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kotlinlang

I'd add, because CSV's can be tricky (embedded ""'s for example).  I'd use the fasterxml.jackson or openCSV libraries to create the CSV and then download that to the client browser.  One can also set the Content-Type header to a value (application/excel as I recall) to have the browser open it in MS Excel (or similar)

Thanks Alex. Yes, I know CSV can be messy. But I have good control of the data and know what characters I can expect. And, I do not really want to make any changes to the server side at this time, prefer to have a client-only solution creating the file.