[rt-users] R: R: Custom authentication script fails with > ExternalAuthPriority not defined, please check your configuration file

[Thomas Sibley]

On 01/01/2013 10:43 AM, Scotto Alberto wrote:
> Don't know what is the best. I think using preconditions is a strong
> practice that gives you freedom and lets you avoid duplicate checks.
> Actually, the preconditions must be documented...
> 
> So I think that I may go for documenting the precondition in the wiki
> page (also for simplicity).
> 
> What do you think?

Relying on the input being validated before handed to the function is
asking for trouble as soon as the function starts being used in multiple
places, some of which may not validate the input.  The function should
be a black box, and you shouldn't need to know that it's going to pass
provided arguments to shell_exec().  Fix problems at the source, not at
some more distant location.  You'll end up playing whack a mole otherwise.

Thomas