-          label="Show enabled permissions"
+          onPress={this._requestPermissions}
+          label="Request Notifications (Should Display Alert)"
         />
-        <Text>{JSON.stringify(this.state.permissions)}</Text>
+        <Button onPress={this._checkPermissions} label="Check permissions" />
+        <Text style={{textAlign: 'center'}}>
+          {JSON.stringify(this.state.permissions)}
+        </Text>
       </View>
     );
   }
 
-  _showPermissions() {
+  _requestPermissions = () => {
+    PushNotificationIOS.requestPermissions().then(
+      onFulfill => {
+        this._showAlert(
+          'Successfully requested permissions -- ' +
+            'Alert: ' +
+            onFulfill.alert.toString() +
+            ', Badge: ' +
+            onFulfill.badge.toString() +
+            ', Sound: ' +
+            onFulfill.sound.toString(),
+        );
+        this._checkPermissions();
+      },
+      (onReject?) => {
+        this._showAlert('Error requesting permissions');
+        this._checkPermissions();
+      },
+    );
+  };
+
+  _checkPermissions = () => {
     PushNotificationIOS.checkPermissions(permissions => {
       this.setState({permissions});
     });
+  };
+
+  _showAlert(text) {
+    Alert.alert('Notification Permission', text, [
+      {
+        text: 'Dismiss',
+        onPress: null,
+      },
+    ]);
   }
 }
 
@@ -202,6 +233,18 @@ const styles = StyleSheet.create({
 exports.title = 'PushNotificationIOS';
 exports.description = 'Apple PushNotification and badge value';
 exports.examples = [
+  {
+    title: 'Notifications Permissions',
+    render(): React.Element<any> {
+      return <NotificationPermissionExample />;
+    },
+  },
+  {
+    title: 'Push Notifications',
+    render(): React.Element<any> {
+      return <NotificationExample />;
+    },
+  },
   {
     title: 'Badge Number',
     render(): React.Element<any> {
@@ -221,16 +264,4 @@ exports.examples = [
       );
     },
   },
-  {
-    title: 'Push Notifications',
-    render(): React.Element<any> {
-      return <NotificationExample />;
-    },
-  },
-  {
-    title: 'Notifications Permissions',
-    render(): React.Element<any> {
-      return <NotificationPermissionExample />;
-    },
-  },
 ];