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NAME

Maypole - MVC web application framework

SYNOPSIS

See Maypole::Application.

DESCRIPTION

This documents the Maypole request object. See the Maypole::Manual, for a detailed guide to using Maypole.

Maypole is a Perl web application framework to Java's struts. It is essentially completely abstracted, and so doesn't know anything about how to talk to the outside world.

To use it, you need to create a package which represents your entire application. In our example above, this is the BeerDB package.

This needs to first use Maypole::Application which will make your package inherit from the appropriate platform driver such as Apache::MVC or CGI::Maypole, and then call setup. This sets up the model classes and configures your application. The default model class for Maypole uses Class::DBI to map a database to classes, but this can be changed by altering configuration. (Before calling setup.)

CLASS METHODS

config

Returns the Maypole::Config object

setup

    My::App->setup($data_source, $user, $password, \%attr);

Initialise the maypole application and model classes. Your application should call this after setting configuration via "config"

init

You should not call this directly, but you may wish to override this to add application-specific initialisation.

view_object

Get/set the Maypole::View object

debug

    sub My::App::debug {1}

Returns the debugging flag. Override this in your application class to enable/disable debugging.

INSTANCE METHODS

parse_location

Turns the backend request (e.g. Apache::MVC, Maypole, CGI) into a Maypole request. It does this by setting the path, and invoking parse_path and parse_args.

You should only need to define this method if you are writing a new Maypole backend.

path

Returns the request path

parse_path

Parses the request path and sets the args, action and table properties

table

The table part of the Maypole request path

action

The action part of the Maypole request path

args

A list of remaining parts of the request path after table and action have been removed

headers_in

A Maypole::Headers object containing HTTP headers for the request

headers_out

A HTTP::Headers object that contains HTTP headers for the output

parse_args

Turns post data and query string paramaters into a hash of params.

You should only need to define this method if you are writing a new Maypole backend.

param

An accessor for request parameters. It behaves similarly to CGI::param() for accessing CGI parameters.

params

Returns a hash of request parameters. The source of the parameters may vary depending on the Maypole backend, but they are usually populated from request query string and POST data.

Note: Where muliple values of a parameter were supplied, the params value will be an array reference.

get_template_root

Implementation-specific path to template root.

You should only need to define this method if you are writing a new Maypole backend. Otherwise, see "template_root" in Maypole::Config

get_request

You should only need to define this method if you are writing a new Maypole backend. It should return something that looks like an Apache or CGI request object, it defaults to blank.

is_applicable

Returns a Maypole::Constant to indicate whether the request is valid.

The default implementation checks that $r->table is publicly accessible and that the model class is configured to handle the $r->action

authenticate

Returns a Maypole::Constant to indicate whether the user is authenticated for the Maypole request.

The default implementation returns OK

model_class

Returns the perl package name that will serve as the model for the request. It corresponds to the request table attribute.

additional_data

Called before the model processes the request, this method gives you a chance to do some processing for each request, for example, manipulating template_args.

objects

Get/set a list of model objects. The objects will be accessible in the view templates.

If the first item in $r->args can be retrieve()d by the model class, it will be removed from args and the retrieved object will be added to the objects list. See Maypole::Model for more information.

template_args

    $r->template_args->{foo} = 'bar';

Get/set a hash of template variables.

template

Get/set the template to be used by the view. By default, it returns $r->action

exception

This method is called if any exceptions are raised during the authentication or model/view processing. It should accept the exception as a parameter and return a Maypole::Constant to indicate whether the request should continue to be processed.

error

Get/set a request error

output

Get/set the response output. This is usually populated by the view class. You can skip view processing by setting the output.

document_encoding

Get/set the output encoding. Default: utf-8.

content_type

Get/set the output content type. Default: text/html

send_output

Sends the output and additional headers to the user.

call_authenticate

This method first checks if the relevant model class can authenticate the user, or falls back to the default authenticate method of your Maypole application.

call_exception

This model is called to catch exceptions, first after authenticate, then after processing the model class, and finally to check for exceptions from the view class.

This method first checks if the relevant model class can handle exceptions the user, or falls back to the default exception method of your Maypole application.

handler

This method sets up the class if it's not done yet, sets some defaults and leaves the dirty work to handler_guts.

handler_guts

This is the core of maypole. You don't want to know.

SEE ALSO

There's more documentation, examples, and a information on our mailing lists at the Maypole web site:

http://maypole.perl.org/

Maypole::Application, Apache::MVC, CGI::Maypole.

AUTHOR

Maypole is currently maintained by Simon Flack simonflk#cpan.org

AUTHOR EMERITUS

Simon Cozens, simon#cpan.org

Sebastian Riedel, sri#oook.de maintained Maypole from 1.99_01 to 2.04

THANKS TO

Sebastian Riedel, Danijel Milicevic, Dave Slack, Jesse Sheidlower, Jody Belka, Marcus Ramberg, Mickael Joanne, Randal Schwartz, Simon Flack, Steve Simms, Veljko Vidovic and all the others who've helped.

LICENSE

You may distribute this code under the same terms as Perl itself.