The Model class extends the built-in PHP ArrayObject class with internal
data validation and json support.
Models can be used in any context, but they are especially useful in REST API applications, where validating incoming and outgoing data is often time-consuming, inconsistent, error-prone and hard to read/maintain.
Instead of bloating your project with code for validating data, you can let models validate themselves based on their property definition. You just define the properties and constraints of each model in one single place, and then validate model instances throughout your application in a consistent, efficient and clear manner.
Models are similar to database tables, where each model property corresponds to a table column. Install the Model Store package to automatically create database tables based on your models.
You define the model properties and constraints in a separate class for each
model. Each model class must contain the static $properties property and
extend the Model class or a subclass.
In the example below, we create a geo point model with two properties: latitude and longitude. Both properties are required, and they must be floating numbers in the range of -90 to 90 (latitude) and -180 to 180 (longitude).
<?php
use Peroks\Model\Model;
use Peroks\Model\PropertyType;
/**
* The GeoPoint model class.
*
* @property float $latitude The geo point latitude.
* @property float $longitude The geo point longitude.
*/
class GeoPoint extends Model {
/**
* @var array An array of model properties.
*/
protected static array $properties = [
'latitude' => [
'id' => 'latitude',
'name' => 'Latitude',
'desc' => 'The geo point latitude',
'type' => PropertyType::FLOAT,
'required' => true,
'min' => -90,
'max' => 90,
],
'longitude' => [
'id' => 'longitude',
'name' => 'Longitude',
'desc' => 'The geo point longitude',
'type' => PropertyType::FLOAT,
'required' => true,
'min' => -180,
'max' => 180,
],
];
}
You can extend models like any other class. The properties are inherited from the parent classes.
<?php
use Peroks\Model\PropertyType;
/**
* The GeoPoint model with altitue. The altitude is optional.
*
* @property float $altitude The geo point altitude.
*/
class GeoPointWithAltitude extends GeoPoint {
/**
* @var array An array of model properties.
*/
protected static array $properties = [
'altitude' => [
'id' => 'altitude',
'name' => 'Altitude',
'desc' => 'The geo point altitude',
'type' => PropertyType::NUMBER, // int or float.
],
];
}
There are several ways to create a model instance. The model constructor takes an assoc array, an object (including a model instance) or a json string. All the options below produce the same result.
$data = [ latitude => 70.6646625, longitude => 23.6807195 ];
$json = '{"latitude": 70.6646625, "longitude": 23.6807195}';
a) $geo = new GeoPoint( $data );
b) $geo = GeoPoint:create( $data );
c) $geo = GeoPoint:create( (object) $data );
d) $geo = GeoPoint:create( $json );
e) $geo = GeoPoint:create()->patch( $data );
f) $geo = GeoPoint:create()->replace( $data );
g) $geo = GeoPoint:load( 'geopoint.json' );
Or you just create an empty model and add the property values later on.
$geo = new GeoPoint();
$geo->latitude = 70.6646625;
$geo->longitude = 23.6807195;
Just like the ArrayObject parent class, you can also set (and get) model
properties like an array.
$geo = new GeoPoint();
$geo['latitude'] = 70.6646625;
$geo['longitude'] = 23.6807195;
Since each model knows its property definitions and constraints, validating a model is a breeze.
$data = [ latitude => 70.6646625, longitude => 23.6807195 ];
// Returns the model instance on success or null on failure.
$geo = GeoPoint:create( $data )->validate(); // Returns the model instance.
$geo = GeoPoint:create()->validate(); // Returns null.
$geo = GeoPoint:create( [ latitude => 70.6646625 ] )->validate(); // Returns null
Alternatively, you can let the validation throw a ModelException on failure.
$data = [ latitude => 70.6646625, longitude => 23.6807195 ];
// Returns the model instance on success or throws a ModelException on failure.
$geo = GeoPoint:create( $data )->validate( true ); // Returns the model instance.
$geo = GeoPoint:create()->validate( true ); // Throws ModelExeption.
$geo = GeoPoint:create( [ latitude => 70.6646625 ] )->validate( true ); // Throws ModelExeption.
Models are not validated on creation, only when Model::validate() is called.
You can access the model data as an object or array
$geo = GeoPoint:create( [ latitude => 70.6646625, longitude => 23.6807195 ] );
$latitude = $geo->latitude;
$longitude = $geo['longitude'];
or get the model data as an assoc array.
$geo = GeoPoint:create( [ latitude => 70.6646625, longitude => 23.6807195 ] );
$data = $geo->data();
You can easily convert a model to JSON.
$geo = GeoPoint:create( [ latitude => 70.6646625, longitude => 23.6807195 ] );
a) $json = json_encode( $geo );
b) $json = (string) $geo;
Models can contain other models. You just add model with a class name to an
object or array property.
<?php
use Peroks\Model\Model;
use Peroks\Model\PropertyType;
/**
* The Travel model.
*
* @property GeoPoint $from Where the travel starts.
* @property GeoPoint $to Where the travel ends.
*/
class Travel extends Model {
/**
* @var array An array of model properties.
*/
protected static array $properties = [
'from' => [
'id' => 'from',
'name' => 'From geo point',
'type' => PropertyType::OBJECT,
'model' => GeoPoint::class,
'default' => [ latitude => 70.6646625, longitude => 23.6807195 ],
'require' => true,
],
'to' => [
'id' => 'to',
'name' => 'To geo point',
'type' => PropertyType::OBJECT,
'model' => GeoPoint::class,
'default' => [ latitude => 59.8521293, longitude => 10.6590668 ],
'require' => true,
],
];
}
If you add default values for sub-models, they are also created when the main model is created. On validation, sub-models are validated recursively too.
// Validates the travel model and all sub-models.
$travel = Tarvel::create()->validate( true ); // Returns a valid Travel model.
$from = $travel->from; // Returns a GeoPont model, already validated.
Nested models are especially useful for importing complex data structures from external sources. With models, decoding, converting and validating external data is a one-liner.
// Decode, convert and validate external data structures.
$json = $client->import(); // Json encoded string from an api call.
$travel = Tarvel::create( $json )->validate( true );
abstract class PropertyItem {
const ID = 'id'; // string, The property id (required).
const NAME = 'name'; // string, The property name (required).
const DESC = 'desc'; // string, The property description (default: null).
const TYPE = 'type'; // string, The property type (default: PropertyType::MIXED).
const MODEL = 'model'; // string, The class name of a model (default: null).
const OBJECT = 'object'; // string, The class or interface name to validate an object against (default: null).
const FOREIGN = 'foreign'; // string, The property contains an id of the (foreign) model class name (default: null).
const DEFAULT = 'default'; // mixed, The property default value (default: null).
const REQUIRED = 'required'; // bool, Whether the property is required or not (default: false).
const READABLE = 'readable'; // bool, Whether the property is readable or not (default: true).
const WRITABLE = 'writable'; // bool, Whether the property is writable or not (default: true).
const MUTABLE = 'mutable'; // bool, Whether the property is mutable (changeable) or not (default: true).
const UNIQUE = 'unique'; // bool, Whether the property value is unique or not (default: false).
const INDEX = 'index'; // bool, Whether the property is a db index or not (default: false).
const PATTERN = 'pattern'; // string, A regex pattern to validate a string value against (default: null).
const ENUMERATION = 'enumeration'; // array, An enumeration of all valid property values (default: null).
const MIN = 'min'; // int|float, The minimum numeric value or string/array length (default: null).
const MAX = 'max'; // int|float, The maximum numeric value or string/array length (default: null).
const VALUE = 'value'; // mixed, The property value (default: null).
const PROPERTIES = 'properties'; // array, An array of model property definitions (default: null).
}
Currently, the foreign, unique and index property items are not in use.
There is no validation based on these items. They are intended for creating
database tables in future versions. value and properties are ony used for
exporting model data with Model::data( ModelData::PROPERTIES ).
abstract class PropertyType {
const MIXED = ''; // Any type, no validation.
const BOOL = 'boolean';
const NUMBER = 'number'; // Integer or float.
const INTEGER = 'integer';
const FLOAT = 'double';
const STRING = 'string';
const UUID = 'uuid'; // A uuid string.
const URL = 'url'; // A url.
const EMAIL = 'email'; // An email address.
const DATETIME = 'datetime'; // An ISO 8601 datetime string.
const DATE = 'date'; // A date string (Y-m-d).
const TIME = 'time'; // A time string (H:i or H:i:s).
const ARRAY = 'array';
const OBJECT = 'object';
const FUNCTION = 'function'; // A callable function.
}
You need composer to download and install this package.
Just run composer require peroks/model in your project.