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Catalyst::Manual::Tutorial::09_AdvancedCRUD::09_FormHandUser3Contributed Perl DocuCatalyst::Manual::Tutorial::09_AdvancedCRUD::09_FormHandler(3pm) NAME
Catalyst::Manual::Tutorial::09_AdvancedCRUD::09_FormHandler - Catalyst Tutorial - Chapter 9: Advanced CRUD - FormHandler OVERVIEW
This is Chapter 9 of 10 for the Catalyst tutorial. Tutorial Overview 1. Introduction 2. Catalyst Basics 3. More Catalyst Basics 4. Basic CRUD 5. Authentication 6. Authorization 7. Debugging 8. Testing 9. 09_Advanced CRUD::09_FormHandler 10. Appendices DESCRIPTION
This portion of the tutorial explores HTML::FormHandler and how it can be used to manage forms, perform validation of form input, and save and restore data to or from the database. This was written using HTML::FormHandler version 0.28001. See Catalyst::Manual::Tutorial::09_AdvancedCRUD for additional form management options other than HTML::FormHandler. Install HTML::FormHandler Use the following command to install HTML::FormHandler::Model::DBIC directly from CPAN: sudo cpan HTML::FormHandler::Model::DBIC It will install HTML::FormHandler as a prerequisite. Also, add: requires 'HTML::FormHandler::Model::DBIC'; to your "Makefile.PL". HTML
::FormHandler FORM CREATION This section looks at how HTML::FormHandler can be used to add additional functionality to the manually created form from Chapter 4. Using FormHandler in your controllers FormHandler doesn't have a Catalyst base controller, because interfacing to a form is only a couple of lines of code. Create a Book Form Create the directory "lib/MyApp/Form". Create "lib/MyApp/Form/Book.pm": package MyApp::Form::Book; use HTML::FormHandler::Moose; extends 'HTML::FormHandler::Model::DBIC'; use namespace::autoclean; has '+item_class' => ( default =>'Books' ); has_field 'title'; has_field 'rating' => ( type => 'Integer' ); has_field 'authors' => ( type => 'Multiple', label_column => 'last_name' ); has_field 'submit' => ( type => 'Submit', value => 'Submit' ); __PACKAGE__->meta->make_immutable; 1; Add Action to Display and Save the Form At the top of the "lib/MyApp/Controller/Books.pm" add: use MyApp::Form::Book; Add the following methods: =head2 create Use HTML::FormHandler to create a new book =cut sub create : Chained('base') PathPart('create') Args(0) { my ($self, $c ) = @_; my $book = $c->model('DB::Book')->new_result({}); return $self->form($c, $book); } =head2 form Process the FormHandler book form =cut sub form { my ( $self, $c, $book ) = @_; my $form = MyApp::Form::Book->new; # Set the template $c->stash( template => 'books/form.tt2', form => $form ); $form->process( item => $book, params => $c->req->params ); return unless $form->validated; # Set a status message for the user & return to books list $c->response->redirect($c->uri_for($self->action_for('list'), {mid => $c->set_status_msg("Book created")})); } These two methods could be combined at this point, but we'll use the 'form' method later when we implement 'edit'. Create a Template Page To Display The Form Open "root/src/books/form.tt2" in your editor and enter the following: [% META title = 'Create/Update Book' %] [%# Render the HTML::FormHandler Form %] [% form.render %] <p><a href="[% c.uri_for(c.controller.action_for('list')) %]">Return to book list</a></p> Add Link for Create Open "root/src/books/list.tt2" in your editor and add the following to the bottom of the existing file: ... <p> HTML::FormHandler: <a href="[% c.uri_for(c.controller.action_for('create')) %]">Create</a> </p> This adds a new link to the bottom of the book list page that we can use to easily launch our HTML::FormHandler-based form. Test The HTML::FormHandler Create Form Press "Ctrl-C" to kill the previous server instance (if it's still running) and restart it: $ script/myapp_server.pl Login as "test01" (password: mypass). Once at the Book List page, click the new HTML::Formhandler "Create" link at the bottom to display the form. Fill in the following values: Title = "Internetworking with TCP/IP Vol. II" Rating = "4" Author = "Comer" Click the Submit button, and you will be returned to the Book List page with a "Book created" status message displayed. Note that because the 'Author' column is a Select list, only the authors in the database can be entered. The 'ratings' field will only accept integers. Add Constraints Open "lib/MyApp/Form/Book.pm" in your editor. Restrict the title size and make it required: has_field 'title' => ( minlength => 5, maxlength => 40, required => 1 ); Add range constraints to the 'rating' field: has_field 'rating' => ( type => 'Integer', range_start => 1, range_end => 5 ); The 'authors' relationship is a 'many-to-many' pseudo-relation, so this field can be set to Multiple to allow the selection of multiple authors; also, make it required: has_field 'authors' => ( type => 'Multiple', label_column => 'last_name', required => 1 ); Note: FormHandler automatically strips whitespace at the beginning and end of fields. If you want some other kind of stripping (or none) you can specify it explicitly; see HTML::FormHandler::Manual. Try Out the Updated Form Press "Ctrl-C" to kill the previous server instance (if it's still running) and restart it: $ script/myapp_server.pl Make sure you are still logged in as "test01" and try adding a book with various errors: title less than 5 characters, non-numeric rating, a rating of 0 or 6, etc. Also try selecting one, two, and zero authors. Create the 'edit' method Edit "lib/MyApp/Controller/Books.pm" and add the following method: =head2 edit Edit an existing book with FormHandler =cut sub edit : Chained('object') PathPart('edit') Args(0) { my ( $self, $c ) = @_; return $self->form($c, $c->stash->{object}); } Update the "root/src/books/list.tt2", adding an 'edit' link below the "Delete" link to use the FormHandler edit method: <td> [% # Add a link to delete a book %] <a href="[% c.uri_for(c.controller.action_for('delete'), [book.id]) %]">Delete</a> [% # Add a link to edit a book %] <a href="[% c.uri_for(c.controller.action_for('edit'), [book.id]) %]">Edit</a> </td> Try Out the Edit/Update Feature Press "Ctrl-C" to kill the previous server instance (if it's still running) and restart it: $ script/myapp_server.pl Make sure you are still logged in as "test01" and go to the <http://localhost:3000/books/list> URL in your browser. Click the "Edit" link next to "Internetworking with TCP/IP Vol. II", change the rating to a 3, the "II" at end of the title to the number "2", add Stevens as a co-author (control-click), and click Submit. You will then be returned to the book list with a "Book edited" message at the top in green. Experiment with other edits to various books. See additional documentation on FormHandler HTML::FormHandler::Manual HTML::FormHandler #formhandler on irc.perl.org mailing list: http://groups.google.com/group/formhandler code: http://github.com/gshank/html-formhandler/tree/master AUTHOR
Gerda Shank, "gshank@cpan.org" Copyright 2009, Gerda Shank, Perl Artistic License perl v5.14.2 2012-01-20 Catalyst::Manual::Tutorial::09_AdvancedCRUD::09_FormHandler(3pm)
