fix(remote_config): fixing an issue that could cause duplicate listeners on hot restart (firebase#12545)

* fix(remote_config, android): Fix listener cleanup on hot restart.

* fix: implement clean up of listeners on apple side

* chore: apple setup for example app

* fix(remote_config, ios): clean listeners on hot restart

* chore: formatting

---------

Co-authored-by: russellwheatley <[email protected]>

Author: TarekkMA

packages/firebase_remote_config/firebase_remote_config/android/src/main/java/io/flutter/plugins/firebase/firebaseremoteconfig/FirebaseRemoteConfigPlugin.java

@@ -104,6 +104,7 @@ public Task<Void> didReinitializeFirebaseCore() {
     cachedThreadPool.execute(
         () -> {
           try {
+            removeEventListeners();
             taskCompletionSource.setResult(null);
           } catch (Exception e) {
             taskCompletionSource.setException(e);
@@ -308,6 +309,7 @@ public void onError(@NonNull FirebaseRemoteConfigException error) {
   @SuppressWarnings("unchecked")
   @Override
   public void onCancel(Object arguments) {
+    // arguments will be null on hot restart, so we will clean up listeners in didReinitializeFirebaseCore()
     Map<String, Object> argumentsMap = (Map<String, Object>) arguments;
     if (argumentsMap == null) {
       return;
@@ -320,4 +322,12 @@ public void onCancel(Object arguments) {
       listenersMap.remove(appName);
     }
   }
+
+  /** Remove all registered listeners. */
+  private void removeEventListeners() {
+    for (ConfigUpdateListenerRegistration listener : listenersMap.values()) {
+      listener.remove();
+    }
+    listenersMap.clear();
+  }
 }

packages/firebase_remote_config/firebase_remote_config/example/ios/Flutter/AppFrameworkInfo.plist

@@ -25,6 +25,6 @@
     <string>arm64</string>
   </array>
   <key>MinimumOSVersion</key>
-  <string>11.0</string>
+  <string>12.0</string>
 </dict>
 </plist>

packages/firebase_remote_config/firebase_remote_config/example/ios/Podfile

@@ -1,5 +1,5 @@
 # Uncomment this line to define a global platform for your project
- platform :ios, '11.0'
+ platform :ios, '12.0'
 
 # CocoaPods analytics sends network stats synchronously affecting flutter build latency.
 ENV['COCOAPODS_DISABLE_STATS'] = 'true'

packages/firebase_remote_config/firebase_remote_config/example/ios/Runner.xcodeproj/project.pbxproj

@@ -169,7 +169,7 @@
 		97C146E61CF9000F007C117D /* Project object */ = {
 			isa = PBXProject;
 			attributes = {
-				LastUpgradeCheck = 1300;
+				LastUpgradeCheck = 1510;
 				ORGANIZATIONNAME = "The Chromium Authors";
 				TargetAttributes = {
 					97C146ED1CF9000F007C117D = {
@@ -221,6 +221,7 @@
 			files = (
 			);
 			inputPaths = (
+				"${TARGET_BUILD_DIR}/${INFOPLIST_PATH}",
 			);
 			name = "Thin Binary";
 			outputPaths = (
@@ -274,6 +275,7 @@
 				"${BUILT_PRODUCTS_DIR}/FirebaseCoreInternal/FirebaseCoreInternal.framework",
 				"${BUILT_PRODUCTS_DIR}/FirebaseInstallations/FirebaseInstallations.framework",
 				"${BUILT_PRODUCTS_DIR}/FirebaseRemoteConfig/FirebaseRemoteConfig.framework",
+				"${BUILT_PRODUCTS_DIR}/FirebaseSharedSwift/FirebaseSharedSwift.framework",
 				"${BUILT_PRODUCTS_DIR}/GoogleUtilities/GoogleUtilities.framework",
 				"${BUILT_PRODUCTS_DIR}/PromisesObjC/FBLPromises.framework",
 			);
@@ -284,6 +286,7 @@
 				"${TARGET_BUILD_DIR}/${FRAMEWORKS_FOLDER_PATH}/FirebaseCoreInternal.framework",
 				"${TARGET_BUILD_DIR}/${FRAMEWORKS_FOLDER_PATH}/FirebaseInstallations.framework",
 				"${TARGET_BUILD_DIR}/${FRAMEWORKS_FOLDER_PATH}/FirebaseRemoteConfig.framework",
+				"${TARGET_BUILD_DIR}/${FRAMEWORKS_FOLDER_PATH}/FirebaseSharedSwift.framework",
 				"${TARGET_BUILD_DIR}/${FRAMEWORKS_FOLDER_PATH}/GoogleUtilities.framework",
 				"${TARGET_BUILD_DIR}/${FRAMEWORKS_FOLDER_PATH}/FBLPromises.framework",
 			);
@@ -432,6 +435,7 @@
 			baseConfigurationReference = 9740EEB21CF90195004384FC /* Debug.xcconfig */;
 			buildSettings = {
 				ASSETCATALOG_COMPILER_APPICON_NAME = AppIcon;
+				DEVELOPMENT_TEAM = YYX2P3XVJ7;
 				ENABLE_BITCODE = NO;
 				FRAMEWORK_SEARCH_PATHS = (
 					"$(inherited)",
@@ -456,6 +460,7 @@
 			baseConfigurationReference = 7AFA3C8E1D35360C0083082E /* Release.xcconfig */;
 			buildSettings = {
 				ASSETCATALOG_COMPILER_APPICON_NAME = AppIcon;
+				DEVELOPMENT_TEAM = YYX2P3XVJ7;
 				ENABLE_BITCODE = NO;
 				FRAMEWORK_SEARCH_PATHS = (
 					"$(inherited)",

packages/firebase_remote_config/firebase_remote_config/example/ios/Runner.xcodeproj/xcshareddata/xcschemes/Runner.xcscheme

@@ -1,6 +1,6 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <Scheme
-   LastUpgradeVersion = "1300"
+   LastUpgradeVersion = "1510"
    version = "1.3">
    <BuildAction
       parallelizeBuildables = "YES"

packages/firebase_remote_config/firebase_remote_config/ios/Classes/FLTFirebaseRemoteConfigPlugin.m

@@ -37,6 +37,8 @@ + (instancetype)sharedInstance {
 
 - (instancetype)init {
   self = [super init];
+  if (!self) return self;
+  _listenersMap = [NSMutableDictionary dictionary];
   return self;
 }
 
@@ -248,8 +250,16 @@ - (NSString *)mapValueSource:(FIRRemoteConfigSource)source {
 
 #pragma mark - FLTFirebasePlugin
 
+- (void)cleanupWithCompletion {
+  for (FIRConfigUpdateListenerRegistration *listener in self.listenersMap.allValues) {
+    [listener remove];
+  }
+  [self.listenersMap removeAllObjects];
+}
+
 - (void)didReinitializeFirebaseCore:(void (^)(void))completion {
   _fetchAndActivateRetry = false;
+  [self cleanupWithCompletion];
   completion();
 }
 
@@ -291,7 +301,9 @@ - (NSString *_Nonnull)flutterChannelName {
 }
 
 - (FlutterError *_Nullable)onCancelWithArguments:(id _Nullable)arguments {
-  NSString *appName = (NSString *)arguments;
+  NSString *appName = (NSString *)arguments[@"appName"];
+  // arguments will be null on hot restart, so we will clean up listeners in
+  // didReinitializeFirebaseCore()
   if (!appName) return nil;
   [self.listenersMap[appName] remove];
   [self.listenersMap removeObjectForKey:appName];