Hello fellow Perlmonks,

today I am asking for your wisdom in regards to best practices for error reporting in modules. I still would consider myself a novice, so this question may sound foolish to some.

So consider I want to write some kind of Module, currently I am working on one that internally deals with LDAP. The program using the module wants to know, if in a method call to the module something went wrong, e.g. the LDAP-connection timed out or something like this. There I somehow need to report errors happening to my module.

I see multiple ways of tackeling this and I am not content with either of them:

Option 1: report it with Log4Perl
All my programs write logs with Log4Perl anyway. So when my Module encounters an error, I report the Error-Message with Log4Perl and return 1 indicating an error.

Pro: Easy to do, Error easily found in log, not much clutter in my code
Cons: This is not very portable. Someone not using Log4Perl would not be able to use my module.

Option 2: internal error reporting in a moose errors accessor
I tend to write OO-Modules with Moose or Mouse. The module gets an accessor called "errors" like this:
has "errors" => (
is => rw,
isa => "Str",
predicate => "has_errors",
reader => "get_errors",
writer => "set_errors",
clearer => "clear_errors",
);

[download]
Every public method first calls 
 $self->clear_errors();
, then executes its functionality. Everytime an error occurs I can perform a 
 $self->set_errors($self->get_errors . $error_message);
and stash my errors this way. In the program using the module I can perform a 
 $module->get_errors
to retrieve the error-messages and a 
 $module->has_errors
to see if something went wrong.

Pro: Independent from Log4Perl!
Cons: Every Module of mine now has an errors accessor and some helperfunctions to add to this accessor, violating the DRY-principle. Also, not applicable if a method in the module itself, calls another function, as this would erase the errors-accessor. Obviously, doesn't work that great with non-OO modules

Option 3: Return an Error-Code
If everything goes right in a function, return 0. If something fails, return 1 or any higher number.

Pro: No hassle with overwriting error-accessors. I tend to use this for internal module-methods in mix with Option 2.
Cons: A lot! No proper error-message of what went wrong. If the method does return something (e.g. an LDAP-Object) this breaks and burns gloriously.

Currently I tend to use a mix of all these options and I do not like it. Option 2 makes me write a lot of similar code again and again, Option 1 makes me dependend on Log4Perl and Option 3 just doesn't work if the method returns something useful.

CPAN-Authors and Error-Catching-Perfectionists! How do you solve these problems? Proper error-catching is a very important duty in my coding environment as there services I have to work with tend to break a lot or are just not reliable and run a lot into timeouts.

I would love to hear some best practices and further options for dealing with this!

Greetings,
Yulivee

In reply to Best practices for module error-reporting by yulivee07

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