Validation of HTML Form Arrays using Data::FormValidator - forms

Question

Salutations!
I come to you with a little bit of an issue I'm experiencing with using Data::FormValidator at the moment. I will start with the code that I am currently working with; this is the template file I use to generate the form:
<form method="post" target="/">
text[] <input type="text" name="text[]" /><br />
text[] <input type="text" name="text[]" /><br />
text[] <input type="text" name="text[]" /><br />
text[] <input type="text" name="text[]" /><br />
<br />
abc <input type="radio" name="abc" value="1" /><br />
abc <input type="radio" name="abc" value="2" /><br />
abc <input type="radio" name="abc" value="3" /><br />
abc <input type="radio" name="abc" value="4" /><br />
abc <input type="radio" name="abc" value="5" /><br />
<br />
herp <input type="checkbox" name="herp" value="abc"><br />
dee <input type="checkbox" name="dee" value="dd"><br />
derp <input type="checkbox" name="derp" value="beri"><br />
<br />
<input type="submit" value="Submit!!!!" name="submit" /><br />
</form>
and this is the current code I'm using to test the array validation issues:
#!/usr/bin/env perl
use Carp;
use Data::Dumper;
use Template;
use Data::FormValidator;
use Data::FormValidator::Constraints qw(:closures);
use Dancer;
set logger => "file";
setting log_path => "./";
get '/' => sub {
template 'index.tt';
};
post '/' => sub {
my $self = shift;
my $par = params;
print Dumper($par);
my $profile = {
required => [ qw( text[] ) ],
optional => [ qw( abc herp dee derp ) ],
constraint_methods => {
'text[]' => sub {
my $self = shift;
my $val = shift;
print "Hello world. I'm validating text[], value = $val\n";
my $ret;
if($val =~ /^a/i) {
$ret = 1;
} else {
$ret = 0;
}
print "And I got: $ret\n";
return $ret;
},
},
};
print Dumper(Data::FormValidator->check($par,$profile));
return;
};
dance;
The output that I'm getting is showing that text[] is entirely invalid, which is understandable; what I'm trying to figure out is there any way to constrain the array as a whole and only remove the elements that don't match? I'm presuming that it might be doable using a filter, but I want to make sure I'm not just being silly. Any help would be appreciated.

Answer 1

Depending on how you're having your parameters parsed and presented to you, text[] could indeed be "entoirely invalid". I myself would not name a HTML form field 'text', just to avoid potential interactions with reserved words, and to alleviate confusion.
That being said, I would just call the field 'text' instead of 'text[]' and rely on your param parser to present $text or its equivalent as an array of values. Then iterate over them in your constraint method.
There will be a couple of gotchas, depending on the param parser that you use. For instance, CGI.pm will present multivariate fields in an array if there is more than one value submitted, but will present the same field as a scalar if only one value is submitted.