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package Error::Helper;
use strict;
=head1 NAME
Error::Helper - Provides some easy error related methods.
=head1 VERSION
Version 2.1.0
=cut
our $VERSION = '2.1.0';
our $error = undef;
our $perror = undef;
our $errorLine = undef;
our $errorFilename = undef;
our $errorString = '';
our $errorFlag = undef;
our $errorPackage = undef;
our $errorPackageShort = undef;
our $errorSub = undef;
our $errorSubShort = undef;
=head1 SYNOPSIS
Below is a example script showing it's usage.
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',
4 => 'test2',
},
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;
}
# error if $arg is set to "test2", error fatally
if ( defined($arg)
&& $arg eq "test" )
{
$self->{perror} = 1;
$self->{error} = 4;
$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;
}
# this will be fatal as it error flag derp is set to fatal
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;
eval {
$foo_obj = Foo->new( $ARGV[0] );
# will never be evaulated as perrors are fatal
if ( $foo_obj->error ) {
warn( 'error:' . $foo_obj->error . ': ' . $foo_obj->errorString );
exit $foo_obj->error;
}
};
if ($@) {
print 'Error: ' . $Error::Helper::error .
"\nError String: " . $Error::Helper::errorString .
"\nError Flag: " . $Error::Helper::errorFlag .
"\nError File: " . $Error::Helper::errorFilename .
"\nError Line: " . $Error::Helper::errorLine .
"\nError Sub: " . $Error::Helper::errorSub .
"\nError Sub Short: " . $Error::Helper::errorSubShort .
"\nError Package: " . $Error::Helper::errorPackage .
"\nError PackageShort: " . $Error::Helper::errorPackageShort . "\n";
exit $Error::Helper::error;
}
# catches fatal errors
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...
warn( '$foo_obj->foo( $ARGV[1] ) errored');
}
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
This module also sets several other variables as well for when something like a new method is called
and dies, before something blessed can be returned. These allow examining the the error that resulted in it dieing.
The following are mapped to the the ones above.
$Error::Helper::perror
$Error::Helper::error
$Error::Helper::errorString
$Error::Helper::errorFlag
$Error::Helper::errorFilename
$Error::Helper::errorLine
The following don't have mappings above.
- $Error::Helper::errorSub :: The sub that warn was called from.
- $Error::Helper::errorSubShort :: Same as errorSub, but everything prior to the subname is
removed. So Foo::bar would become bar.
- $Error::Helper::errorPackage :: The package from which warn was called from.
- $Error::Helper::errorPackageShort :: Saome as package, but everthing prior to the last item
in the name space is removed. So Foo::Foo::Bar would just become Bar.
=head1 METHODS
=head2 error
Returns the current error code and true if there is an error.
If there is no error, undef is returned.
if($self->error){
# do something
}
=cut
sub error {
return $_[0]->{error};
}
=head2 errorblank
This blanks the error storage and is only meant for internal usage.
It does the following.
$self->{error} = undef;
$self->{errorFilename} = undef;
$self->{errorLine} = undef;
$self->{errorString} = "";
If $self->{perror} is set, it will not be able to blank any current
errors.
=cut
sub errorblank {
my $self = $_[0];
if ( $self->{perror} ) {
my ( $package, $filename, $line ) = caller;
#get the calling sub
my @called = caller(1);
my $subroutine = $called[3];
$subroutine =~ s/.*\:\://g;
$package =~ s/\:\:/\-/g;
my $error
= $package . ' '
. $subroutine
. ': Unable to blank, as a permanent error is set. '
. 'error="'
. $self->error
. '" errorFilename="'
. $self->errorFilename
. '" errorLine="'
. $self->errorLine
. '" errorString="'
. $self->errorString
. '" file="'
. $filename
. ' line='
. $line;
if ( !$self->{errorExtra}{perror_not_fatal} ) {
die($error);
} else {
print STDERR $error;
}
return undef;
} ## end if ( $self->{perror} )
$self->{error} = undef;
$self->{errorFilename} = undef;
$self->{errorLine} = undef;
$self->{errorString} = "";
$error = undef;
$perror = undef;
$errorLine = undef;
$errorFilename = undef;
$errorString = '';
$errorFlag = undef;
$errorPackage = undef;
$errorPackageShort = undef;
$errorSub = undef;
$errorSubShort = undef;
return 1;
} ## end sub errorblank
=head2 errorFilename
This returns the filename in which the error occured or other wise returns undef.
if($self->error){
print 'error happened in '.$self->errorFilename."\n";
}
=cut
sub errorFilename {
return $_[0]->{errorFilename};
}
=head2 errorFlag
This returns the error flag for the current error.
If none is set, undef is returned.
This may be used in a similar manner as the error method.
if ( $self->errorFlag ){
if ( $self->errorFlag eq 'foo' ){
# do something
}else{
die('error flag '.$self->errorFlag.' can not be handled');
}
}
=cut
sub errorFlag {
if ( !$_[0]->{error} ) {
return undef;
}
if ( !defined( $_[0]->{errorExtra} )
|| ref( $_[0]->{errorExtra} ) ne 'HASH'
|| ( !defined( $_[0]->{errorExtra}{flags} ) )
|| ref( $_[0]->{errorExtra}{flags} ) ne 'HASH'
|| !defined( $_[0]->{errorExtra}{flags}{ $_[0]->{error} } ) )
{
return 'other';
}
return $_[0]->{errorExtra}{flags}{ $_[0]->{error} };
} ## end sub errorFlag
=head2 errorLine
This returns the filename in which the error occured or other wise returns undef.
if($self->error){
print 'error happened at line '.$self->errorLine."\n";
}
=cut
sub errorLine {
return $_[0]->{errorLine};
}
=head2 errorString
Returns the error string if there is one. If there is not,
it will return ''.
if($self->error){
warn('error: '.$self->error.":".$self->errorString);
}
=cut
sub errorString {
return $_[0]->{errorString};
}
=head2 perror
This returns a Perl boolean for if there is a permanent
error or not.
if($self->perror){
warn('A permanent error is set');
}
=cut
sub perror {
return $_[0]->{perror};
}
=head2 warn
Throws a warn like error message based using the contents of $self->errorString
$self->warn;
=cut
sub warn {
my $self = $_[0];
my ( $package, $filename, $line ) = caller;
$errorPackage = $package;
$self->{errorFilename} = $filename;
$errorFilename = $filename;
$self->{errorLine} = $line;
$errorLine = $line;
if ( !defined( $self->{error} ) ) {
$self->{error} = 3060;
}
$error = $self->{error};
if ( !defined( $self->{errorString} ) ) {
$self->{errorString} = 'unknown... warn called without errorString being set';
}
$errorString = $self->{errorString};
$perror = $self->{perror};
$errorFlag = $self->errorFlag;
#get the calling sub
my @called = caller(1);
my $subroutine = $called[3];
$errorSub = $subroutine;
$subroutine =~ s/.*\:\://g;
$errorSubShort = $subroutine;
$package =~ s/\:\:/\-/g;
$errorPackageShort = $package;
my $error
= $package . ' '
. $subroutine . ':'
. $self->error . ':'
. $errorFlag . ': '
. $errorString
. ' at line '
. $line . ' in '
. $filename . "\n";
if (
$self->{errorExtra}{all_fatal}
|| (
$self->perror
&& !(
defined( $self->{errorExtra} )
&& ref( $self->{errorExtra} ) eq 'HASH'
&& $self->{errorExtra}{perror_not_fatal}
)
)
|| ( defined( $self->{errorExtra} )
&& ref( $self->{errorExtra} ) eq 'HASH'
&& defined( $self->{errorExtra}{fatal_errors} )
&& ref( $self->{errorExtra}{fatal_errors} ) eq 'HASH'
&& $self->{errorExtra}{fatal_errors}{ $self->{error} } )
|| ( defined( $self->{errorExtra} )
&& ref( $self->{errorExtra} ) eq 'HASH'
&& defined( $self->{errorExtra}{fatal_flags} )
&& ref( $self->{errorExtra}{fatal_flags} ) eq 'HASH'
&& $self->{errorExtra}{fatal_flags}{ $self->errorFlag } )
)
{
die($error);
} ## end if ( $self->{errorExtra}{all_fatal} || ( $self...))
print STDERR $error;
} ## end sub warn
=head2 warnString
Throws a warn like error in the same for mate as warn, but with a freeform message.
This will not trigger any of the fatality checks. It will also not set any of the error values.
$self->warnString('some error');
=cut
sub warnString {
my $self = $_[0];
my $string = $_[1];
if ( !defined($string) ) {
$string = 'undef';
}
my ( $package, $filename, $line ) = caller;
#get the calling sub
my @called = caller(1);
my $subroutine = $called[3];
if ( defined($subroutine) ) {
$subroutine =~ s/.*\:\://g;
$package =~ s/\:\:/\-/g;
print STDERR $package . ' ' . $subroutine . ': ' . $string . ' in ' . $filename . ' at line ' . $line . "\n";
} else {
print STDERR $package . ': ' . $string . ' in ' . $filename . ' at line ' . $line . "\n";
}
} ## end sub warnString
=head1 ERROR FLAGS
Error flags are meant to be short non-spaced strings that are easier to remember than a specific error integer.
'other' is the generic error flag for when one is not defined.
An error flag should never evaluate to false if an error is present.
=head1 AUTHOR
Zane C. Bowers-Hadley, C<< <vvelox at vvelox.net> >>
=head1 BUGS
Please report any bugs or feature requests to C<bug-error-helper at rt.cpan.org>, or through
the web interface at L<http://rt.cpan.org/NoAuth/ReportBug.html?Queue=Error-Helper>. I will be notified, and then you'll
automatically be notified of progress on your bug as I make changes.
=head1 SUPPORT
You can find documentation for this module with the perldoc command.
perldoc Error::Helper
You can also look for information at:
=over 4
=item * RT: CPAN's request tracker
=item * Search CPAN
=back
=head1 LICENSE AND COPYRIGHT
Copyright 2023 Zane C. Bowers-Hadley.
This program is free software; you can redistribute it and/or modify it
under the terms of either: the GNU General Public License as published
by the Free Software Foundation; or the Artistic License.
See http://dev.perl.org/licenses/ for more information.
=cut
1; # End of Error::Helper