Maypole::Model::Base - Base class for model classes


Maypole::Model::Base - Base class for model classes


This is the base class for Maypole data models. This is an abstract class that defines the interface, and can't be used directly.


This is the engine of this module. Given the request object, it populates all the relevant variables and calls the requested action.

Anyone subclassing this for a different database abstraction mechanism needs to provide the following methods:


    $model->setup_database($config, $namespace, @data)

Uses the user-defined data in @data to specify a database- for example, by passing in a DSN. The model class should open the database, and create a class for each table in the database. These classes will then be adopted. It should also populate $config->tables and $config->classes with the names of the classes and tables respectively. The classes should be placed under the specified namespace. For instance, beer should be mapped to the class BeerDB::Beer.


    $model->class_of($r, $table)

This maps between a table name and its associated class.


This class method is passed a request object and is expected to return an object of the appropriate table class from information stored in the request object.


This class method is passed the name of a model class that represensts a table and allows the master model class to do any set-up required.


This is a list of all the columns in a table. You may also override see also display_columns


This is the name of the table.


If there is an object in $r->objects, then it should be edited with the parameters in $r->params; otherwise, a new object should be created with those parameters, and put back into $r->objects. The template should be changed to view, or edit if there were any errors. A hash of errors will be passed to the template.

The list method should fill $r->objects with all of the objects in the class. You may want to page this using Data::Page or similar.

Empty Action.

Empty Action.

Empty Action, calls list if provided with a table.

Also, see the exported commands in Maypole::Model::CDBI.

Other overrides

Additionally, individual derived model classes may want to override the following methods:


Returns a list of columns to display in the model. By default returns all columns in alphabetical order. Override this in base classes to change ordering, or elect not to show columns.


Same as display_columns, only for listings. Defaults to display_columns


Return a hash mapping column names with human-readable equivalents.


should return true if a certain action is supported, or false otherwise. Defaults to checking if the sub has the :Exported attribute.


Returns the list of attributes defined for a method. Maypole itself only defines the Exported attribute.


This can go either in the master model class or in the individual classes, and returns a list of has-many accessors. A brewery has many beers, so BeerDB::Brewery needs to return beers.

 Maypole::Model::Base - Base class for model classes