/Error-Helper

Provides some handy error related methods

Primary LanguagePerlOtherNOASSERTION

Error::Helper Synopsis

This module allows one to use it as a base for adding various error handling methods to their module. Error checking can be done in two methods, either calling one of error checking functions and seeing if it is present or setting that error code/flag to be fatal and collecting failures via eval and then when processing $@, then check the error code/flag.

There are five required variables in the blessed hash object.

  • $self->{error} :: This contains the current error code.

    • Type :: int or undef
  • $self->{errorFilename} :: File from which $self->warn was called.

    • Type :: string or undef
  • $self->{errorLine} :: Line from which $self->warn was called.

    • Type :: int or undef
  • $self->{errorString} :: This contains a description of the current error.

    • Type :: string or undef
  • $self->{perror} :: This is set to true is a permanent error is present. If note, it needs set to false.

    • Type :: Perl boolean

The following are optional.

  • $self->{errorExtra} :: This is a hash reserved for any additional Error::Helper items.

  • $self->{errorExtra}{all_errors_fatal} :: If true, this will die when $self->warn is called instead of printing the error to STDERR. This is for if you want to use it eval for capturing errors and this module more for handling grabbing error specifics, such as dieing and additional code based on the return of $self->errorFlag. - Type :: Perl boolean - Default :: undef

  • $self->{errorExtra}{fatal_errors} :: This is a hash in which the keys are errors codes that are fatal. When $self->warn is called it will check if the error code is fatal or not. $self->{errorExtra}{fatal_errors}{33}=>1 would be fatal, but $self->{errorExtra}{fatal_errors}{33}=>0 would now.

  • $self->{errorExtra}{flags} :: This hash contains error integer to flag mapping. The keys are the error integer and the value is the flag. For any unmatched error integers, 'other' is returned.

  • $self->{errorExtra}{fatal_flags} :: This is a hash in which the keys are error flags that are fatal. When $self->warn is called it will check if the flag for the error code is fatal or not. For the flag foo $self->{errorExtra}{fatal_flags}{foo}=>1 would be fatal, but $self->{errorExtra}{fatal_flags}{foo}=>0 would now.

  • $self->{errorExtra}{perror_not_fatal} :: Controls if $self->{perror} is fatal or not.

    • Type :: Perl boolean
    • Default :: undef

Below is a example script showing it all being used.

#!/usr/bin/env perl
use warnings;
use strict;

{
	package Foo;
	use base 'Error::Helper';

	sub new {
		my $arg = $_[1];

		my $self = {
			perror        => undef,
			error         => undef,
			errorLine     => undef,
			errorFilename => undef,
			errorString   => "",
			errorExtra    => {
				all_errors_fatal => 0,
				flags            => {
					1 => 'UndefArg',
					2 => 'test',
					3 => 'derp',
				},
				fatal_flags => {
					derp => 1,
				},
				perror_not_fatal => 0,
			},
		};
		bless $self;

		#error if $arg is set to "test"
		if ( defined($arg)
			&& $arg eq "test" )
		{
			$self->{perror}      = 1;
			$self->{error}       = 2;
			$self->{errorString} = 'A value of "test" has been set';
			$self->warn;
			return $self;
		}

		return $self;
	} ## end sub new

	sub foo {
		my $self = $_[0];
		my $a    = $_[1];

		if ( !$self->errorblank ) {
			return undef;
		}

		if ( !defined($a) ) {
			$self->{error}       = 1;
			$self->{errorString} = 'No value specified';
			$self->warn;
			return undef;
		}

		if ( $a eq 'derp' ) {
			$self->{error}       = 3;
			$self->{errorString} = 'foo was called with a value of derp';
			$self->warn;
		}

		return 1;
	} ## end sub foo
}

my $foo_obj = Foo->new( $ARGV[0] );
if ( $foo_obj->error ) {
	warn( 'error:' . $foo_obj->error . ': ' . $foo_obj->errorString );
	exit $foo_obj->error;
}

eval { $foo_obj->foo( $ARGV[1] ); };
if ($@) {
	# do something...
	warn( '$foo_obj->foo( $ARGV[1] ) errored.... ' . $@ );
	if ( $foo_obj->errorFlag eq 'derp' ) {
		warn('error flag derp found... calling again with a value of default');
		$foo_obj->foo('default');
	}
} elsif ( $foo_obj->error ) {
	# do something...
	$foo_obj->warnString('non-fatal error when calling foo');
}