On 16 Sep 2002 at 18:10, Perrin Harkins wrote: > The way that most people would recommend in A::R or anything else is to > trap errors with eval blocks and then handle them appropriately.
I thought I was doing that at a global level by throwing an error with die() that was caught by CGI::Carp. I'm realizing that it isn't so simple. > > Unfortunately, CGI::Carp is still not displaying my custom error message > > which I set in a BEGIN block using the set_message() function. > > I don't know a lot about CGI::Carp specifically, but I'm guessing it > tries to avoid catching any dies inside of evals, so you will probably have > to modify it or roll your own if you want that behavior. Ahhh, that makes sense. Of course, my application still stops executing, but I guess that is because the error percolated up to mod_perl then back down to CGI::Carp which had set the %SIG hash. > > I guess this system wouldn't work if I try to > > redefine the set_message function in other Registry scripts since > > CGI::Carp is not being instantiated individually in each script (or is > > it??). > > If it uses globals (as opposed to an OO interface) then it's the same > globals for every Registry script. That would be a problem if you only set > it in the BEGIN block, but you could easilly set it on every execution of > the script. Ohh, well isn't that a good idea ;-p. I feel like a beginner all over again in this environment. > If you leave $@ set, it will cause A::R to return a SERVER_ERROR status and > apache will send a generic error page after your message. Oh, so if I handle the error myself, I should unset $@? I didn't see this in the example mydie function in the Guide. However, exit 1 is called at the end of the subroutine which may be sufficient for bypassing the A::R check. > You can override die, or install a signal handler for the DIE hook, or wrap > your code in an eval block. One of the the members of the CGI::Application mailing list suggested using Graham Barr's Error module and a wrap around the instantiation script. It's an interesting approach which I'm going to take a look at today. > > Indeed, it appears that the suggestion in the Code Snippets section of > > the mod_perl guide > > <http://perl.apache.org/docs/1.0/guide/snippets.html#Redirecting_Errors_t > > o_ the_Client_Instead_of_error_log> will not work as given for > > Apache::Registry scripts. > > It should work. The signal handler is called even inside an eval. Hmm, I'll try again. I still am having no luck. I've walked through the execution with the debugger and am finding that Carp::longmess_heavy is catching my die() calls despite the fact that I have set `local $SIG{__DIE__} = \&mydie;`. I was using the diagnostics and warnings pragmas but turned them off (diagnostics was catching the die before Carp). However, I'm not using Carp... except in my startup.pl that I copied from somewhere on the net: `$SIG{__WARN__} = \&Carp::cluck;` I removed that code but am still getting Carp being called before my custom handler. It must be some library I'm using but why wouldn't my localized %SIG override this value? Very confused, William -- Lead Developer Knowmad Services Inc. || Internet Applications & Database Integration http://www.knowmad.com
