Catalyst::Manual::Tutorial::AdvancedCRUD - Catalyst Tutorial - Part 8: Advanced CRUD
-
-
=head1 OVERVIEW
This is B<Part 8 of 9> for the Catalyst tutorial.
=item 9
-L<Appendicies|Catalyst::Manual::Tutorial::Appendicies>
+L<Appendices|Catalyst::Manual::Tutorial::Appendices>
=back
-
-
=head1 DESCRIPTION
This part of the tutorial explores more advanced functionality for
In keeping with the Catalyst (and Perl) spirit of flexibility, there are
many different ways approach advanced CRUD operations in a Catalyst
environment. One alternative is to use
-L<Catalyst::Helper::Controller::Scaffold|Catalyst::Helper::Controller::Scaffold>
-to instantly construct a set of Controller methods and templates for
-basic CRUD operations. Although a popular subject in Quicktime movies
-that serve as promotional material for various frameworks, more
-real-world applications require more control. Other options include
-L<Data::FormValidator|Data::FormValidator> and
+L<Catalyst::Helper::Controller::Scaffold|Catalyst::Helper::Controller::Scaffold>
+to instantly construct a set of Controller methods and templates for
+basic CRUD operations. Although a popular subject in Quicktime
+movies that serve as promotional material for various frameworks,
+real-world applications generally require more control. Other
+options include L<Data::FormValidator|Data::FormValidator> and
L<HTML::FillInForm|HTML::FillInForm>.
-Here, we will make use of the L<HTML::Widget|HTML::Widget> to not only
-ease form creation, but to also provide validation of the submitted
-data. The approached used by the part of the tutorial is to slowly
-incorporate additional L<HTML::Widget|HTML::Widget> functionality in a
-step-wise fashion (we start with fairly simple form creation and then
-move on to more complex and "magical" features such as validation and
+Here, we will make use of the L<HTML::Widget|HTML::Widget> to not only
+ease form creation, but to also provide validation of the submitted
+data. The approached used by the part of the tutorial is to slowly
+incorporate additional L<HTML::Widget|HTML::Widget> functionality in a
+step-wise fashion (we start with fairly simple form creation and then
+move on to more complex and "magical" features such as validation and
auto-population/auto-saving).
-B<Note:> Part 8 of the tutorial is optional. Users who do not which to
-use L<HTML::Widget|HTML::Widget> may skip this section.
+B<Note:> Part 8 of the tutorial is optional. Users who do not wish to
+use L<HTML::Widget|HTML::Widget> may skip this part.
B<TIP>: Note that all of the code for this part of the tutorial can be
pulled from the Catalyst Subversion repository in one step with the
svn checkout http://dev.catalyst.perl.org/repos/Catalyst/trunk/examples/Tutorial@###
IMPORTANT: Does not work yet. Will be completed for final version.
-
-
=head1 C<HTML::WIDGET> FORM CREATION
This section looks at how L<HTML::Widget|HTML::Widget> can be used to
add additional functionality to the manually created form from Part 3.
-
=head2 Add the C<HTML::Widget> Plugin
Open C<lib/MyApp.pm> in your editor and add the following to the list of
-plugins (be sure to leave the existing plugins enabled:
+plugins (be sure to leave the existing plugins enabled):
HTML::Widget
-
=head2 Add a Form Creation Helper Method
Open C<lib/MyApp/Controller/Books.pm> in your editor and add the
sub make_book_widget {
my ($self, $c) = @_;
-
+
# Create an HTML::Widget to build the form
my $w = $c->widget('book_form')->method('post');
$w->element('Select', 'authors')->label('Authors')
->options(@authors);
$w->element('Submit', 'submit' )->value('submit');
-
+
# Return the widget
return $w;
}
This method provides a central location (so it can be called by multiple
-actions, such as create and edit) that builds an HTML::Wiget-based form
-with the appropriate fields. The "Get Authors" code uses DBIC to
-retrieve a list of model objects and then uses C<map> to quickly create
-a hash where the hash keys are the database primary keys from the
-authors table and the associated values are the last names of the
-authors.
-
+actions, such as C<create> and C<edit>) that builds an HTML::Widget-based
+form with the appropriate fields. The "Get Authors" code uses DBIC to
+retrieve a list of model objects and then uses C<map> to create a hash
+where the hash keys are the database primary keys from the authors table
+and the associated values are the last names of the authors.
=head2 Add Actions to Display and Save the Form
(e.g., C<hw_create_do> for a create operation but C<hw_update_do> to
update an existing book object).
-
=head2 Update the CSS
Edit C<root/src/ttsite.css> and add the following lines to the bottom of
messages in red. Note that we are pulling the color scheme settings
from the C<root/lib/config/col> file that was created by the TTSite
helper. This allows us to change the color used by various error styles
-in the CCS from a single location.
-
+in the CSS from a single location.
=head2 Create a Template Page To Display The Form
-C<root/src/books/hw_form.tt2>
+Open C<root/src/books/hw_form.tt2> in your editor and enter the following:
+
[% META title = 'Create/Update Book' %]
[% widget_result.as_xml %]
<p><a href="[% Catalyst.uri_for('list') %]">Return to book list</a></p>
-
=head2 Add Links for Create and Update via C<HTML::Widget>
Open C<root/src/books/list.tt2> in your editor and add the following to
<a href="[% Catalyst.uri_for('hw_update') %]">Update</a>
</p>
-
=head2 Test The <HTML::Widget> Create Form
Press C<Ctrl-C> to kill the previous server instance (if it's still
drop-down list, there are no restrictions on items such as the length of
the title (for example, you can create a one-letter title) and value for
the rating (you can use any number you want, and even non-numeric values
-with SQLite). The next section seeks to address this concern.
+with SQLite). The next section will address this concern.
B<Note:> Depending on the database you are using and how you established
the columns in your tables, the database could obviously provide various
the previous paragraph is that the I<web application> itself is not
performing any validation.
-
=head1 C<HTML::WIDGET> VALIDATION AND FILTERING
Although the use of L<HTML::Widget|HTML::Widget> in the previous section
extraneous whitespace from fields or to escape meta-characters in user
input.
-
=head2 Add Constraints and Filters to the Widget Creation Method
Open C<lib/MyApp/Controller/Books.pm> in your editor and update the
sub make_book_widget {
my ($self, $c) = @_;
-
+
# Create an HTML::Widget to build the form
my $w = $c->widget('book_form')->method('post');
my @authorObjs = $c->model("MyAppDB::Author")->all();
my @authors = map {$_->id => $_->last_name }
sort {$a->last_name cmp $b->last_name} @authorObjs;
-
+
# Create the form feilds
$w->element('Textfield', 'title' )->label('Title')->size(60);
$w->element('Textfield', 'rating' )->label('Rating')->size(1);
=back
-
=head2 Rebuild the Form Submission Method to Include Validation
Edit C<lib/MyApp/Controller/Books.pm> and change C<hw_create_do> to
=back
-
=head2 Try Out the Form
Press C<Ctrl-C> to kill the previous server instance (if it's still running) and restart it:
C<constraint> items will validate the logic and insert feedback as
appropriate.
-
=head1 Enable C<DBIx::Class::HTMLWidget> Support
In this section we will take advantage of some of the "auto-population"
=item *
-fill_wiget()
+fill_widget()
Takes data from the database and transfers it to your form widget.
In other words, the two methods are a mirror image of each other: one
reads from the database while the other writes to the database.
-
=head2 Add C<DBIx::Class::HTMLWidget> to DBIC Model
In order to use L<DBIx::Class::HTMLWidget|DBIx::Class::HTMLWidget>, we
__PACKAGE__->load_components(qw/PK::Auto Core HTMLWidget/);
-
=head2 Use C<populate_from_widget> in C<hw_create_do>
Edit C<lib/MyApp/Controller/Books.pm> and update C<hw_create_do> to
between tables.
-
=head1 AUTHOR
Kennedy Clark, C<hkclark@gmail.com>
-Please report any errors, issues or suggestions to the author.
-
-Copyright 2006, Kennedy Clark. All rights reserved.
-
-This library is free software; you can redistribute it and/or modify it under the same terms as Perl itself.
-
-Version: .94
+Please report any errors, issues or suggestions to the author. The
+most recent version of the Catlayst Tutorial can be found at
+L<http://dev.catalyst.perl.org/repos/Catalyst/trunk/Catalyst-Runtime/lib/Catalyst/Manual/Tutorial/>.
+Copyright 2006, Kennedy Clark, under Creative Commons License
+(L<http://creativecommons.org/licenses/by-nc-sa/2.5/>).
projects / catagits/Catalyst-Runtime.git / blobdiff