Merge pull request firebase#732 from OleksiyA/FCM-subscribe-completion-1

[FCM] Add completion handler to subscribe/unsubscribe topic actions

Author: OleksiyA

Example/Messaging/Tests/FIRMessagingServiceTest.m

@@ -198,7 +198,8 @@ - (void)testSubscribeWithNoTopicPrefix {
   NSString *topicNameWithPrefix = [FIRMessagingPubSub addPrefixToTopic:topicName];
   messaging.pubsub = mockPubSub;
   messaging.defaultFcmToken = @"fake-default-token";
-  OCMExpect([messaging.pubsub subscribeToTopic:[OCMArg isEqual:topicNameWithPrefix]]);
+  OCMExpect([messaging.pubsub subscribeToTopic:[OCMArg isEqual:topicNameWithPrefix]
+                                       handler:[OCMArg any]]);
   [messaging subscribeToTopic:topicName];
   OCMVerifyAll(mockPubSub);
   // Need to swap back since it's a singleton and hence will live beyond the scope of this test.
@@ -213,7 +214,7 @@ - (void)testSubscribeWithTopicPrefix {
   NSString *topicName = @"/topics/topicWithoutPrefix";
   messaging.pubsub = mockPubSub;
   messaging.defaultFcmToken = @"fake-default-token";
-  OCMExpect([messaging.pubsub subscribeToTopic:[OCMArg isEqual:topicName]]);
+  OCMExpect([messaging.pubsub subscribeToTopic:[OCMArg isEqual:topicName] handler:[OCMArg any]]);
   [messaging subscribeToTopic:topicName];
   OCMVerifyAll(mockPubSub);
   // Need to swap back since it's a singleton and hence will live beyond the scope of this test.
@@ -229,7 +230,8 @@ - (void)testUnsubscribeWithNoTopicPrefix {
   NSString *topicNameWithPrefix = [FIRMessagingPubSub addPrefixToTopic:topicName];
   messaging.pubsub = mockPubSub;
   messaging.defaultFcmToken = @"fake-default-token";
-  OCMExpect([messaging.pubsub unsubscribeFromTopic:[OCMArg isEqual:topicNameWithPrefix]]);
+  OCMExpect([messaging.pubsub unsubscribeFromTopic:[OCMArg isEqual:topicNameWithPrefix]
+                                           handler:[OCMArg any]]);
   [messaging unsubscribeFromTopic:topicName];
   OCMVerifyAll(mockPubSub);
   // Need to swap back since it's a singleton and hence will live beyond the scope of this test.
@@ -244,7 +246,8 @@ - (void)testUnsubscribeWithTopicPrefix {
   NSString *topicName = @"/topics/topicWithPrefix";
   messaging.pubsub = mockPubSub;
   messaging.defaultFcmToken = @"fake-default-token";
-  OCMExpect([messaging.pubsub unsubscribeFromTopic:[OCMArg isEqual:topicName]]);
+  OCMExpect([messaging.pubsub unsubscribeFromTopic:[OCMArg isEqual:topicName]
+                                           handler:[OCMArg any]]);
   [messaging unsubscribeFromTopic:topicName];
   OCMVerifyAll(mockPubSub);
   // Need to swap back since it's a singleton and hence will live beyond the scope of this test.

Firebase/Messaging/FIRMessaging.m

@@ -683,10 +683,15 @@ + (NSString *)normalizeTopic:(NSString *)topic {
 }
 
 - (void)subscribeToTopic:(NSString *)topic {
+  [self subscribeToTopic:topic completion:nil];
+}
+
+- (void)subscribeToTopic:(NSString *)topic
+              completion:(nullable FIRMessagingTopicOperationCompletion)completion {
   if (self.defaultFcmToken.length && topic.length) {
     NSString *normalizeTopic = [[self class ] normalizeTopic:topic];
     if (normalizeTopic.length) {
-      [self.pubsub subscribeToTopic:normalizeTopic];
+      [self.pubsub subscribeToTopic:normalizeTopic handler:completion];
     } else {
       FIRMessagingLoggerError(kFIRMessagingMessageCodeMessaging009,
                               @"Cannot parse topic name %@. Will not subscribe.", topic);
@@ -699,10 +704,15 @@ - (void)subscribeToTopic:(NSString *)topic {
 }
 
 - (void)unsubscribeFromTopic:(NSString *)topic {
+  [self unsubscribeFromTopic:topic completion:nil];
+}
+
+- (void)unsubscribeFromTopic:(NSString *)topic
+                  completion:(nullable FIRMessagingTopicOperationCompletion)completion {
   if (self.defaultFcmToken.length && topic.length) {
     NSString *normalizeTopic = [[self class] normalizeTopic:topic];
     if (normalizeTopic.length) {
-      [self.pubsub unsubscribeFromTopic:normalizeTopic];
+      [self.pubsub unsubscribeFromTopic:normalizeTopic handler:completion];
     } else {
       FIRMessagingLoggerError(kFIRMessagingMessageCodeMessaging011,
                               @"Cannot parse topic name %@. Will not unsubscribe.", topic);

Firebase/Messaging/FIRMessagingPubSub.h

@@ -59,6 +59,7 @@
  *                   library for a given `authorizedEntity` and "gcm" scope.
  *  @param topic    The topic to subscribe to. Should be of the form
  *                  `"/topics/<topic-name>"`.
+ *  @param options  Unused parameter, please pass nil or empty dictionary.
  *  @param handler  The callback handler invoked when the subscribe call
  *                  ends. In case of success, a nil error is returned. Otherwise,
  *                  an appropriate error object is returned.
@@ -70,7 +71,6 @@
                    options:(NSDictionary *)options
                    handler:(FIRMessagingTopicOperationCompletion)handler;
 
-
 /**
  *  Unsubscribes an app instance from a topic, stopping it from receiving
  *  any further messages sent to that topic.
@@ -81,6 +81,7 @@
  *  @param token   The token used to subscribe to this topic.
  *  @param topic   The topic to unsubscribe from. Should be of the form
  *                 `"/topics/<topic-name>"`.
+ *  @param options Unused parameter, please pass nil or empty dictionary.
  *  @param handler The handler that is invoked once the unsubscribe call ends.
  *                 In case of success, nil error is returned. Otherwise, an
  *                  appropriate error object is returned.
@@ -98,17 +99,25 @@
  *  as compared to the `subscribe` method above which tries once.
  *
  *  @param topic The topic name to subscribe to. Should be of the form `"/topics/<topic-name>"`.
+ *  @param handler The handler that is invoked once the unsubscribe call ends.
+ *                 In case of success, nil error is returned. Otherwise, an
+ *                  appropriate error object is returned.
  */
-- (void)subscribeToTopic:(NSString *)topic;
+- (void)subscribeToTopic:(NSString *)topic
+                 handler:(nullable FIRMessagingTopicOperationCompletion)handler;
 
 /**
  *  Asynchronously unsubscribe from the topic. Adds to the pending list of topic operations.
  *  Retry in case of failures. This makes a repeated attempt to unsubscribe from the topic
  *  as compared to the `unsubscribe` method above which tries once.
  *
  *  @param topic The topic name to unsubscribe from. Should be of the form `"/topics/<topic-name>"`.
+ *  @param handler The handler that is invoked once the unsubscribe call ends.
+ *                 In case of success, nil error is returned. Otherwise, an
+ *                  appropriate error object is returned.
  */
-- (void)unsubscribeFromTopic:(NSString *)topic;
+- (void)unsubscribeFromTopic:(NSString *)topic
+                     handler:(nullable FIRMessagingTopicOperationCompletion)handler;
 
 /**
  *  Schedule subscriptions sync.

Firebase/Messaging/FIRMessagingPubSub.m

@@ -146,16 +146,18 @@ - (void)unsubscribeWithToken:(NSString *)token
   }];
 }
 
-- (void)subscribeToTopic:(NSString *)topic {
+- (void)subscribeToTopic:(NSString *)topic
+                 handler:(nullable FIRMessagingTopicOperationCompletion)handler {
   [self.pendingTopicUpdates addOperationForTopic:topic
                                       withAction:FIRMessagingTopicActionSubscribe
-                                      completion:nil];
+                                      completion:handler];
 }
 
-- (void)unsubscribeFromTopic:(NSString *)topic {
+- (void)unsubscribeFromTopic:(NSString *)topic
+                     handler:(nullable FIRMessagingTopicOperationCompletion)handler {
   [self.pendingTopicUpdates addOperationForTopic:topic
                                       withAction:FIRMessagingTopicActionUnsubscribe
-                                      completion:nil];
+                                      completion:handler];
 }
 
 - (void)scheduleSync:(BOOL)immediately {

Firebase/Messaging/FIRMessagingTopicOperation.m

@@ -82,6 +82,7 @@ - (instancetype)initWithTopic:(NSString *)topic
     _topic = topic;
     _action = action;
     _token = token;
+    _options = options;
     _checkinService = checkinService;
     _completion = completion;