Merge pull request #43 from hummingbird-project/ignore-close-errors

Don't error on writing close frame after receiving close frame

Author: Joannis

Sources/WSCore/WebSocketHandler.swift

@@ -194,7 +194,7 @@ public struct WebSocketCloseFrame: Sendable {
                         // Close handshake. Wait for responding close or until inbound ends
                         while let frame = try await inboundIterator.next() {
                             if case .connectionClose = frame.opcode {
-                                try await self.receivedClose(frame)
+                                await self.receivedClose(frame)
                                 // only the server can close the connection, so clients
                                 // should continue reading from inbound until it is closed
                                 if type == .server {
@@ -319,14 +319,16 @@ public struct WebSocketCloseFrame: Sendable {
         }
     }
 
-    func receivedClose(_ frame: WebSocketFrame) async throws {
+    func receivedClose(_ frame: WebSocketFrame) async {
         guard frame.reservedBits.isEmpty else {
-            try await self.close(code: .protocolError, reason: nil)
+            // ignore errors from sending close as the other side may have closed the connection already
+            try? await self.close(code: .protocolError, reason: nil)
             return
         }
         switch self.stateMachine.receivedClose(frameData: frame.unmaskedData, validateUTF8: self.configuration.validateUTF8) {
         case .sendClose(let errorCode):
-            try await self.sendClose(code: errorCode, reason: nil)
+            // ignore errors from sending close as the other side may have closed the connection already
+            try? await self.sendClose(code: errorCode, reason: nil)
             // Only server should initiate a connection close. Clients should wait for the
             // server to close the connection when it receives the WebSocket close packet
             // See https://www.rfc-editor.org/rfc/rfc6455#section-7.1.1

Sources/WSCore/WebSocketInboundStream.swift

@@ -54,7 +54,7 @@ public final class WebSocketInboundStream: AsyncSequence, Sendable {
                     self.handler.logger.trace("Received \(frame.traceDescription)")
                     switch frame.opcode {
                     case .connectionClose:
-                        try await self.handler.receivedClose(frame)
+                        await self.handler.receivedClose(frame)
                         return nil
                     case .ping:
                         try await self.handler.onPing(frame)