Revert "Refactor connectivity monitor on iOS"

1 files changed, 17 insertions, 8 deletions

diff --git a/src/objective-c/GRPCClient/private/GRPCHost.m b/src/objective-c/GRPCClient/private/GRPCHost.m
index 8568e334dd..71b57cf1f6 100644
--- a/src/objective-c/GRPCClient/private/GRPCHost.m
+++ b/src/objective-c/GRPCClient/private/GRPCHost.m
@@ -37,6 +37,12 @@ NS_ASSUME_NONNULL_BEGIN
 
 static NSMutableDictionary *kHostCache;
 
+// This connectivity monitor flushes the host cache when connectivity status
+// changes or when connection switch between Wifi and Cellular data, so that a
+// new call will use a new channel. Otherwise, a new call will still use the
+// cached channel which is no longer available and will cause gRPC to hang.
+static GRPCConnectivityMonitor *connectivityMonitor = nil;
+
 @implementation GRPCHost {
   // TODO(mlumish): Investigate whether caching channels with strong links is a good idea.
   GRPCChannel *_channel;
@@ -84,7 +90,17 @@ static NSMutableDictionary *kHostCache;
       kHostCache[address] = self;
       _compressAlgorithm = GRPC_COMPRESS_NONE;
     }
-    [GRPCConnectivityMonitor registerObserver:self selector:@selector(connectivityChange:)];
+    // Keep a single monitor to flush the cache if the connectivity status changes
+    // Thread safety guarded by @synchronized(kHostCache)
+    if (!connectivityMonitor) {
+      connectivityMonitor =
+      [GRPCConnectivityMonitor monitorWithHost:hostURL.host];
+      void (^handler)(void) = ^{
+        [GRPCHost flushChannelCache];
+      };
+      [connectivityMonitor handleLossWithHandler:handler
+                         wifiStatusChangeHandler:handler];
+    }
   }
   return self;
 }
@@ -265,13 +281,6 @@ static NSMutableDictionary *kHostCache;
   }
 }
 
-// Flushes the host cache when connectivity status changes or when connection switch between Wifi
-// and Cellular data, so that a new call will use a new channel. Otherwise, a new call will still
-// use the cached channel which is no longer available and will cause gRPC to hang.
-- (void)connectivityChange:(NSNotification *)note {
-  [GRPCHost flushChannelCache];
-}
-
 @end
 
 NS_ASSUME_NONNULL_END