get_temporary_link returns empty json string some times

I'm not aware of any issues that should currently be causing /2/files/get_temporary_link to return an empty string. Can you print out the full raw request and response (including headers and body for both) for a sample of that so we can take a look? Just be sure to redact the access token. Feel free to open an API ticket if you'd prefer to share privately.

The Dropbox API does have a rate limiting system, but any call that gets rate limited by the system would receive an error response with a relevant error status code and an error message in the response body. Make sure you're checking the status code and response body for errors, and don't have your code assume the response body will be JSON unless indicated as such by the response's Content-Type header.