LabVIEW™ Web Service Streaming Fails After a Certain Number of Requests

Issue Details

I created a LabVIEW™ Web Service but the streaming code fails consistently after a certain number of requests regardless of browser or operating system, without throwing any error message on the client.

Solution

This is an issue that can happen while continuously calling the Create Session and Destroy Session VIs for each request, causing the browser to accumulate session cookies to a point that it reaches a maximum header size limit.

We can see this process as:

1. Create session.
2. Get information.
3. Send HTTP response.
4. Destroy session.

Since the acquisition is continuous, it's not optimal to be constantly opening and closing sessions, so it would be better to just keep one session for this and just keep reusing it to reduce the server-side overheard and resources. Considering that, we can fix this by modifying the process as follows:

1. Check if there's an open session (with Check If Session Exists VI).
2. Create session if there wasn't one already.
3. Get information.
4. Send HTTP response.