# Load plugins
use Catalyst qw/-Debug
- ConfigLoader
- Static::Simple
+ ConfigLoader
+ Static::Simple
- StackTrace
- /;
+ StackTrace
+ /;
B<Note:> Recent versions of C<Catalyst::Devel> have used a variety of
techniques to load these plugins/flags. For example, you might see
browser, not in the console window from which you're running your
application, which is where logging output usually goes.
+Make sure that when adding new plugins that you include them as a new
+dependancies within the Makefile.PL file. For example, after adding
+the StackTrace plugin the Makefile.PL should include the following
+line:
+
+ requires 'Catalyst::Plugin::StackTrace';
+
+
B<Notes:>
=over 4
# Retrieve all of the book records as book model objects and store in the
# stash where they can be accessed by the TT template
- # $c->stash->{books} = [$c->model('DB::Books')->all];
+ # $c->stash->{books} = [$c->model('DB::Book')->all];
# But, for now, use this code until we create the model later
$c->stash->{books} = '';
--
-- Create a very simple database to hold book and author information
--
- CREATE TABLE books (
+ CREATE TABLE book (
id INTEGER PRIMARY KEY,
title TEXT ,
rating INTEGER
);
- -- 'book_authors' is a many-to-many join table between books & authors
- CREATE TABLE book_authors (
+ -- 'book_author' is a many-to-many join table between books & authors
+ CREATE TABLE book_author (
book_id INTEGER,
author_id INTEGER,
PRIMARY KEY (book_id, author_id)
);
- CREATE TABLE authors (
+ CREATE TABLE author (
id INTEGER PRIMARY KEY,
first_name TEXT,
last_name TEXT
---
--- Load some sample data
---
- INSERT INTO books VALUES (1, 'CCSP SNRS Exam Certification Guide', 5);
- INSERT INTO books VALUES (2, 'TCP/IP Illustrated, Volume 1', 5);
- INSERT INTO books VALUES (3, 'Internetworking with TCP/IP Vol.1', 4);
- INSERT INTO books VALUES (4, 'Perl Cookbook', 5);
- INSERT INTO books VALUES (5, 'Designing with Web Standards', 5);
- INSERT INTO authors VALUES (1, 'Greg', 'Bastien');
- INSERT INTO authors VALUES (2, 'Sara', 'Nasseh');
- INSERT INTO authors VALUES (3, 'Christian', 'Degu');
- INSERT INTO authors VALUES (4, 'Richard', 'Stevens');
- INSERT INTO authors VALUES (5, 'Douglas', 'Comer');
- INSERT INTO authors VALUES (6, 'Tom', 'Christiansen');
- INSERT INTO authors VALUES (7, 'Nathan', 'Torkington');
- INSERT INTO authors VALUES (8, 'Jeffrey', 'Zeldman');
- INSERT INTO book_authors VALUES (1, 1);
- INSERT INTO book_authors VALUES (1, 2);
- INSERT INTO book_authors VALUES (1, 3);
- INSERT INTO book_authors VALUES (2, 4);
- INSERT INTO book_authors VALUES (3, 5);
- INSERT INTO book_authors VALUES (4, 6);
- INSERT INTO book_authors VALUES (4, 7);
- INSERT INTO book_authors VALUES (5, 8);
+ INSERT INTO book VALUES (1, 'CCSP SNRS Exam Certification Guide', 5);
+ INSERT INTO book VALUES (2, 'TCP/IP Illustrated, Volume 1', 5);
+ INSERT INTO book VALUES (3, 'Internetworking with TCP/IP Vol.1', 4);
+ INSERT INTO book VALUES (4, 'Perl Cookbook', 5);
+ INSERT INTO book VALUES (5, 'Designing with Web Standards', 5);
+ INSERT INTO author VALUES (1, 'Greg', 'Bastien');
+ INSERT INTO author VALUES (2, 'Sara', 'Nasseh');
+ INSERT INTO author VALUES (3, 'Christian', 'Degu');
+ INSERT INTO author VALUES (4, 'Richard', 'Stevens');
+ INSERT INTO author VALUES (5, 'Douglas', 'Comer');
+ INSERT INTO author VALUES (6, 'Tom', 'Christiansen');
+ INSERT INTO author VALUES (7, 'Nathan', 'Torkington');
+ INSERT INTO author VALUES (8, 'Jeffrey', 'Zeldman');
+ INSERT INTO book_author VALUES (1, 1);
+ INSERT INTO book_author VALUES (1, 2);
+ INSERT INTO book_author VALUES (1, 3);
+ INSERT INTO book_author VALUES (2, 4);
+ INSERT INTO book_author VALUES (3, 5);
+ INSERT INTO book_author VALUES (4, 6);
+ INSERT INTO book_author VALUES (4, 7);
+ INSERT INTO book_author VALUES (5, 8);
Then use the following command to build a C<myapp.db> SQLite database:
$ sqlite3 myapp.db
SQLite version 3.5.9
Enter ".help" for instructions
- sqlite> select * from books;
+ sqlite> select * from book;
1|CCSP SNRS Exam Certification Guide|5
2|TCP/IP Illustrated, Volume 1|5
3|Internetworking with TCP/IP Vol.1|4
Or:
- $ sqlite3 myapp.db "select * from books"
+ $ sqlite3 myapp.db "select * from book"
1|CCSP SNRS Exam Certification Guide|5
2|TCP/IP Illustrated, Volume 1|5
3|Internetworking with TCP/IP Vol.1|4
".q" to exit from SQLite from the SQLite interactive mode and return to
your OS command prompt.
+Please note that here we have chosen to use 'singular' table names. This
+is because the default inflection code for L<DBIx::Class:Schema::Loader>
+does NOT handle plurals. There has been much philosophical discussion
+on whether table names should be plural or singular. There is no one
+correct answer, as long as one makes a choice and remains consistent
+with it. If you prefer plural table names (e.g. they are easier and
+more natural to read) then you will need to pass it an inflect_map
+option. See L<DBIx::Class:Schema::Loader> for more information.
+
For using other databases, such as PostgreSQL or MySQL, see
L<Appendix 2|Catalyst::Manual::Tutorial::Appendices>.
'print "$Catalyst::Model::DBIC::Schema::VERSION\n"'
0.23
+(please note that the '\' above is a line continuation marker and
+should NOT be included as part of the command)
+
If you don't have version 0.23 or higher, please run this command
to install it directly from CPAN:
created "/home/me/MyApp/script/../lib/MyApp/Model/DB.pm"
created "/home/me/MyApp/script/../t/model_DB.t"
+(please note that the '\' above is a line continuation marker and
+should NOT be included as part of the command)
+
The C<script/myapp_create.pl> command breaks down like this:
=over 4
find that C<lib/MyApp> contains a C<Schema> subdirectory, which then
has a subdirectory called "Result". This "Result" subdirectory then
has files named according to each of the tables in our simple database
-(C<Authors.pm>, C<BookAuthors.pm>, and C<Books.pm>). These three
+(C<Author.pm>, C<BookAuthor.pm>, and C<Book.pm>). These three
files are called "Result Classes" in DBIx::Class nomenclature. Although the
Result Class files are named after tables in our database, the classes
correspond to the I<row-level data> that is returned by DBIC (more on
$ script/myapp_create.pl model DB DBIC::Schema MyApp::Schema \
create=static components=TimeStamp dbi:SQLite:myapp.db
$
+ $ # Note that the '\' above is a line continuation marker and
+ $ # should NOT be included as part of the command
+
+ $
$ # Now convert the existing files over
$ cd lib/MyApp/Schema
$ perl -MIO::All -e 'for (@ARGV) { my $s < io($_); $s =~ s/.*\n\# You can replace.*?\n//s;
C<lib/MyApp/Schema/Result> (we will be starting to add some
"customized relationship information in the section below).
-The C<script/myapp_create.pl> command breaks down like this:
-
-=over 4
-
-=item *
-
-C<DB> is the name of the model class to be created by the helper in
-C<lib/MyApp/Model>.
-
-=item *
-
-C<DBIC::Schema> is the type of the model to create.
-
-=item *
-
-C<MyApp::Schema> is the name of the DBIC schema file written to
-C<lib/MyApp/Schema.pm>.
-
-=item *
-
-Because we specified C<create=dynamic> to the helper, it use
-L<DBIx::Class::Schema::Loader|DBIx::Class::Schema::Loader> to
-dynamically load the schema information from the database every time
-the application starts.
-
-=item *
-
-And finally, C<dbi:SQLite:myapp.db> is the standard DBI connect string
-for use with SQLite.
-
-=back
-
=head1 ENABLE THE MODEL IN THE CONTROLLER
Open C<lib/MyApp/Controller/Books.pm> and un-comment the model code we
left disabled earlier so that your version matches the following (un-
-comment the line containing C<[$c-E<gt>model('DB::Books')-E<gt>all]>
+comment the line containing C<[$c-E<gt>model('DB::Book')-E<gt>all]>
and delete the next 2 lines):
=head2 list
# Retrieve all of the book records as book model objects and store in the
# stash where they can be accessed by the TT template
- $c->stash->{books} = [$c->model('DB::Books')->all];
+ $c->stash->{books} = [$c->model('DB::Book')->all];
# Set the TT template to use. You will almost always want to do this
# in your action methods (action methods respond to user input in
$c->stash->{template} = 'books/list.tt2';
}
-B<TIP>: You may see the C<$c-E<gt>model('DB::Books')> un-commented
-above written as C<$c-E<gt>model('DB')-E<gt>resultset('Books')>. The
+B<TIP>: You may see the C<$c-E<gt>model('DB::Book')> un-commented
+above written as C<$c-E<gt>model('DB')-E<gt>resultset('Book')>. The
two are equivalent. Either way, C<$c-E<gt>model> returns a
L<DBIx::Class::ResultSet|DBIx::Class::ResultSet> which handles queries
against the database and iterating over the set of results that is
things like filtering and sorting the results. For example, the
following could be used to sort the results by descending title:
- $c->model('DB::Books')->search({}, {order_by => 'title DESC'});
+ $c->model('DB::Book')->search({}, {order_by => 'title DESC'});
Some other examples are provided in
L<DBIx::Class::Manual::Cookbook/Complex WHERE clauses>, with
[debug] Statistics enabled
[debug] Loaded plugins:
.----------------------------------------------------------------------------.
- | Catalyst::Plugin::ConfigLoader 0.20 |
- | Catalyst::Plugin::StackTrace 0.08 |
- | Catalyst::Plugin::Static::Simple 0.20 |
+ | Catalyst::Plugin::ConfigLoader 0.23 |
+ | Catalyst::Plugin::StackTrace 0.10 |
+ | Catalyst::Plugin::Static::Simple 0.21 |
'----------------------------------------------------------------------------'
[debug] Loaded dispatcher "Catalyst::Dispatcher"
| MyApp::Controller::Books | instance |
| MyApp::Controller::Root | instance |
| MyApp::Model::DB | instance |
- | MyApp::Model::DB::Authors | class |
- | MyApp::Model::DB::BookAuthors | class |
- | MyApp::Model::DB::Books | class |
+ | MyApp::Model::DB::Author | class |
+ | MyApp::Model::DB::Book | class |
+ | MyApp::Model::DB::BookAuthor | class |
| MyApp::View::TT | instance |
'-----------------------------------------------------------------+----------'
| /books/list | /books/list |
'-------------------------------------+--------------------------------------'
- [info] MyApp powered by Catalyst 5.71000
+ [info] MyApp powered by Catalyst 5.80003
You can connect to your server at http://debian:3000
B<NOTE:> Be sure you run the C<script/myapp_server.pl> command from
Catalyst::Model::DBIC::Schema dynamically created three model classes,
one to represent each of the three tables in our database
-(C<MyApp::Model::DB::Authors>, C<MyApp::Model::DB::BookAuthors>,
-and C<MyApp::Model::DB::Books>).
+(C<MyApp::Model::DB::Author>, C<MyApp::Model::DB::BookAuthor>,
+and C<MyApp::Model::DB::Book>).
=item *
Result Class files. (Note: if you are using a database other than
SQLite, such as PostgreSQL, then the relationship could have been
automatically placed in the Result Class files. If so, you can skip
-this step.) First edit C<lib/MyApp/Schema/Result/Books.pm> and add the
+this step.) First edit C<lib/MyApp/Schema/Result/Book.pm> and add the
following text below the C<# You can replace this text...> comment:
#
# 1) Name of relationship, DBIC will create accessor with this name
# 2) Name of the model class referenced by this relationship
# 3) Column name in *foreign* table (aka, foreign key in peer table)
- __PACKAGE__->has_many(book_authors => 'MyApp::Schema::Result::BookAuthors', 'book_id');
+ __PACKAGE__->has_many(book_author => 'MyApp::Schema::Result::BookAuthor', 'book_id');
# many_to_many():
# args:
# 2) Name of has_many() relationship this many_to_many() is shortcut for
# 3) Name of belongs_to() relationship in model class of has_many() above
# You must already have the has_many() defined to use a many_to_many().
- __PACKAGE__->many_to_many(authors => 'book_authors', 'author');
+ __PACKAGE__->many_to_many(author => 'book_author', 'author');
B<Note:> Be careful to put this code I<above> the C<1;> at the end of the
a statement that evaluates to C<true>. This is customarily done with
C<1;> on a line by itself.
-C<Important Note:> Although this tutorial uses plural names for both
-the names of the SQL tables and therefore the Result Classes (after
-all, C<Schema::Loader> automatically named the Result Classes from the
-names of the SQL tables it found), DBIx::Class users prefer singular
-names for these items. B<Please try to use singular table and DBIC
-model/Result Class names in your applications.> This tutorial will
-migrate to singular names as soon as possible (patches welcomed).
-B<Note that while singular is preferred for the DBIC model, plural is
-perfectly acceptable for the names of the controller classes.> After
-all, the C<Books.pm> controller operates on multiple books.
-
This code defines both a C<has_many> and a C<many_to_many>
relationship. The C<many_to_many> relationship is optional, but it
makes it easier to map a book to its collection of authors. Without
-it, we would have to "walk" though the C<book_authors> table as in
-C<$book-E<gt>book_authors-E<gt>first-E<gt>author-E<gt>last_name> (we
+it, we would have to "walk" though the C<book_author> table as in
+C<$book-E<gt>book_author-E<gt>first-E<gt>author-E<gt>last_name> (we
will see examples on how to use DBIx::Class objects in your code soon,
-but note that because C<$book-E<gt>book_authors> can return multiple
+but note that because C<$book-E<gt>book_author> can return multiple
authors, we have to use C<first> to display a single author).
-C<many_to_many> allows us to use the shorter C<$book-E<gt>authors-
+C<many_to_many> allows us to use the shorter C<$book-E<gt>author-
E<gt>first-E<gt>last_name>. Note that you cannot define a
C<many_to_many> relationship without also having the C<has_many>
relationship in place.
-Then edit C<lib/MyApp/Schema/Result/Authors.pm> and add relationship
+Then edit C<lib/MyApp/Schema/Result/Author.pm> and add relationship
information as follows (again, be careful to put in above the C<1;> but
below the C<# DO NOT MODIFY THIS OR ANYTHING ABOVE!> comment):
# 1) Name of relationship, DBIC will create an accessor with this name
# 2) Name of the model class referenced by this relationship
# 3) Column name in *foreign* table (aka, foreign key in peer table)
- __PACKAGE__->has_many(book_author => 'MyApp::Schema::Result::BookAuthors', 'author_id');
+ __PACKAGE__->has_many(book_author => 'MyApp::Schema::Result::BookAuthor', 'author_id');
# many_to_many():
# args:
# 2) Name of has_many() relationship this many_to_many() is shortcut for
# 3) Name of belongs_to() relationship in model class of has_many() above
# You must already have the has_many() defined to use a many_to_many().
- __PACKAGE__->many_to_many(books => 'book_author', 'book');
+ __PACKAGE__->many_to_many(book => 'book_author', 'book');
Finally, do the same for the "join table,"
-C<lib/MyApp/Schema/Result/BookAuthors.pm>:
+C<lib/MyApp/Schema/Result/BookAuthor.pm>:
#
# Set relationships:
# 1) Name of relationship, DBIC will create accessor with this name
# 2) Name of the model class referenced by this relationship
# 3) Column name in *this* table
- __PACKAGE__->belongs_to(book => 'MyApp::Schema::Result::Books', 'book_id');
+ __PACKAGE__->belongs_to(book => 'MyApp::Schema::Result::Book', 'book_id');
# belongs_to():
# args:
# 1) Name of relationship, DBIC will create accessor with this name
# 2) Name of the model class referenced by this relationship
# 3) Column name in *this* table
- __PACKAGE__->belongs_to(author => 'MyApp::Schema::Result::Authors', 'author_id');
+ __PACKAGE__->belongs_to(author => 'MyApp::Schema::Result::Author', 'author_id');
=head2 Run The Application
Let's add a new column to our book list page that takes advantage of
the relationship information we manually added to our schema files in
the previous section. Edit C<root/src/books/list.tt2> and replace
-the "empty" tabase cell with the following:
+the "empty" table cell "<td></td>" with the following:
...
<td>
DBIx::Class):
SELECT me.id, me.title, me.rating FROM books me:
- SELECT author.id, author.first_name, author.last_name FROM book_authors me
- JOIN authors author ON ( author.id = me.author_id ) WHERE ( me.book_id = ? ): '1'
- SELECT author.id, author.first_name, author.last_name FROM book_authors me
- JOIN authors author ON ( author.id = me.author_id ) WHERE ( me.book_id = ? ): '2'
- SELECT author.id, author.first_name, author.last_name FROM book_authors me
- JOIN authors author ON ( author.id = me.author_id ) WHERE ( me.book_id = ? ): '3'
- SELECT author.id, author.first_name, author.last_name FROM book_authors me
- JOIN authors author ON ( author.id = me.author_id ) WHERE ( me.book_id = ? ): '4'
- SELECT author.id, author.first_name, author.last_name FROM book_authors me
- JOIN authors author ON ( author.id = me.author_id ) WHERE ( me.book_id = ? ): '5'
+ SELECT author.id, author.first_name, author.last_name FROM book_author me
+ JOIN author author ON ( author.id = me.author_id ) WHERE ( me.book_id = ? ): '1'
+ SELECT author.id, author.first_name, author.last_name FROM book_author me
+ JOIN author author ON ( author.id = me.author_id ) WHERE ( me.book_id = ? ): '2'
+ SELECT author.id, author.first_name, author.last_name FROM book_author me
+ JOIN author author ON ( author.id = me.author_id ) WHERE ( me.book_id = ? ): '3'
+ SELECT author.id, author.first_name, author.last_name FROM book_author me
+ JOIN author author ON ( author.id = me.author_id ) WHERE ( me.book_id = ? ): '4'
+ SELECT author.id, author.first_name, author.last_name FROM book_author me
+ JOIN author author ON ( author.id = me.author_id ) WHERE ( me.book_id = ? ): '5'
Also note in C<root/src/books/list.tt2> that we are using "| html", a
type of TT filter, to escape characters such as E<lt> and E<gt> to <
# Retrieve all of the book records as book model objects and store in the
# stash where they can be accessed by the TT template
- $c->stash->{books} = [$c->model('DB::Books')->all];
+ $c->stash->{books} = [$c->model('DB::Book')->all];
# Set the TT template to use. You will almost always want to do this
# in your action methods (actions methods respond to user input in
the C<$c-E<gt>detach> mechanisms (these are discussed in Chapter 2 and
Chapter 9 of the Tutorial).
+B<IMPORTANT:> Make sure that you do NOT skip the following section
+before continuing to the next chapter 4 Basic CRUD.
=head2 Return To A Manually Specified Template
projects / catagits/Catalyst-Manual.git / blobdiff