NAME
    FormValidator::Lite - lightweight form validation library

SYNOPSIS
        use FormValidator::Lite;

        FormValidator::Lite->load_constraints(qw/Japanese/);

        my $q = CGI->new();
        my $validator = FormValidator::Lite->new($q);
        my $res = $validator->check(
            name => [qw/NOT_NULL/],
            name_kana => [qw/NOT_NULL KATAKANA/],
            {mails => [qw/mail1 mail2/]} => ['DUPLICATION'],
        );
        if ( ..... return_true_when_if_error() ..... ) {
            $validator->set_error('login_id' => 'DUPLICATION');
        }
        if ($validator->has_error) {
            ...
        }

        # in your tmpl
        <ul>
        ? for my $msg ($validator->get_error_messages) {
            <li><?= $msg ?></li>
        ? }
        </ul>

DESCRIPTION
    FormValidator::Lite is simple, fast implementation for form validation.

    IT'S IN BETA QUALITY. API MAY CHANGE IN FUTURE.

HOW TO WRITE YOUR OWN CONSTRAINTS
        http parameter comes from $_
        validator args comes from @_

METHODS
    my $validator = FormValidator::Lite->new($q);
        Create a new instance.

        $q is query like object, such as Apache::Request, CGI.pm,
        Plack::Request. The object MUST have a "$q->param" method.

    $validator->query()
    $validator->query($query)
        Getter/Setter for query like object.

    $validator->check(@rule_ary)
            my $res = $validator->check(
                name      => [qw/NOT_NULL/],
                name_kana => [qw/NOT_NULL KATAKANA/],
                {mails => [qw/mail1 mail2/]} => ['DUPLICATION'],
            );

        This method do validation. You can write a rule in @rule_ary. In
        above example code, *name* is a parameter name, *NOT_NULL*,
        *KATAKANA* and *DUPLICATION* are name of constraints.

    $validator->is_error($key)
        Return true value if parameter named $key got error.

    $validator->is_valid()
        Return true value if $validator don't detects error.

        This is same as "!$validator->has_error()".

    $validator->has_error()
        Return true value if $validator detects error.

        This is same as "!$validator->is_valid()".

    $validator->set_error($param, $rule_name)
        Set new error to parameter named "<$param">. The rule name is
        "<$rule_name">.

    $validator->errors()
        Return whole errors as HashRef.

            {
                'foo' => { 'NOT_NULL' => 1, 'INT' => 1 },
                'bar' => { 'EMAIL' => 1, },
            }

    $validator->load_constraints($name)
            $validator->load_constraints("DATE", "Email");

            # or load your own constraints
            $validator->load_constraints("+MyApp::FormValidator::Lite::Constraint");

        There is a import style.

            use FormValidator::Lite qw/Date Email/;

        load constraint components named
        "FormValidator::Lite::Constraint::${name}".

    $validator->load_function_message($lang)
            $validator->load_function_message('ja');

        Load function message file.

        Currently, FormValidator::Lite::Messages::ja and
        FormValidator::Lite::Messages::en are available.

    $validator->set_param_message($param => $message, ...)
            $validator->set_param_message(
                name => 'Your Name',
            );

        Make relational map for the parameter name to human readable name.

    $validator->set_message_data({ message => $msg, param => $param,
    function => $function })
            $v->set_message_data(YAML::Load(<<'...'));
            ---
            message:
              zip.jzip: Please input correct zip number.
            param:
              name: Your Name
            function:
              not_null: "[_1] is empty"
              hiragana: "[_1] is not Hiragana"
            ...

        Setup error message map.

    $validator->set_message("$param.$func" => $message)
            $v->set_message('zip.jzip' => 'Please input correct zip number.');

        Set error message for the $param and $func.

    my @errors = $validator->get_error_messages()
    my $errors = $validator->get_error_messages()
        Get whole error messages for "<$q"> in array/arrayref. This method
        returns array in list context, otherwise HashRef.

    my $msg = $validator->get_error_message($param => $func)
        Generate error message for parameter $param and function named
        $func.

    my @msgs = $validator->get_error_messages_from_param($param)
        Get error messages by $q for parameter $param.

WHY NOT FormValidator::Simple?
    Yes, I know. This module is very similar with FV::S.

    But, FormValidator::Simple is too heavy for me. FormValidator::Lite is
    fast!

       Perl: 5.010000
       FVS: 0.23
       FVL: 0.02
                               Rate FormValidator::Simple   FormValidator::Lite
       FormValidator::Simple  353/s                    --                  -75%
       FormValidator::Lite   1429/s                  304%                    --

AUTHOR
    Tokuhiro Matsuno <tokuhirom AAJKLFJEF@ gmail.com>

THANKS TO
    craftworks

    nekokak

    tomi-ru

SEE ALSO
    FormValidator::Simple, Data::FormValidator, HTML::FormFu

LICENSE
    This library is free software; you can redistribute it and/or modify it
    under the same terms as Perl itself.