#if $__user_email__ == ""
<display>You are not authorized to use this tool</display>
#else
<command interpreter="python">
data_source.py $output $__app__.config.output_size_limit
</command>
To make this approach work, the email check should go in the command tag.
More information:
If you're looking to require users to login before using any tools, you can use this flag in the universe config file:
# Force everyone to log in (disable anonymous access).
#require_login = False
If you're looking to implement tool-based access control, the best approach is probably to use the same role-based approach that libraries use:
Thanks,
J.