Ensure SendCompletedAsync is called only once (#1210)

Shane32 · web-flow · commit 04bee453a9f6 · 2026-04-11T22:02:13.000Z
diff --git a/src/Transports.AspNetCore/WebSockets/BaseSubscriptionServer.Observer.cs b/src/Transports.AspNetCore/WebSockets/BaseSubscriptionServer.Observer.cs
@@ -73,6 +73,8 @@ public async void OnNext(ExecutionResult value)
                 await _server.SendDataAsync(_id, value);
                 if (_closeAfterAnyError && value.Errors?.Count > 0)
                 {
+                    if (Interlocked.Exchange(ref _done, 1) == 1)
+                        return;
                     await _server.SendCompletedAsync(_id);
                 }
             }

Original file line number	Diff line number	Diff line change
`@@ -73,6 +73,8 @@ public async void OnNext(ExecutionResult value)`
`73`	`73`	`await _server.SendDataAsync(_id, value);`
`74`	`74`	`if (_closeAfterAnyError && value.Errors?.Count > 0)`
`75`	`75`	`{`
	`76`	`+ if (Interlocked.Exchange(ref _done, 1) == 1)`
	`77`	`+ return;`
`76`	`78`	`await _server.SendCompletedAsync(_id);`
`77`	`79`	`}`
`78`	`80`	`}`