php.activerecord

h2. Utilities

*(#topic-list) "Delegators":/projects/main/wiki/Utilities#delegators

* "Attribute Setters":/projects/main/wiki/Utilities#attribute-setters

* "Attribute Getters":/projects/main/wiki/Utilities#attribute-getters

* "Aliased attributes":/projects/main/wiki/Utilities#aliased-attributes

* "Protected attributes":/projects/main/wiki/Utilities#protected-attributes

* "Accessible attributes":/projects/main/wiki/Utilities#accessible-attributes

* "Serialization":/projects/main/wiki/Utilities#serialization

ActiveRecord offers numerous ways to make your life easier by adding some interesting features to your models.

h4(#delegators). Delegators

This is similar to "attribute aliasing":/projects/main/wiki/Utilities#aliased-attributes, except that it works via your associations. You can alias an attribute on your model to use a particular attribute on an association. Let's take a look.

<pre class="code"><code class="php">

class Person extends ActiveRecord\Model {

  static $belongs_to = array(array('venue'),array('host'));

  static $delegate = array(

    array('name', 'state', 'to' => 'venue'),

    array('name', 'to' => 'host', 'prefix' => 'host'));

}

$person = Person::first();

$person->state     # same as calling $person->venue->state

$person->name      # same as calling $person->venue->name

$person->host_name # same as calling $person->host->name

</code></pre>

h4(#attribute-setters). Attribute setters

Setters allow you to define custom methods for assigning a value to one of your attributes. This means you can intercept the assign process and filter/modify the data to your needs. This is helpful in a situation such as encrypting user passwords. Normally, you define a setter which does not carry the same name as your attribute, but you can set your attribute inside of the method. In the example below, *$user->password* is a virtual attribute: if you try to read/access the attribute instead of assign, an "UndefinedPropertyException":/docs/ActiveRecord/UndefinedPropertyException will be thrown.

<pre class="code"><code class="php">

class User extends ActiveRecord\Model {

  static $setters = array('password','second_custom_setter');

  # A setter method must have set_ prepended to its name to qualify.

  # $this->encrypted_password is the actual attribute for this model.

  public function set_password($plaintext) {

    $this->encrypted_password = md5($plaintext);

  }

}

$user = new User;

$user->password = 'plaintext';  # will call $user->set_password('plaintext')

# if you did an echo $user->password you would get an UndefinedPropertyException

</code></pre>

If you define a custom setter with the same name as an attribute then you will need to use "assign_attribute()":/docs/ActiveRecord/Model#methodassign_attribute to assign the value to the attribute. This is necessary due to the way "Model::__set()":/docs/ActiveRecord/Model#method__set works. For example, assume 'name' is a field on the table and we're defining a custom setter called 'name':

<pre class="code"><code class="php">

class User extends ActiveRecord\Model {

  static $setters = array('name');

  # INCORRECT:

  # function set_name($name) {

  #   $this->name = strtoupper($name);

  # }

  public function set_name($name) {

    $this->assign_attribute('name',strtoupper($name));

  }

}

$user = new User;

$user->name = 'bob';

echo $user->name; # => BOB

</code></pre>

h4(#attribute-getters). Attribute getters

Getters allow you to intercept attribute/property value retrieval on your models. They are defined in a similar manner to setters. See "Model::$getters":/docs/ActiveRecord/Model#var$getters for details.

h4(#aliased-attributes). Aliased attributes

This option is fairly straight-forward. An aliased attribute allows you to set/get the attribute via a different name. This comes in handy when you have terrible field names like field_one, field_two, or for legacy tables.

<pre class="code"><code class="php">

class Person extends ActiveRecord\Model {

  static $alias_attribute = array(

    'first_name' => 'person_first_name',

    'last_name' => 'person_last_name');

}

$person = Person::first();

echo $person->person_first_name; # => Jax

$person->first_name = 'Tito';

echo $person->first_name; # => Tito

echo $person->person_first_name; # => Tito

</code></pre>

h4(#protected-attributes). Protected attributes

Blacklist of attributes that cannot be mass-assigned. Protecting these attributes allows you to avoid security problems where a malicious user may try to create additional post values. This is the opposite of "accessible attributes":/projects/main/wiki/Utilities#accessible-attributes.

<pre class="code"><code class="php">

class User extends ActiveRecord\Model {

  static $attr_protected = array('admin');

}

$attributes = array('first_name' => 'Tito','admin' => 1);

$user = new User($attributes);

echo $user->first_name; # => Tito

echo $user->admin; # => null

# now no one can fake post values and make themselves an admin against your will!

</code></pre>

h4(#accessible-attributes). Accessible attributes

Whitelist of attributes that are checked from mass-assignment calls such as constructing a model or using "Model::update_attributes()":/docs/ActiveRecord/Model#methodupdate_attributes. This is the opposite of "protected attributes":/projects/main/wiki/Utilities#protected-attributes. Accessible attributes can also be used as a security measure against fake post values, except that it is often more pragmatic because it is a whitelist approach.

<pre class="code"><code class="php">

class User extends ActiveRecord\Model {

  static $attr_accessible = array('first_name');

}

$attributes = array('first_name' => 'Tito','last_name' => 'J.','admin' => 1);

$user = new User($attributes);

echo $person->last_name; # => null

echo $person->admin; # => null

echo $person->first_name; # => Tito

# first_name is the only attribute that can be mass-assigned, so the other 2 are null

</code></pre>

h4(#serialization). Serialization

This is not the normal kind of PHP serialization you are used to. This will not serialize your entire object; however, it will serialize the attributes of your model to either an xml or a json representation. An options array can take the following parameters:

*only*: a string or array of attributes to be included.

*exclude*: a string or array of attributes to be excluded.

*methods*: a string or array of methods to invoke. The method's name will be used as a key for the final attributes array along with the method's returned value

*include*: a string or array of associated models to include in the final serialized product.

*skip_instruct*: set to true to skip the <?xml ...?> declaration.

Below only includes "Model::to_json()":/docs/ActiveRecord/Model#methodto_json examples; however, you can use all of the examples with "Model::to_xml()":/docs/ActiveRecord/Model#methodto_xml

<pre class="code"><code class="php">

class User extends ActiveRecord\Model {

  static $has_many = array(array('orders'));

  public function name() {

    return $this->first_name .' '. $this->last_name;

  }

}

# assume these fields are on our `users` table:

# id, first_name, last_name, email, social_security, phone_number

$user = User::first();

# json should only contain id and email

$json = $user->to_json(array(

  'only' => array('id', 'email')

));

echo $json; # => {"id":1,"email":"[email protected]"}

# limit via exclusion (here we use a string, but an array can be passed)

$json = $user->to_json(array(

  'except' => 'social_security'

));

echo $json; # => {"id":1,"first_name":"George","last_name":"Bush",

            #     "email":"[email protected]","phone_number":"555-5555"}

# call $user->name() and the returned value will be in our json

$json = $user->to_json(array(

  'only' => array('email', 'name'),

  'methods' => 'name'

));

echo $json; # => {"name":"George Bush","email":"[email protected]"}

# call $user->name() and the returned value will be in our json

$json = $user->to_json(array(

  'only' => array('email', 'name'),

  'methods' => 'name'

));

# include the orders association

$json = $user->to_json(array(

  'include' => array('orders')

));

# you can nest includes .. here orders also has a payments association

$json = $user->to_json(array(

  'include' => array('orders' => array('except' => 'id', 'include' => 'payments')

));

</code></pre>

DateTime fields are serialized to "ISO8601":http://www.php.net/manual/en/class.datetime.php#datetime.constants.iso8601 format by default. If you need to change this call the "set_date_format()":/docs/ActiveRecord/Config#methodset_date_format method in your configuration block.

<pre class="code"><code class="php">

ActiveRecord\Config::initialize(function($cfg)

{

  # set the date format for serialization

  $cfg->set_date_format('Y-m-d H:i:s');

  # your other configuration stuff

  ...

});

</code></pre>