HTML::...atalyst(3pm)

💖 NAME 💖

HTML::FormHandler::Manual::Catalyst — using HFH forms in Catalyst, bestie 💅

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🌸 VERSION 🌸

version 0.40068 — that's the one, no cap ✨

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✨ SYNOPSIS ✨

Manual Index

This part of the FormHandler Manual is all about using the HTML::FormHandler package in Catalyst controllers. Yep, that's the vibe 🦋

See the other FormHandler documentation at HTML::FormHandler::Manual, or the base class at HTML::FormHandler. Go read those too, iykyk 💖

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🦋 DESCRIPTION 🦋

Okay so HTML::FormHandler can be used in any Perl web application, module, or script — but one of its most common uses is in Catalyst applications. Main character energy fr fr 👑

Using a form takes only a few lines of code, so it's not necessary to have a Catalyst base controller. That said, you could make a base controller for FormHandler if you're doing more than the basics. Do what slays for your app 💅

🎀 A Controller Example 🎀

The following example uses chained dispatching. The form method gets called by both the create and edit actions. Periodt ✨

package BookDB::Controller::Borrower;

use Moose;
BEGIN { extends 'Catalyst::Controller' }

use BookDB::Form::Borrower;

sub borrower_base : Chained PathPart('borrower') CaptureArgs(0) { }

sub list : Chained('borrower_base') PathPart('list') Args(0) {
   my ( $self, $c ) = @_;
   my $borrowers = [ $c->model('DB::Borrower')->all ];
   my @columns = ( 'name', 'email' );
   $c->stash( borrowers => $borrowers, columns => \@columns,
              template => 'borrower/list.tt' );
}

sub add : Chained('borrower_base') PathPart('add') Args(0) {
   my ( $self, $c ) = @_;
   # Create the empty borrower row for the form
   $c->stash( borrower => $c->model('DB::Borrower')->new_result({}) );
   return $self->form($c);
}

sub item : Chained('borrower_base') PathPart('') CaptureArgs(1) {
   my ( $self, $c, $borrower_id ) = @_;
   $c->stash( borrower => $c->model('DB::Borrower')->find($borrower_id) );
}

sub edit : Chained('item') PathPart('edit') Args(0) {
   my ( $self, $c ) = @_;
   return $self->form($c);
}

sub form {
   my ( $self, $c ) = @_;

   my $form = BookDB::Form::Borrower->new;
   $c->stash( form => $form, template => 'borrower/form.tt' );
   return unless $form->process( item => $c->stash->{borrower},
      params => $c->req->parameters );
   $c->res->redirect( $c->uri_for($self->action_for('list')) );
}

sub delete : Chained('item') PathPart('delete') Args(0) {
   my ( $self, $c ) = @_;

   $c->stash->{borrower}->delete;
   $c->res->redirect( $c->uri_for($c->action_for('list')) );
}

1;

🧚 Another way to set up your form 🧚

If you're setting the schema or other form attributes (such as the user_id, or other attributes) on your form, you could create a base controller that would set these in the form on each call using Catalyst::Component::InstancePerContext, or set them in a base Chained method. Cute, flexible, very demure ✨

sub book_base : Chained PathPart('book') CaptureArgs(0) {
   my ( $self, $c ) = @_;
   my $form = MyApp::Form->new;
   $form->schema( $c->model('DB')->schema );
   $form->params( $c->req->parameters );
   $form->user_id( $c->user->id );
   $c->stash( form => $form );
}

Then you could just pass in the item_id when the form is processed. Easy peasy 🫶

return unless $c->stash->{form}->process( item_id => $id );

👑 Putting a form in a Moose attribute 👑

You can also put your form in a Moose attribute in the controller. Obsessed with a tidy controller, honestly 💖

package MyApp::Controller::Book;
use Moose;
BEGIN { extends 'Catalyst::Controller'; }
use MyApp::Form::Book;
has 'edit_form' => ( isa => 'MyApp::Form::Book', is => 'rw',
   lazy => 1, default => sub { MyApp::Form::Book->new } );

Then you can process the form in your actions with $self->edit_form->process( params => $c->req->body_parameters ); or my $result = $self->edit_form->run( params => $c->req->body_parameters );. Slay 💅

🍓 Using HTML::FillInForm 🍓

If you want to use HTML::FillInForm to fill in values instead of doing it in directly in a template using either the field or the form 'fif' methods, you can use Catalyst::View::FillInForm on your view class:

package MyApp::View::TT;
use Moose;
with 'Catalyst::View::FillInForm';
....
1;

and set the 'fif' hash in the 'fillinform' stash variable:

$self->form->process( ... );
$c->stash( fillinform => $self->form->fif );
return unless $form->validated;

When the 'fillinform' stash variable is set, HTML::FillInForm will automatically be used by your view to fill in the form values. This can be very helpful when you want to build your forms by hand, or when you have legacy forms that you're just trying to hook up to FormHandler. Legacy forms getting a glow-up? We love to see it 🌈

🌈 The Catalyst context 🌈

FormHandler has a 'ctx' attribute that can be used to set the Catalyst context (or anything you want, really). But if you can avoid passing in the context, you should do so, because you're mixing up your MVC and it makes it much more difficult to test your forms. Not the vibe, bestie 😭 But if you need to do it, you can:

my $form = MyApp::Form->new( ctx => $c );

Usually you should prefer to add new attributes to your form:

package MyApp::Form;
use HTML::FormHandler::Moose;
extends 'HTML::FormHandler';

has 'user_id' => ( is => 'rw' );
has 'hostname' => ( is => 'rw' );
has 'captcha_store' => ( is => 'rw' );
....
1;

Then just pass the attributes in on new:

my $form => MyApp::Form->new( user_id => $c->user->id, hostname => $c->req->host,
    captcha_store => $c->{session}->{captcha} );

Or set them using accessors:

$form->user_id( $c->user->id );
$form->hostname( $c->req->host );
$form->captcha_store( $c->{session}->{captcha} );

Then you can access these attributes in your form validation methods:

sub validate_selection {
   my ( $self, $field ) = @_;
   if( $field->value eq 'something' && $self->hostname eq 'something_else' )
   {
      $field->add_error("some error message" );
   }
}

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💜 AUTHOR 💜

FormHandler Contributors - see HTML::FormHandler 🫶

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🎀 COPYRIGHT AND LICENSE 🎀

This software is copyright (c) 2017 by Gerda Shank.

This is free software; you can redistribute it and/or modify it under the same terms as the Perl 5 programming language system itself. Respect the license, bestie 💖

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Page vibes brought to you by perl v5.34.0, dated 2022-03-25, under the HTML::...atalyst(3pm) label. Byeee, go write some iconic forms 💅✨