Use a delegate for client callbacks in the CHIP Darwin Framework

src/darwin/CHIPTool/CHIPTool/CHIPViewControllerBase.m

@@ -24,7 +24,7 @@
 
 static NSString * const ipKey = @"ipk";
 
-@interface CHIPViewControllerBase ()
+@interface CHIPViewControllerBase () <CHIPDeviceControllerDelegate>
 
 @property (readwrite) dispatch_queue_t chipCallbackQueue;
 @property (readwrite) BOOL reconnectOnForeground;
@@ -53,28 +53,9 @@ - (void)viewDidLoad
     [self.view addGestureRecognizer:tap];
 
     // initialize the device controller
-    __weak typeof(self) weakSelf = self;
     dispatch_queue_t callbackQueue = dispatch_queue_create("com.zigbee.chip.example.callback", DISPATCH_QUEUE_SERIAL);
     self.chipController = [CHIPDeviceController sharedController];
-    [self.chipController registerCallbacks:callbackQueue
-        onConnected:^(void) {
-            typeof(self) strongSelf = weakSelf;
-            [strongSelf postConnected];
-        }
-        onMessage:^(NSData * _Nonnull message) {
-            typeof(self) strongSelf = weakSelf;
-            if ([CHIPDeviceController isDataModelCommand:message] == YES) {
-                NSString * strMessage = [CHIPDeviceController commandToString:message];
-                [strongSelf postResult:strMessage];
-            } else {
-                NSString * strMessage = [[NSString alloc] initWithData:message encoding:NSUTF8StringEncoding];
-                [strongSelf postResult:strMessage];
-            }
-        }
-        onError:^(NSError * _Nonnull error) {
-            typeof(self) strongSelf = weakSelf;
-            [strongSelf postError:error.localizedDescription];
-        }];
+    [self.chipController setDelegate:self queue:callbackQueue];
 
     // need to restart connections on background/foreground transitions otherwise the socket can be closed without CHIP knowing
     // about it.
@@ -248,4 +229,30 @@ - (void)viewDidDisappear:(BOOL)animated
     }
 }
 
+#if 0
+#pragma mark -
+#pragma mark == CHIPDeviceControllerDelegate Methods ==
+#endif
+
+- (void)deviceControllerOnConnected
+{
+    [self postConnected];
+}
+
+- (void)deviceControllerOnMessage:(NSData *)message
+{
+    if ([CHIPDeviceController isDataModelCommand:message] == YES) {
+        NSString * strMessage = [CHIPDeviceController commandToString:message];
+        [self postResult:strMessage];
+    } else {
+        NSString * strMessage = [[NSString alloc] initWithData:message encoding:NSUTF8StringEncoding];
+        [self postResult:strMessage];
+    }
+}
+
+- (void)deviceControllerOnError:(NSError *)error
+{
+    [self postError:error.localizedDescription];
+}
+
 @end

src/darwin/Framework/CHIP/CHIPDeviceController.h

@@ -27,6 +27,8 @@ typedef void (^ControllerOnConnectedBlock)(void);
 typedef void (^ControllerOnMessageBlock)(NSData * message);
 typedef void (^ControllerOnErrorBlock)(NSError * error);
 
+@protocol CHIPDeviceControllerDelegate;
+
 @interface AddressInfo : NSObject
 
 @property (readonly, copy) NSString * ip;
@@ -69,20 +71,42 @@ typedef void (^ControllerOnErrorBlock)(NSError * error);
 + (CHIPDeviceController *)sharedController;
 
 /**
- * Register callbacks for network activity.
+ * Set the Delegate for the Device Controller as well as the Queue on which the Delegate callbacks will be triggered
+ *
+ * @param[in] delegate The delegate the Device Controller should use
+ *
+ * @param[in] queue The queue on which the Device Controller will deliver callbacks
+ */
+- (void)setDelegate:(id<CHIPDeviceControllerDelegate>)delegate queue:(dispatch_queue_t)queue;
+
+@end
+
+/**
+ * The protocol definition for the CHIPDeviceControllerDelegate
+ *
+ * All delegate methods will be called on the supplied Delegate Queue.
+ */
+@protocol CHIPDeviceControllerDelegate <NSObject>
+
+/**
+ * Notify the delegate when a connection request succeeds
  *
- * @param[in] appCallbackQueue the queue that should be used to deliver the
- *                             message/error callbacks for this consumer.
+ */
+- (void)deviceControllerOnConnected;
+
+/**
+ * Notify the delegate that a message was received
  *
- * @param[in] onMessage the block to call when the controller gets a message
- *                      from the network.
+ * @param[in] message The received message
+ */
+- (void)deviceControllerOnMessage:(NSData *)message;
+
+/**
+ * Notify the Delegate that an error occurred
  *
- * @param[in] onError the block to call when there is a network error.
+ * @param[in] error The error that occurred
  */
-- (void)registerCallbacks:(dispatch_queue_t)appCallbackQueue
-              onConnected:(ControllerOnConnectedBlock)onConnected
-                onMessage:(ControllerOnMessageBlock)onMessage
-                  onError:(ControllerOnErrorBlock)onError;
+- (void)deviceControllerOnError:(NSError *)error;
 
 @end
 

src/darwin/Framework/CHIP/CHIPDeviceController.mm

@@ -52,11 +52,16 @@ @interface CHIPDeviceController ()
 // queue used to call select on the system and inet layer fds., remove this with NW Framework.
 // primarily used to not block the work queue
 @property (atomic, readonly) dispatch_queue_t chipSelectQueue;
-// queue used to signal callbacks to the application
-@property (readwrite) dispatch_queue_t appCallbackQueue;
-@property (readwrite) ControllerOnConnectedBlock onConnectedHandler;
-@property (readwrite) ControllerOnMessageBlock onMessageHandler;
-@property (readwrite) ControllerOnErrorBlock onErrorHandler;
+/**
+ *  The Controller delegate.
+ *  Note: Getter is not thread safe.
+ */
+@property (readonly, weak, nonatomic) id<CHIPDeviceControllerDelegate> delegate;
+
+/**
+ * The delegate queue where delegate callbacks will run
+ */
+@property (readonly, nonatomic) dispatch_queue_t delegateQueue;
 @property (readonly) chip::DeviceController::ChipDeviceController * cppController;
 @property (readwrite) NSData * localKey;
 @property (readwrite) NSData * peerKey;
@@ -150,34 +155,37 @@ static void onInternalError(chip::DeviceController::ChipDeviceController * devic
 - (void)_dispatchAsyncErrorBlock:(NSError *)error
 {
     CHIP_LOG_METHOD_ENTRY();
-    // to avoid retaining "self"
-    ControllerOnErrorBlock onErrorHandler = self.onErrorHandler;
 
-    dispatch_async(_appCallbackQueue, ^() {
-        onErrorHandler(error);
-    });
+    id<CHIPDeviceControllerDelegate> strongDelegate = [self delegate];
+    if (strongDelegate && [self delegateQueue]) {
+        dispatch_async(self.delegateQueue, ^{
+            [strongDelegate deviceControllerOnError:error];
+        });
+    }
 }
 
 - (void)_dispatchAsyncMessageBlock:(NSData *)data
 {
     CHIP_LOG_METHOD_ENTRY();
-    // to avoid retaining "self"
-    ControllerOnMessageBlock onMessageHandler = self.onMessageHandler;
 
-    dispatch_async(_appCallbackQueue, ^() {
-        onMessageHandler(data);
-    });
+    id<CHIPDeviceControllerDelegate> strongDelegate = [self delegate];
+    if (strongDelegate && [self delegateQueue]) {
+        dispatch_async(self.delegateQueue, ^{
+            [strongDelegate deviceControllerOnMessage:data];
+        });
+    }
 }
 
 - (void)_dispatchAsyncConnectBlock
 {
     CHIP_LOG_METHOD_ENTRY();
-    // to avoid retaining "self"
-    ControllerOnConnectedBlock onConnectedHandler = self.onConnectedHandler;
 
-    dispatch_async(_appCallbackQueue, ^() {
-        onConnectedHandler();
-    });
+    id<CHIPDeviceControllerDelegate> strongDelegate = [self delegate];
+    if (strongDelegate && [self delegateQueue]) {
+        dispatch_async(self.delegateQueue, ^{
+            [strongDelegate deviceControllerOnConnected];
+        });
+    }
 }
 
 - (void)_manualKeyExchange:(chip::Transport::PeerConnectionState *)state
@@ -443,15 +451,17 @@ + (NSString *)commandToString:(NSData * _Nonnull)response
     return [NSString stringWithFormat:@"Sending '%@' command %@", command, status];
 }
 
-- (void)registerCallbacks:appCallbackQueue
-              onConnected:(ControllerOnConnectedBlock)onConnected
-                onMessage:(ControllerOnMessageBlock)onMessage
-                  onError:(ControllerOnErrorBlock)onError
+- (void)setDelegate:(id<CHIPDeviceControllerDelegate>)delegate queue:(dispatch_queue_t)queue
 {
-    self.appCallbackQueue = appCallbackQueue;
-    self.onConnectedHandler = onConnected;
-    self.onMessageHandler = onMessage;
-    self.onErrorHandler = onError;
+    [self.lock lock];
+    if (delegate && queue) {
+        self->_delegate = delegate;
+        self->_delegateQueue = queue;
+    } else {
+        self->_delegate = nil;
+        self->_delegateQueue = NULL;
+    }
+    [self.lock unlock];
 }
 
 @end