To protect against CSRF attacks,
HADOOP-12691 introduces a CSRF filter that will require a specific HTTP header to be sent with every REST API call. This will affect all API consumers from web apps to CLIs and curl.
Since CSRF is primarily a browser based attack we can try and minimize the impact on non-browser clients.
This enhancement will provide additional configuration for identifying non-browser useragents and skipping the enforcement of the header requirement for anything identified as a non-browser. This will largely limit the impact to browser based PUT and POST calls when configured appropriately.