Using HTTPS (SSL/TLS) for API Calls
As a security measure, you should make API calls to Tableau Server using the HTTPS protocol (SSL or TLS)—that is, using an encrypted channel between your client and Tableau Server. Information is passed as plaintext between the client and server using XML or JSON blocks in the request and response body. Using HTTPS protocol helps keep this information secure.
To make API calls with HTTPS, you must configure Tableau Server to use SSL. For details, see SSL(Link opens in a new window) in the Tableau Server documentation. (If you are testing Tableau Server, you can install a self-signed certificate in order to support SSL.) If you make an HTTPS call to Tableau Server but you have not configured the server to use SSL, the server refuses the request.
When working with Tableau Online, you must use the HTTPS protocol to make API calls.