HTML::FormHandler::Manual::Catalyst - using HFH forms in Catalyst
version 0.40068
Manual Index
This part of the FormHandler Manual describes the use of the HTML::FormHandler
package in Catalyst controllers.
See the other FormHandler documentation at HTML::FormHandler::Manual, or the
base class at HTML::FormHandler.
Although HTML::FormHandler can be used in any Perl web application, module, or
script, one of its most common uses is in Catalyst applications.
Using a form takes only a few lines of code, so it's not necessary to have a
Catalyst base controller, although you could make a base controller for
FormHandler if you're doing more than the basics.
The following example uses chained dispatching. The 'form' method is called by
both the create and edit actions.
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')) );
}
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If you are 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.
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.
return unless $c->stash->{form}->process( item_id => $id );
You can also put your form in a Moose attribute in the controller.
package MyApp::Controller::Book;
use Moose;
BEGIN { extends 'Catalyst::Controller'; }
use MyApp::Form::Book;
has 'edit_form' => ( isa => 'MyApp::Form::Book', is => 'rw',
lazy => 1, default => sub { MyApp::Form::Book->new } );
Then you can process the form in your actions with
"$self->edit_form->process( params =>
$c->req->body_parameters );" or "my $result =
$self->edit_form->run( params => $c->req->body_parameters
);".
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';
....
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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.
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. 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' );
....
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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" );
}
}
FormHandler Contributors - see HTML::FormHandler
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.