I’m writing unit tests that programatically start a name node and populate HDFS directories, but I want to simulate the situation where I don’t have read access to some HDFS directory (which happens on the real grid I eventually deploy to).
I’ve tried to chown and chmod, but it seems to have no effect, and my unit tests happily read the directory I don’t want them to be able to read. Looking at the permissions documentation, it seems that because my unit test program started the name node, it is automatically superuser. I tried setting dfs.permissions.supergroup to some other user, but that didn’t work either.
Is there any way I could have that unit test think it’s not the user who started the name node?