NAME
Badger::Data::Facet - base class validation facet for simple data types
SYNOPSIS
TODO
PLEASE NOTE
This module is a work in progress. The implementation is subject to change and the documentation may be incomplete or incorrect in places.
DESCRIPTION
This module implements a base class validation facet for data types.
METHODS
init($config)
Custom initialisation method for data facets. Subclasses may redefine this method to do something different. Otherwise the default behaviour is as follows.
It first looks for any $ARGS package variables (in the current and any base classes) which denote the names of mandatory arguments for the data type.
our $ARGS = ['foo', 'bar'];It then asserts that each of these is defined in the $config and copies the value into $self.
Any optional parameters can be specified using the $OPTS package variable.
our $OPTS = 'baz'; # single string is sugar for ['baz']If any of these value(s) are defined in the $config then they will be copied into $self.
validate($value,$type)
This is the main validation method for facets. Subclasses must redefine this method to implement their own validation routine.
The first argument is a reference to the candidate value. For list and hash data types, this will be a reference to the list or hash respectively, as you would usually expect. If the value is a non-reference scalar (e.g. a number or text string) then a reference will also be passed. You may not be expecting this.
$facet->validate(\$text);
$facet->validate(\@list);
$facet->validate(\%hash);invalid($message)
This method is used internally (e.g. by the validate() method) to report invalid values.
$self->invalid("The value specified is not valid");invalid_msg($format,@args)
This method is used internally (e.g. by the validate() method) to report invalid values using a pre-defined message() format.
our $MESSAGES = {
not_orange => 'The colour specified is not orange: %s',
};
sub validate {
my ($self, $value) = @_;
return $$value eq 'orange'
|| $self->invalid_msg( not_orange => $$value );
}PACKAGE VARIABLES
$MESSAGES
Subclasses may defined their own message formats (for use with invalid_msg()) using the $MESSAGES package variable. This should be a reference to a hash array mapping short names to message formats. These formats are expanded using the xprintf()|Badger::Utils/xprintf() function in Badger::Utils. This is a wrapper around sprintf() with some extra syntactic sugar for handling positional arguments.
our $MESSAGES = {
# messages taking one and two parameters
not_orange => 'The colour specified is not orange: %s',
not_colour => 'The colour specified is not %s: %s',
# message specifying parameters in a different order
alt_colour => 'You specified the colour <2> but that is not <1>.',
};AUTHOR
Andy Wardley http://wardley.org/
COPYRIGHT
Copyright (C) 2001-2009 Andy Wardley. All Rights Reserved.
This module is free software; you can redistribute it and/or modify it under the same terms as Perl itself.
ACKNOWLEDGEMENTS
This module is derived from the XML::Schema::Facet module, also written by Andy Wardley under funding from Canon Research Europe Ltd.