Thread Or Queue What to use?

Hi,

I have a web application which generates a report when a user clicks the button in an asynchronous manner. This operation might take some time and I was wondering how to handle this. I want to put the requests in queue and process them one by one and send an email to user when the report is generated to notify them. What is the suggested method? The user might hit the button and then logout so the process needs to run in the background.

Thanks
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