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CGI::FormBuilder::Config::Simple - deploy web forms w/ .ini file


Version 0.12


This module exists to synthesize the abstractions of CGI::FormBuilder with those of Config::Simple to make it nearly possible to deploy a working form and database application by simply configuring an ini file. Add to that config file your data processing routines, perhaps a template from the design team and you are done. This module handles converting a config file into a form, validating user input and all that.

A developer would still be required to write methods to process their data, but much of the rest of the work will be covered by this modules' methods, and those of the ones just cited from which it inherits its methods.

For some sample code, please see: t/My/Module/ which provides scaffolding for the test suite.

    -- signup.cgi --

    use lib qw(lib);
    use MyModule::Signup;
        # see below for details . . . 

    my $debug_level = 0; # raise to 3 for noisy logs 
    my $signup = MyModule::Signup->new({ config_file => '/path/to/config/file.ini' });
        # should create a config object respecting ->param() method 
        # and embed that object at $self->{'cfg'}
    my $signup_form_html = $signup->render_web_form('sign_up',$debug_level) or
        carp("$0 died rendering a signup form. $signup->errstr. $!");

    print <<"END_OF_HTML";
    Content-Type: text/html; charset=utf-8 \n\n


    -- /lib/MyModule/ -- 

    package MyModule::Signup;

    use base 'CGI::FormBuilder::Config::Simple';

    sub new {
      my $class = shift;
      my $defaults = shift;
      my $self = {};

      $self->{'cfg'} = Config::Simple::Extended->new(
            { filename => $defaults->{'config_file'} } );
            # or use its ->inherit() method to overload configurations 

      my $db = $self->{'cfg'}->get_block('db');
      $self->{'dbh'} = MyModule::DB->connect($db);
            # a DBI->connect() object

      # whatever else you need in your constructor

      bless $self, $class;
      return $self;

    sub sample_data_processing_method {
      my $self = shift;

        .  .  .  


    sub get_that_field_options {
      my $self = shift;
      my @options = ('an_option','another_option');
      return \@options;

    # the code above should render, validate and process your data 
    # Now write a config file looking like this, and your are done

    -- conf.d/ --

       . . . 

    title='Signup Form'
    submit='Lets Get Started'
    # debug = 0 | 1 | 2 | 3

    ;values=\%hash | \@array

    label='This field'
    validation_error='this_field should be made up of words'
    label='That field'
    validation_error='that_field should include only legal options'
       . . . 



Given an object, with a configuration object accessible at $self->{'cfg'}, honoring the ->param() method provided by Config::Simple and Config::Simple::Extended (but possibly others), render the html for a web form for service.

This method takes an optional second argument, used to set the debug level. Use 0 or undefined for quiet operation.

Use 1 or greater to see information about the form being validated, 2 or greater to watch the fieldsets being validated, 3 or greater to watch the fields being validated and 4 or greater to dump the contents of pre-defined field options during field validation.

Use a 5 or greater to see information about the form being built, 6 or greater to watch the fieldsets being built, 7 or greater to watch the fields being built and 8 or greater to dump the contents of pre-defined field options.


In your My::Module which inherits from this one, you need to write a method for every fieldset.process_protocol in the configuration file.

This method will be called by the ->render_web_form() method and cycle through each fieldset and execute your application specific database interactions and other required data processing.


This method validates each fieldset defined in the configuration file for a form, returning 0 if all fields validate, and otherwise a positive integer representing a count of fields which failed the validation test.

This method will also process each method listed in the custom_validation_methods attribute of the stanza named for the form. Each of these methods, which must be written by the user writing the module which inherits from this one, should return a positive integer for invalid data or a zero (0) if the data that method checks is valid.


This method validates each field defined in the configuration file for a fieldset, returning 0 if all fields validate, and otherwise a positive integer representing a count of fields which failed the validation test.


This method validates a field, returning 0 if the field validates, and otherwise 1. It uses the validate attribute from the configuration file to make a regex comparison. If that validate has a value beginning with an ampersand '&', the code reference is interpretted as an object method.

This method must either return an array of array_references of key->value pairs representing valid options (for a selector), or otherwise an integer reflecting whether the field is invalid, again 0 for valid or 1 for invalid.

The user must write the code reference in the module which inherits from this one.

Presently having that coderef return the array of array_refs has been tested, but the case where it returns 0 or 1, has not yet been exercised in testing. Buyer Beware and please share your experience, bug reports, new test cases and patches.


Parses the configuration object for the fields required to build a form's fieldset and calls ->build_field() for each field listed in the fields attribute of the fieldset stanza in that configuration file, to compile the pieces necessary to configure the CGI::FormBuilder $form object.


Parses the configuration object for the attributes used to configure a CGI::FormBuilder->field() object. In reading the field attributes from the configuration file, it ignores 'validation_error', 'enabled' and the now deprecated 'disabled'.

errstr('Error description')

Append its argument, if any, to the error string, and return the result, returning undef if no error message has been set. Each error is prepended with a <li> list item tag, and the results are imagined to be rendered in html between <ul> unordered list tags.


Hugh Esco, <hesco at>


Please report any bugs or feature requests to bug-cgi-formbuilder-config-simple at, or through the web interface at I will be notified, and then you'll automatically be notified of progress on your bug as I make changes.


You can find documentation for this module with the perldoc command.

    perldoc CGI::FormBuilder::Config::Simple

You can also look for information at:


My appreciation to our team at YMD Partners, LLC, Bruce Dixon and Ida Hakim. Thank you for being a part of this business and for the contributions you make to serving our clients.

I want to acknowledge the support of the Green Party of Texas for making possible development of this module. An exciting if simple project of theirs serves as the first real world test of this idea which had been kicking about my head for a while.

And of course this work would not have been possible without the prior contributions to the CPAN repository made by Sherzod Ruzmetov, author of Config::Simple and Nate Wiger, author of CGI::FormBuilder, nor of course all the brilliant folks who developed Perl.


Copyright 2010 Hugh Esco.

This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; version 2 dated June, 1991 or at your option any later version.

This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.

A copy of the GNU General Public License is available in the source tree; if not, write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.