CatalystX::Controller::ExtJS::REST - RESTful interface to dbic objects

NAME

CatalystX::Controller::ExtJS::REST - RESTful interface to dbic objects

VERSION

version 1.120000

SYNOPSIS

  package MyApp::Controller::User;
  use base qw(CatalystX::Controller::ExtJS::REST);
  
  __PACKAGE__->config({ ... });
  1;
  
  # set the Accept header to 'application/json' globally
  
  Ext.Ajax.defaultHeaders = {
   'Accept': 'application/json'
  };

DESCRIPTION

This controller will make CRUD operations with ExtJS dead simple. Using REST you can update, create, remove, read and list objects which are retrieved via the DBIx::Class manpage.

USAGE

Set-up Form Configuration

To use this controller, you need to set up at least one configuration file per controller

If you create a controller MyApp::Controller::User:

  package MyApp::Controller::User;
  
  use Moose;
  extends 'CatalystX::Controller::ExtJS::REST';
  
  1;

You also need to create a file root/forms/user.yml. To a more fine grained control over object creation, deletion, update or listing, you have to create some more files.

  root/
       forms/
             user.yml
             user_get.yml
             user_post.yml
             user_put.yml
       lists/
             user.yml

Only root/forms/user.yml is required. All other files are optional. If ExtJS issues a GET request, this controller will first try to find the file root/forms/user_get.yml. If this file does not exist, it will fall back to the so called base file root/forms/user.yml.

This controller tries to guess the correct model and resultset. The model defaults to DBIC and the resultset is derived from the name of the controller. In this example the controller uses the resultset $c->model('DBIC::User').

You can override these values in the form config files:

  ---
    model_config:
      resultset: User
      schema: DBIC
    elements:
      - name: username
      - name: password
      - name: name
      - name: forename
      
  # root/forms/user_put.yml
  # make username and password required an object is created
  ---
    load_config_file: root/forms/user.yml
        constraints:
          - type: Required
            name: username
          - type: Required
            name: password

Now you can fire up your Catalyst app and you should see two new chained actions:

  Loaded Chained actions:
  ...
  | /users/...                          | /user/list
  | /user/...                           | /user/object

Accessing objects

To access an object, simply request the controller's url with the desired method. A POST request to /user will create a new user object. The response will include the id of the new object. You can get the object by requesting /user/$id via GET or remove it by using the DELETE method.

To update an object, use PUT. PUT is special since it also allows for partial submits. This means, that the object is loaded into the form before the request parameters are applied to it. You only need to send changed columns to the server.

Accessing a list of objects

You can access http://localhost:3000/users or http://localhost:3000/user to get a list of users, which can be used to populate an ExtJS store. If you access this URL with your browser you'll get a HTML representation of all users. If you access using a XMLHttpRequest using ExtJS the returned value will be a valid JSON string. Listing objects is very flexible and can easily be extended. There is also a built-in validation for query parameters. By default the following parameters are checked for sane defaults:

You can extend the validation of parameters by providing an additional file. Place it in root/lists/ and add the suffix _options (e. g. root/lists/user_options.yml). You can overwrite or extend the validation configuration there.

Any more attributes you add to the url will result in a call to the corresponding resultset.

  # http://localhost:3000/users/active/
  
  $c->model('DBIC::Users')->active($c)->all;

As you can see, the Catalyst context object is passed as first parameter. You can even supply arguments to that method using a comma separated list:

  # http://localhost:3000/users/active,arg1,arg2/
  
  $c->model('DBIC::Users')->active($c, 'arg1', 'arg2')->all;

You can chain those method calls to any length. Though, you cannot access resultset method which are inherited from the DBIx::Class::ResultSet manpage. This is a security restriction because an attacker could call http://localhost:3000/users/delete which will lead to $c->model('DBIC::Users')->delete. This would remove all rows from DBIC::Users!

To define a default resultset method which gets called every time the controller hits the result table, set:

  __PACKAGE__->config({default_rs_method => 'restrict'});

This will lead to the following chain:

  # http://localhost:3000/users/active,arg1,arg2/
  
  $c->model('DBIC::Users')->restrict($c)->active($c, 'arg1', 'arg2')->all;

  # same for GET, POST and PUT
  # http://localhost:3000/user/1234
  
  $c->model('DBIC::Users')->restrict($c)->find(1234);

The default_rs_method defaults to the value of default_rs_method. If it is not set by the configuration, this controller tries to call extjs_rest_$class (i.e. extjs_rest_user).

Handling Uploads

This module handles your uploads. If there is an upload and the name of that field exists in you form config, the column is set to an the IO::File manpage object. You need to handle this on the model side because storing a filehandle will most likely fail.

Fortunately, there are modules out there which can help you with that. Have a look at the DBIx::Class::InflateColumn::FS manpage. Don't use the DBIx::Class:InflateColumn::File manpage because it is deprecated and broken. If you need a more advanced processing of uploaded files, don't hesitate and overwrite handle_uploads.

CONFIGURATION

Local configuration:

  __PACKAGE__->config({ ... });

Global configuration for all controllers which use CatalystX::Controller::ExtJS::REST:

  MyApp->config( {
    CatalystX::Controller::ExtJS::REST => 
      { key => value }
  } );

find_method

The method to call on the resultset to get an existing row object. This can be set to the name of a custom function function which is defined with the (custom) resultset class. It needs to take the primary key as first parameter.

Defaults to find.

default_rs_method

This resultset method is called on every request. This is useful if you want to restrict the resultset, e. g. only find objects which are associated to the current user.

Nothing is called if the specified method does not exist.

This defaults to extjs_rest_[controller namespace].

A controller MyApp::Controller::User expects a resultset method extjs_rest_user.

root_property

Set the root property used by list, update and create which will contain the data. Defaults to data.

context_stash

To allow your form validation packages, etc, access to the catalyst context, a weakened reference of the context is copied into the form's stash.

    $form->stash->{context};

This setting allows you to change the key name used in the form stash.

Default value: context

form_base_path

Defaults to root/forms

list_base_path

Defaults to root/lists

no_list_metadata

If set to a true value there will be no meta data send with lists.

Defaults to undef. That means the metaData hash will be send by default.

model_config

schema

Defaults to DBIC

resultset

Defaults to default_resultset

namespace

Defaults to namespace in the Catalyst::Controller manpage

list_namespace

Defaults to the plural form of namespace. If this is the same as namespace list_ is prepended.

LIMITATIONS

This module is limited to the HTML::FormFu manpage as form processing engine, the DBIx::Class manpage as ORM and Catalyst as web application framework.

PUBLIC ATTRIBUTES

To change the default value of an attribute, either set it as default value

  package MyApp::Controller::MyController;
  use Moose;
  extends 'CatalystX::Controller::ExtJS::REST';
  
  has '+default_result' => ( default => 'MyUser' );

use the config

  __PACKAGE__->config( default_result => 'MyUser' );

or overwrite the builder

  sub _build_default_result { return 'MyUser' };

default_resultset

Determines the default name of the resultset class from the Model / View or Controller class if the forms contains no <model_config/resultset> config value. Defaults to the class name of the controller.

list_base_path

Returns the path in which form config files for grids will be searched.

list_base_file

Returns the path to the specific form config file for grids or the default form config file if the specfic one can not be found.

path_to_forms

Returns the path to the specific form config file or the default form config file if the specfic one can not be found.

form_base_path

base_path

Returns the path in which form config files will be searched.

form_base_file

base_file

Returns the path to the default form config file.

PUBLIC METHODS

get_form

Returns a new the HTML::FormFu::ExtJS manpage class, sets the model config options and the request type to Catalyst.

list

List Action which returns the data for a ExtJS grid.

handle_uploads

Handles uploaded files by assigning the filehandle to the column accessor of the DBIC row object.

As an upload field is a regular field it gets set twice. First the filename is set and $row->update is called. This is entirely handled by the HTML::FormFu::Model::DBIC manpage. After that handle_uploads is called which sets the value of a upload field to the corresponding the IO::File manpage object. Make sure you test for that, if you plan to inflate such a column.

If you want to handle uploads yourself, overwrite handle_uploads

  sub handle_uploads {
      my ($self, $c, $row) = @_;
      if(my $file = c->req->uploads->{upload}) {
          $file->copy_to('yourdestination/'.$filename);
          $row->upload($file->filename);
      }
  }

However, this should to be part of the model.

Since you cannot upload files with an XMLHttpRequest, ExtJS creates an iframe and issues a POST request in there. If you need to make a PUT request you have to tunnel the desired method using a hidden field, by using the params config option of Ext.form.Action.Submit or extraParams in Ext.Ajax.request. The name of that parameter has to be x-tunneled-method.

Make sure you do not include a file field in your GET form definition. It will cause a security error in your browser because it is not allowed set the value of a file field.

object

REST Action which returns works with single model entites.

object_PUT

REST Action to update a single model entity with a PUT request.

object_POST

REST Action to create a single model entity with a POST request.

object_PUT_or_POST

Internal method for REST Actions to handle the update of single model entity with PUT or POST requests.

This method is called before the form is being processed. To add or remove form elements dynamically, this would be the right place.

object_GET

REST Action to get the data of a single model entity with a GET request.

object_DELETE

REST Action to delete a single model entity with a DELETE request.

PRIVATE ATTRIBUTES

_extjs_config

This attribute holds the configuration for the controller. It is created by merging by __PACKAGE__->config with the default values.

PRIVATE METHODS

These methods are private. Please don't overwrite those unless you know what you are doing.

begin

Run this code before any action in this controller. It sets the ActionClass to the CatalystX::Action::ExtJS::Deserialize manpage. This ActionClass makes sure that no deserialization happens if the body's content is a file upload.

end

If the request contains a file upload field, extjs expects the json response to be serialized and returned in a document with the Content-type set to text/html.

_parse_NSPathPart_attr

_parse_NSListPathPart_attr

CONTRIBUTORS

  Mario Minati

AUTHOR

Moritz Onken <onken@netcubed.de>

COPYRIGHT AND LICENSE

This software is Copyright (c) 2010 by Moritz Onken.

This is free software, licensed under:

  The (three-clause) BSD License
 CatalystX::Controller::ExtJS::REST - RESTful interface to dbic objects