[WebSocket] RCTWebSocket crashes when receiving messages in binary format

[orktes]

WebSocket client doesn't currently contain any handling for binary messages and just passes the message directly to bridge. This crashes the application.

*** Terminating app due to uncaught exception 'NSInvalidArgumentException', reason: 'Invalid type in JSON write (_NSInlineData)'

Problematic code:

react-native/Libraries/WebSocket/RCTWebSocketManager.m

Lines 83 to 89 in 0c9c6e8

	- (void)webSocket:(RCTSRWebSocket *)webSocket didReceiveMessage:(id)message
	{
	[_bridge.eventDispatcher sendDeviceEventWithName:@"websocketMessage" body:@{
	@"data": message,
	@"id": webSocket.reactTag
	}];
	}

Few ways to fix this.

1. Wait for [Bridge] Array Buffers / Typed Arrays for WebSockets, Ajax #1424
2. Pass error describing the issue instead of crashing
3. Convert NSData to string
4. Base64 encode NSData and convert to arraybuffer & blob in JS

Personally I'd prefer 4. as it brings the polyfill api more closer to actual WebSocket behaviour. I can take a stab at the problem once we've settled with the correct approach.

Thanks!

[orktes]

It seems that FileReader and atob (and probably Blob) are not implemented in JSCore by default. One option could be to decode base64 in pure JS directly into a TypedArray and then only support binaryType="text" and binaryType="arraybuffer".

master...Applifier:feature/ws_binaryType

[phoboslab]

We could also just push Apple to provide a native API for Typed Arrays in JSCore:
https://bugs.webkit.org/show_bug.cgi?id=120112

[brentvatne]

Hi there! This issue is being closed because it has been inactive for a while.

But don't worry, it will live on with ProductPains! Check out it's new home: https://productpains.com/post/react-native/websocket-rctwebsocket-crashes-when-receiving-messages-in-binary-format