application. Given that many other documents cover this subject in
detail, MVC will not be discussed in depth here (for an excellent
introduction to MVC and general Catalyst concepts, please see
-L<Catalyst::Manual::About|Catalyst::Manual::About>). In short:
+L<Catalyst::Manual::About>). In short:
=over 4
You can checkout the source code for this example from the catalyst
subversion repository as per the instructions in
-L<Catalyst::Manual::Tutorial::01_Intro|Catalyst::Manual::Tutorial::01_Intro>.
+L<Catalyst::Manual::Tutorial::01_Intro>.
=head1 CREATE A CATALYST PROJECT
Catalyst provides a number of helper scripts that can be used to quickly
flesh out the basic structure of your application. All Catalyst projects
-begin with the C<catalyst.pl> helper (see
-L<Catalyst::Helper|Catalyst::Helper> for more information on helpers).
+begin with the F<catalyst.pl> helper (see
+L<Catalyst::Helper> for more information on helpers).
Also note that as of Catalyst 5.7000, you will not have the helper
-scripts unless you install both L<Catalyst::Runtime|Catalyst::Runtime>
-and L<Catalyst::Devel|Catalyst::Devel>.
+scripts unless you install both L<Catalyst::Runtime>
+and L<Catalyst::Devel>.
-In this first chapter of the tutorial, use the Catalyst C<catalyst.pl>
+In this first chapter of the tutorial, use the Catalyst F<catalyst.pl>
script to initialize the framework for an application called C<Hello>:
$ catalyst.pl Hello
from the end of the "catalyst.pl" command and simply use
"catalyst Hello".
-The C<catalyst.pl> helper script will display the names of the
+The F<catalyst.pl> helper script will display the names of the
directories and files it creates:
Changes # Record of application changes
lib # Lib directory for your app's Perl modules
Hello # Application main code directory
- Controller # Directory for Controller modules
+ Controller # Directory for Controller modules
Model # Directory for Models
View # Directory for Views
Hello.pm # Base application module
hello_server.pl # The normal development server
hello_test.pl # Test your app from the command line
t # Directory for tests
- 01app.t # Test scaffold
- 02pod.t
- 03podcoverage.t
+ 01app.t # Test scaffold
+ 02pod.t
+ 03podcoverage.t
Catalyst will "auto-discover" modules in the Controller, Model, and View
-directories. When you use the hello_create.pl script it will create Perl
+directories. When you use the F<hello_create.pl> script it will create Perl
module scaffolds in those directories, plus test files in the "t"
directory. The default location for templates is in the "root"
directory. The scripts in the script directory will always start with
[debug] Statistics enabled
[debug] Loaded plugins:
.----------------------------------------------------------------------------.
- | Catalyst::Plugin::ConfigLoader 0.27 |
+ | Catalyst::Plugin::ConfigLoader 0.30 |
'----------------------------------------------------------------------------'
-
+
[debug] Loaded dispatcher "Catalyst::Dispatcher"
- [debug] Loaded engine "Catalyst::Engine::HTTP"
- [debug] Found home "/home/me/Hello"
- [debug] Loaded Config "/home/me/Hello/hello.conf"
+ [debug] Loaded engine "Catalyst::Engine"
+ [debug] Found home "/home/catalyst/Hello"
+ [debug] Loaded Config "/home/catalyst/Hello/hello.conf"
[debug] Loaded components:
.-----------------------------------------------------------------+----------.
| Class | Type |
+-----------------------------------------------------------------+----------+
| Hello::Controller::Root | instance |
'-----------------------------------------------------------------+----------'
-
+
[debug] Loaded Private actions:
.----------------------+--------------------------------------+--------------.
| Private | Class | Method |
| /end | Hello::Controller::Root | end |
| /index | Hello::Controller::Root | index |
'----------------------+--------------------------------------+--------------'
-
+
[debug] Loaded Path actions:
.-------------------------------------+--------------------------------------.
| Path | Private |
| / | /index |
| / | /default |
'-------------------------------------+--------------------------------------'
-
- [info] Hello powered by Catalyst 5.80020
- You can connect to your server at http://debian:3000
+
+ [info] Hello powered by Catalyst 5.90002
+ HTTP::Server::PSGI: Accepting connections at http://0:3000/
Point your web browser to L<http://localhost:3000> (substituting a
different hostname or IP address as appropriate) and you should be
your URL). Information similar to the following should be appended to
the logging output of the development server:
- [info] *** Request 1 (0.001/s) [23194] [Sat Jan 16 11:09:18 2010] ***
- [debug] "GET" request for "/" from "127.0.0.1"
+ [info] Hello powered by Catalyst 5.90002
+ HTTP::Server::PSGI: Accepting connections at http://0:3000/
+ [info] *** Request 1 (0.067/s) [19026] [Tue Aug 30 17:24:32 2011] ***
+ [debug] "GET" request for "/" from "192.168.245.2"
[debug] Path is "/"
- [info] Request took 0.004851s (206.143/s)
+ [debug] Response Code: 200; Content-Type: text/html; charset=utf-8; Content-Length: 5613
+ [info] Request took 0.040895s (24.453/s)
.------------------------------------------------------------+-----------.
| Action | Time |
+------------------------------------------------------------+-----------+
- | /index | 0.000395s |
- | /end | 0.000425s |
+ | /index | 0.000916s |
+ | /end | 0.000877s |
'------------------------------------------------------------+-----------'
B<Note>: Press C<Ctrl-C> to break out of the development server if
=head2 The Simplest Way
The Root.pm controller is a place to put global actions that usually
-execute on the root URL. Open the C<lib/Hello/Controller/Root.pm> file
+execute on the root URL. Open the F<lib/Hello/Controller/Root.pm> file
in your editor. You will see the "index" subroutine, which is
responsible for displaying the welcome screen that you just saw in your
browser.
sub index :Path :Args(0) {
my ( $self, $c ) = @_;
-
+
# Hello World
$c->response->body( $c->welcome_message );
}
The "C<$c>" here refers to the Catalyst context, which is used to access
the Catalyst application. In addition to many other things, the Catalyst
context provides access to "response" and "request" objects. (See
-L<Catalyst|Catalyst>, L<Catalyst::Response|Catalyst::Response>, and
-L<Catalyst::Request|Catalyst::Request>)
+L<Catalyst::Runtime>, L<Catalyst::Response>, and
+L<Catalyst::Request>)
-C<$c-E<gt>response-E<gt>body> sets the HTTP response (see
-L<Catalyst::Response|Catalyst::Response>), while
-C<$c-E<gt>welcome_message> is a special method that returns the welcome
+C<< $c->response->body >> sets the HTTP response (see
+L<Catalyst::Response>), while
+C<< $c->welcome_message >> is a special method that returns the welcome
message that you saw in your browser.
-The ":Path :Args(0)" after the method name are attributes which
+The "C<:Path :Args(0)>" after the method name are attributes which
determine which URLs will be dispatched to this method. (You might see
":Private" if you are using an older version of Catalyst, but using that
with "default" or "index" is currently deprecated. If so, you should
methods. There is a lot of flexibility in specifying which URLs to
match. This particular method will match all URLs, because it doesn't
specify the path (nothing comes after "Path"), but will only accept a
-URL without any args because of the ":Args(0)".
+URL without any args because of the "C<:Args(0)>".
The default is to map URLs to controller names, and because of the way
that Perl handles namespaces through package names, it is simple to
to the package C<Hello::Controller::Admin::Articles>, and the C<create>
method.
-Add the following subroutine to your C<lib/Hello/Controller/Root.pm>
-file:
+While you leave the C<script/hello_server.pl -r> command running the
+development server in one window (don't forget the "-r" at the end!),
+open another window and add the following subroutine to your
+F<lib/Hello/Controller/Root.pm> file:
sub hello :Global {
my ( $self, $c ) = @_;
-
+
$c->response->body("Hello, World!");
}
-Once you restart the server, you will need to use the new address
-L<http://localhost:3000/hello> instead of L<http://localhost:3000/> to see the
-changes.
-
B<TIP>: See Appendix 1 for tips on removing the leading spaces when
cutting and pasting example code from POD-based documents.
-Here you're sending your own string to the webpage.
-
-Save the file, and you should notice the following in your server output:
+Notice in the window running the Development Server that you should
+get output similar to the following:
Saw changes to the following files:
- - /home/me/Hello/lib/Hello/Controller/Root.pm (modify)
-
+ - /home/catalyst/Hello/lib/Hello/Controller/Root.pm (modify)
+
Attempting to restart the server
...
[debug] Loaded Private actions:
| /index | Hello::Controller::Root | index |
| /hello | Hello::Controller::Root | hello |
'----------------------+--------------------------------------+--------------'
-
- [debug] Loaded Path actions:
- .-------------------------------------+--------------------------------------.
- | Path | Private |
- +-------------------------------------+--------------------------------------+
- | / | /index |
- | / | /default |
- | /hello | /hello |
- '-------------------------------------+--------------------------------------'
...
+The development server noticed the change in C<Hello::Controller::Root>
+and automatically restarted itself.
+
Go to L<http://localhost:3000/hello> to see "Hello, World!". Also
notice that the newly defined 'hello' action is listed under "Loaded
Private actions" in the development server debug output.
In the Catalyst world a "View" itself is not a page of XHTML or a
template designed to present a page to a browser. Rather, it is the
-module that determines the I<type> of view -- HTML, pdf, XML, etc. For
-the thing that generates the I<content> of that view (such as the a
-Toolkit Template template file), the actual templates go under the
+module that determines the I<type> of view -- HTML, PDF, XML, etc. For
+the thing that generates the I<content> of that view (such as a
+Template Toolkit template file), the actual templates go under the
"root" directory.
To create a TT view, run:
$ script/hello_create.pl view HTML TT
-This creates the C<lib/Hello/View/HTML.pm> module, which is a subclass
-of C<Catalyst::View::TT>.
+This creates the F<lib/Hello/View/HTML.pm> module, which is a subclass
+of L<Catalyst::View::TT>.
=over 4
The first argument "HTML" tells the script to name the View module "HTML.pm",
which is a commonly used name for TT views. You can name it anything you want,
such as "MyView.pm". If you have more than one view, be sure to set the
-default_view in Hello.pm (See L<Catalyst::View::TT|Catalyst::View::TT> for more
+default_view in Hello.pm (See L<Catalyst::View::TT> for more
details on setting this).
=item *
The final "TT" tells Catalyst the I<type> of the view, with "TT"
-indicating that you want to a Template Toolkit view.
+indicating that you want to use a Template Toolkit view.
=back
-If you look at C<lib/Hello/View/HTML.pm> you will find that it only
+If you look at F<lib/Hello/View/HTML.pm> you will find that it only
contains a config statement to set the TT extension to ".tt".
Now that the HTML.pm "View" exists, Catalyst will autodiscover it and be
able to use it to display the view templates using the "process" method
-that it inherits from the C<Catalyst::View::TT> class.
+that it inherits from the L<Catalyst::View::TT> class.
-Template Toolkit is a very full featured template facility, with
+Template Toolkit is a very full-featured template facility, with
excellent documentation at L<http://template-toolkit.org/>, but since
this is not a TT tutorial, we'll stick to only basic TT usage here (and
explore some of the more common TT features in later chapters of the
tutorial).
-Create a C<root/hello.tt> template file (put it in the C<root> under the
+Create a F<root/hello.tt> template file (put it in the C<root> under the
C<Hello> directory that is the base of your application). Here is a
simple sample:
[% and %] are markers for the TT parts of the template. Inside you can
access Perl variables and classes, and use TT directives. In this case,
we're using a special TT variable that defines the name of the template
-file (C<hello.tt>). The rest of the template is normal HTML.
+file (F<hello.tt>). The rest of the template is normal HTML.
-Change the hello method in C<lib/Hello/Controller/Root.pm> to the
+Change the hello method in F<lib/Hello/Controller/Root.pm> to the
following:
sub hello :Global {
my ( $self, $c ) = @_;
-
+
$c->stash(template => 'hello.tt');
}
-This time, instead of doing C<$c-E<gt>response-E<gt>body()>, you are
+This time, instead of doing C<< $c->response->body() >>, you are
setting the value of the "template" hash key in the Catalyst "stash", an
area for putting information to share with other parts of your
application. The "template" key determines which template will be
displayed at the end of the request cycle. Catalyst controllers have a
default "end" action for all methods which causes the first (or default)
-view to be rendered (unless there's a C<$c-E<gt>response- E<gt>body()>
+view to be rendered (unless there's a C<< $c->response->body() >>
statement). So your template will be magically displayed at the end of
your method.
After saving the file, the development server should automatically
restart (again, the tutorial is written to assume that you are using the
"-r" option -- manually restart it if you aren't), and look at
-L<http://localhost:3000/hello> in your again. You should see the
-template that you just made.
+L<http://localhost:3000/hello> in your web browser again. You should see
+the template that you just created.
B<TIP:> If you keep the server running with "-r" in a "background
-window," don't let that window get totally hidden... if you have an
+window," don't let that window get totally hidden... if you have a
syntax error in your code, the debug server output will contain the
error information.
used previous is becoming more common because it allows you to
set multiple stash variables in one line. For example:
- $c->stash(template => 'hello.tt', foo => 'bar',
+ $c->stash(template => 'hello.tt', foo => 'bar',
another_thing => 1);
You can also set multiple stash values with a hashref:
- $c->stash({template => 'hello.tt', foo => 'bar',
+ $c->stash({template => 'hello.tt', foo => 'bar',
another_thing => 1});
-Any of these formats work, but the C<$c-E<gt>stash(name =E<gt> value);>
+Any of these formats work, but the C<< $c->stash(name => value); >>
style is growing in popularity -- you may wish to use it all the time
(even when you are only setting a single value).
$ script/hello_create.pl controller Site
-This will create a C<lib/Hello/Controller/Site.pm> file (and a test
-file). Bring Site.pm up in your editor, and you can see that there's not
-much there.
+This will create a F<lib/Hello/Controller/Site.pm> file (and a test
+file). If you bring Site.pm up in your editor, you can see that
+there's not much there to see.
-In C<lib/Hello/Controller/Site.pm>, add the following method:
+In F<lib/Hello/Controller/Site.pm>, add the following method:
sub test :Local {
my ( $self, $c ) = @_;
-
+
$c->stash(username => 'John',
template => 'site/test.tt');
}
We've also put the variable "username" into the stash, for use in the
template.
-Make a subdirectory "site" in the "root" directory. Copy the hello.tt
-file into the directory as C<root/site/test.tt>, or create a new
-template file at that location. Include a line like:
+Make a subdirectory "site" in the "root" directory.
- <p>Hello, [% username %]!</p>
+ $ mkdir root/site
+
+Create a new template file in that directory named F<root/site/test.tt>
+and include a line like:
-You should see your test.tt file displayed, including the name "John"
-that you set in the controller.
+ <p>Hello, [% username %]!</p>
Once the server automatically restarts, notice in the server output that
C</site/test> is listed in the Loaded Path actions. Go to
-L<http://localhost:3000/site/test> in your browser.
+L<http://localhost:3000/site/test> in your browser and you should see
+your test.tt file displayed, including the name "John" that you set in
+the controller.
+You can jump to the next chapter of the tutorial here:
+L<More Catalyst Basics|Catalyst::Manual::Tutorial::03_MoreCatalystBasics>
+
=head1 AUTHORS
Gerda Shank, C<gerda.shank@gmail.com>
Feel free to contact the author for any errors or suggestions, but the
best way to report issues is via the CPAN RT Bug system at
-<https://rt.cpan.org/Public/Dist/Display.html?Name=Catalyst-Manual>.
-
-The most recent version of the Catalyst Tutorial can be found at
-L<http://dev.catalyst.perl.org/repos/Catalyst/Catalyst-Manual/5.80/trunk/lib/Catalyst/Manual/Tutorial/>.
+L<https://rt.cpan.org/Public/Dist/Display.html?Name=Catalyst-Manual>.
-Copyright 2006-2010, Kennedy Clark, under the
+Copyright 2006-2011, Kennedy Clark, under the
Creative Commons Attribution Share-Alike License Version 3.0
-(L<http://creativecommons.org/licenses/by-sa/3.0/us/>).
+(L<https://creativecommons.org/licenses/by-sa/3.0/us/>).
projects / catagits/Catalyst-Manual.git / blobdiff