Http request timeout crashes

Development Programming & Scripting
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1

Hello, I have a simple Async blueprint node written in c++ that does some http requests every 0.5s to a local server and then calls a MULTICAST_DELEGATE callback.

If the server I’m trying to ping is offline, or takes more time to respond then the interval I’m calling the HTTP request ( say the interval is 0.5s, and the server responds or the timeout is in 1.0s ) I get a crash after a couple of runs.

I imagine it has something to do with the fact that the mRequest->OnProcessRequestComplete().BindLambda takes a time to run and the Delegate doesn’t exists anymore.

here’s my code:

	TSharedPtr<IHttpRequest, ESPMode::ThreadSafe> mRequest  = FHttpModule::Get().CreateRequest().ToSharedPtr();
	mRequest->SetVerb(mVerb);
	mRequest->SetTimeout(0.4f); // if this is more then the interval you are calling this function, you will get a crash
	mRequest->SetHeader("Content-Type", "application/json");
	mRequest->SetURL(mUrl);

	mRequest->OnProcessRequestComplete().BindLambda([this, startMs, mRequest](FHttpRequestPtr requestPtr, FHttpResponsePtr responsePtr, bool success) {
		FString ResponseString = "";
		if (success)
		{
			ResponseString = responsePtr->GetContentAsString();
		}

		CompletedCallback.Broadcast(ResponseString, success);
	});

	bool result = mRequest->ProcessRequest();
}

the crash happens inside MTAccessDetector.h in this line

ensureMsgf(ReaderIndex != INDEX_NONE, 
				TEXT("Either a race detected (%u reader(s) on another thread(s) while acquiring write access on the current thread) or the access detector was trivially relocated:\nCurrent thread %u callstack:\n%s"), 
				LocalState.ReaderNum, FPlatformTLS::GetCurrentThreadId(), *GetCurrentThreadCallstack());

is there a way to know if the CompletedCallback is still valid?