Eliminate RCTWebSocketManager

Summary: This singleton was unnecessary and can be implemented with a single `static` in `RCTDevMenu`. In another diff, I will rename `RCTWebSocketManager.{h,m}` to reflect the only class that remains.

Reviewed By: javache

Differential Revision: D4296551

fbshipit-source-id: 653971dfb31de5b0a161b531eed82a067f536ce3

Libraries/WebSocket/RCTWebSocketManager.h

@@ -15,7 +15,4 @@
 @interface RCTWebSocketObserver : NSObject <RCTWebSocketObserver>
 @end
 
-@interface RCTWebSocketManager : NSObject <RCTWebSocketProxy>
-@end
-
 #endif

Libraries/WebSocket/RCTWebSocketManager.m

@@ -18,8 +18,6 @@
 
 #if RCT_DEV // Only supported in dev mode
 
-#pragma mark - RCTWebSocketObserver
-
 @interface RCTWebSocketObserver () <RCTSRWebSocketDelegate>
 @end
 
@@ -91,56 +89,4 @@ - (void)webSocket:(RCTSRWebSocket *)webSocket didCloseWithCode:(NSInteger)code r
 
 @end
 
-#pragma mark - RCTWebSocketManager
-
-@interface RCTWebSocketManager()
-
-@property (nonatomic, strong) NSMutableDictionary *sockets;
-
-@end
-
-@implementation RCTWebSocketManager
-
-+ (instancetype)sharedInstance
-{
-  static RCTWebSocketManager *sharedInstance = nil;
-  static dispatch_once_t onceToken;
-
-  dispatch_once(&onceToken, ^{
-    sharedInstance = [self new];
-  });
-
-  return sharedInstance;
-}
-
-- (void)setDelegate:(id<RCTWebSocketProxyDelegate>)delegate forURL:(NSURL *)url
-{
-  NSString *key = [url absoluteString];
-  RCTWebSocketObserver *observer = _sockets[key];
-
-  if (observer) {
-    if (!delegate) {
-      [observer stop];
-      [_sockets removeObjectForKey:key];
-    } else {
-      observer.delegate = delegate;
-    }
-  } else {
-    RCTWebSocketObserver *newObserver = [[RCTWebSocketObserver alloc] initWithURL:url];
-    newObserver.delegate = delegate;
-    [newObserver start];
-    _sockets[key] = newObserver;
-  }
-}
-
-- (instancetype)init
-{
-  if ((self = [super init])) {
-    _sockets = [NSMutableDictionary new];
-  }
-  return self;
-}
-
-@end
-
 #endif

React/Base/RCTWebSocketProxy.h

@@ -17,6 +17,7 @@
 @protocol RCTWebSocketObserver
 - (instancetype)initWithURL:(NSURL *)url;
 @property (nonatomic, weak) id<RCTWebSocketProxyDelegate> delegate;
+- (void)start;
 @end
 
 @protocol RCTWebSocketProxy

React/Modules/RCTDevMenu.m

@@ -267,14 +267,39 @@ - (NSURL *)packagerURL
 // TODO: Move non-UI logic into separate RCTDevSettings module
 - (void)connectPackager
 {
-  Class webSocketManagerClass = objc_lookUpClass("RCTWebSocketManager");
-  id<RCTWebSocketProxy> webSocketManager = (id <RCTWebSocketProxy>)[webSocketManagerClass sharedInstance];
+  RCTAssertMainQueue();
+
   NSURL *url = [self packagerURL];
-  if (url) {
-    [webSocketManager setDelegate:self forURL:url];
+  if (!url) {
+    return;
+  }
+
+  Class webSocketObserverClass = objc_lookUpClass("RCTWebSocketObserver");
+  if (webSocketObserverClass == Nil) {
+    return;
+  }
+
+  // If multiple RCTDevMenus are created, the most recently connected one steals the RCTWebSocketObserver.
+  // (Why this behavior exists is beyond me, as of this writing.)
+  static NSMutableDictionary<NSString *, id<RCTWebSocketObserver>> *observers = nil;
+  if (observers == nil) {
+    observers = [NSMutableDictionary new];
+  }
+
+  NSString *key = [url absoluteString];
+  id<RCTWebSocketObserver> existingObserver = observers[key];
+  if (existingObserver) {
+    existingObserver.delegate = self;
+  } else {
+    id<RCTWebSocketObserver> newObserver = [(id<RCTWebSocketObserver>)[webSocketObserverClass alloc] initWithURL:url];
+    newObserver.delegate = self;
+    [newObserver start];
+    observers[key] = newObserver;
   }
 }
 
+
+
 - (BOOL)isSupportedVersion:(NSNumber *)version
 {
   NSArray<NSNumber *> *const kSupportedVersions = @[ @1 ];