3 Catalyst::Manual::Tutorial::AdvancedCRUD::FormFu - Catalyst Tutorial - Part 9: Advanced CRUD - FormFu
6 NOTE: This part of the tutorial is in progress and will be ready soon.
10 This is B<Part 9 of 10> for the Catalyst tutorial.
12 L<Tutorial Overview|Catalyst::Manual::Tutorial>
18 L<Introduction|Catalyst::Manual::Tutorial::Intro>
22 L<Catalyst Basics|Catalyst::Manual::Tutorial::CatalystBasics>
26 L<More Catalyst Basics|Catalyst::Manual::Tutorial::MoreCatalystBasics>
30 L<Basic CRUD|Catalyst::Manual::Tutorial::BasicCRUD>
34 L<Authentication|Catalyst::Manual::Tutorial::Authentication>
38 L<Authorization|Catalyst::Manual::Tutorial::Authorization>
42 L<Debugging|Catalyst::Manual::Tutorial::Debugging>
46 L<Testing|Catalyst::Manual::Tutorial::Testing>
54 L<Appendices|Catalyst::Manual::Tutorial::Appendices>
61 This portion of the tutorial explores L<HTML::FormFu|HTML::FormFu> and
62 how it can be used to manage forms, perform validation of form input,
63 as well as save and restore data to/from the database.
66 L<Catalyst::Manual::Tutorial::AdvancedCRUD|Catalyst::Manual::Tutorial::AdvancedCRUD>
67 for additional form management options other than
68 L<HTML::FormFu|HTML::FormFu>.
71 =head1 Install C<HTML::FormFu>
73 If you are following along in Ubuntu, it turns out that C<HTML::FormFu>
74 is not yet available as a package at the time this was written. To
75 install it with a combination of C<apt-get> packages and traditional
76 CPAN modules, first use C<apt-get> to install most of the modules
77 required by C<HTML::FormFu>:
79 sudo apt-get install libtest-nowarnings-perl libdatetime-format-builder-perl \
80 libdatetime-format-strptime-perl libdatetime-locale-perl \
81 libhtml-tokeparser-simple-perl liblist-moreutils-perl \
82 libregexp-copy-perl libregexp-common-perl libyaml-syck-perl libparams-util-perl
84 Then use the following command to install directly from CPAN the modules
85 that aren't available as Ubuntu/Debian packages via C<apt-get>:
87 sudo cpan File::ShareDir Task::Weaken Config::Any HTML::FormFu \
88 Catalyst::Controller::HTML::FormFu
91 =head1 C<HTML::FormFu> FORM CREATION
93 This section looks at how L<HTML::FormFu|HTML::FormFu> can be used to
94 add additional functionality to the manually created form from Part 4.
97 =head2 Inherit From C<Catalyst::Controller::HTML::FormFu>
99 First, change your C<lib/MyApp/Controller/Books.pm> to inherit from
100 L<Catalyst::Controller::HTML::FormFu|Catalyst::Controller::HTML::FormFu>
101 by changing the C<use base> line from the default of:
103 use base 'Catalyst::Controller';
105 to use the FormFu base controller class:
107 use base 'Catalyst::Controller::HTML::FormFu';
110 =head2 Add Action to Display and Save the Form
112 Open C<lib/MyApp/Controller/Books.pm> in your editor and add the
115 =head2 fu_form_create
117 Build an HTML::FormFu form for book creation and updates
121 sub fu_form_create :Local :FormConfig {
124 # Get the form that the :FormConfig attribute saved in the stash
125 my $form = $c->stash->{form};
127 # Check if the form as been submitted (vs. displaying the initial
128 # form) and if the data based validation. "submitted_and_valid"
129 # is shorthand for "$form->submitted && !$form->has_errors"
130 if ($form->submitted_and_valid) {
132 my $book = $c->model('DB::Books')->new_result({});
133 # Save the form data for the book
134 $form->save_to_model($book);
135 # Set a status message for the user
136 $c->flash->{status_msg} = 'Book created';
137 # Return to the books list
138 $c->response->redirect($c->uri_for('list'));
141 # Get the authors from the DB
142 my @authorObjs = $c->model("DB::Authors")->all();
143 # Create an array of arrayrefs where each arrayref is an author
145 foreach (sort {$a->last_name cmp $b->last_name} @authorObjs) {
146 push(@authors, [$_->id, $_->last_name]);
148 # Get the select added by the config file
149 my $select = $form->get_element({type => 'Select'});
150 # Add the authors to it
151 $select->options(\@authors);
155 $c->stash->{template} = 'books/fu_form_create.tt2';
159 =head2 Create a Form Config File
161 Although C<HTML::FormFu> supports any configuration file handled by
162 L<Config::Any|Config::Any>, most people tend to use YAML. First
163 create a directory to hold your form configuration files:
165 mkdir -p root/forms/books
167 Then create the file C<root/forms/books/fu_form_create.yml> and enter the
171 # indicator is the field that is used to test for form submission
173 # Start listing the form elements
175 # The first element will be a text field for the title
179 # This is an optional 'mouse over' title pop-up
181 title: Enter a book title here
186 title: Enter a rating between 1 and 5 here
193 =head2 Update the CSS
195 Edit C<root/src/ttsite.css> and add the following lines to the bottom of
205 color: [% site.col.error %];
208 These changes will display form elements vertically and also show error
209 messages in red. Note that we are pulling the color scheme settings
210 from the C<root/lib/config/col> file that was created by the TTSite
211 helper. This allows us to change the color used by various error styles
212 in the CSS from a single location.
215 =head2 Create a Template Page To Display The Form
217 Open C<root/src/books/fu_form_create.tt2> in your editor and enter the following:
219 [% META title = 'Create/Update Book' %]
221 [%# Render the HTML::FormFu Form %]
224 <p><a href="[% Catalyst.uri_for('list') %]">Return to book list</a></p>
227 =head2 Add Links for Create and Update via C<HTML::FormFu>
229 Open C<root/src/books/list.tt2> in your editor and add the following to
230 the bottom of the existing file:
234 <a href="[% Catalyst.uri_for('fu_form_create') %]">Create</a>
238 =head2 Test The <HTML::Widget> Create Form
240 Press C<Ctrl-C> to kill the previous server instance (if it's still
241 running) and restart it:
243 $ script/myapp_server.pl
245 Login as C<test01>. Once at the Book List page, click the HTML::FormFu
246 "Create" link to display for form produced by C<make_book_widget>. Fill
247 out the form with the following values: Title = "Internetworking with
248 TCP/IP Vol. II", Rating = "4", and Author = "Comer". Click Submit, and
249 you will be returned to the Book List page with a "Book created" status
252 Also note that this implementation allows you to can create books with
253 bogus information. Although we have constrained the authors with the
254 drop-down list, there are no restrictions on items such as the length of
255 the title (for example, you can create a one-letter title) and value for
256 the rating (you can use any number you want, and even non-numeric values
257 with SQLite). The next section will address this concern.
259 B<Note:> Depending on the database you are using and how you established
260 the columns in your tables, the database could obviously provide various
261 levels of "type enforcement" on your data. The key point being made in
262 the previous paragraph is that the I<web application> itself is not
263 performing any validation.
266 =head1 C<HTML::FormFu> VALIDATION AND FILTERING
268 Although the use of L<HTML::FormFu|HTML::FormFu> in the previous section
269 did provide an automated mechanism to build the form, the real power of
270 this module stems from functionality that can automatically validate and
271 filter the user input. Validation uses constraints to be sure that
272 users input appropriate data (for example, that the email field of a
273 form contains a valid email address). Filtering can be used to remove
274 extraneous whitespace from fields or to escape meta-characters in user
277 =head2 Add Constraints
280 Open C<root/forms/books/fu_form_create.yml> in your editor and update it
284 # indicator is the field that is used to test for form submission
286 # Start listing the form elements
288 # The first element will be a text field for the title
292 # This is an optional 'mouse over' title pop-up
294 title: Enter a book title here
295 # Add constraints for the field
297 # The user cannot leave this field blank
299 # Force the length to be between 2 and 30 chars
303 # Override the default of 'Invalid input'
304 message: Length must be between 2 and 30 characters
309 title: Enter a rating between 1 and 5 here
312 # Make sure it's a number
318 # Globally ensure that each field only specified one value
326 Kennedy Clark, C<hkclark@gmail.com>
328 Please report any errors, issues or suggestions to the author. The
329 most recent version of the Catalyst Tutorial can be found at
330 L<http://dev.catalyst.perl.org/repos/Catalyst/trunk/Catalyst-Manual/lib/Catalyst/Manual/Tutorial/>.
332 Copyright 2006, Kennedy Clark, under Creative Commons License
333 (L<http://creativecommons.org/licenses/by-nc-sa/2.5/>).