yii2 yii 2 php yii 2 yii2 highlights latest features yii2 yii 2 RESTful APIs yii 2 yii2 Adopting Standards and Latest Technologies yii2 yii 2 Solid Foundation Classes yii2 yii 2 Security yii2 yii 2 Database Caching forms yii2 yii 2 Authentication and Authorization Widgets Helpers yii2 yii 2 Internationalization Template Engines Testing Application Templates
Adopting Standards and Latest Technologies
Yii 2.0 adopts PHP namespaces and traits, PSR standards, Composer and Bower. All these make the framework more refreshing and interoperable with other libraries.Solid Foundation Classes
Like in 1.1, Yii 2.0 supports object properties defined via getters and setters, configurations, events and behaviors. The new implementation is more efficient and expressive. For example, you can write the following code to respond to an event:$response = new yii\web\Response;
$response->on('beforeSend', function ($event) {
// respond to the "beforeSend" event here
});
Development Tools
Yii 2.0 comes with several development tools to make the life of developers easier.The Yii debugger allows you to examine the runtime internals of your application. It can also be used to do performance profiling to find out the performance bottlenecks in your application.
Like 1.1, Yii 2.0 also provides Gii, a code generation tool, that can cut down a large portion of your development time. Gii is very extensible, allowing you to customize or create different code generators. Gii provides both Web and console interfaces to fit for different user preferences.
The API documentation of Yii 1.1 has received a lot of positive feedback. Many people expressed the wish to create a similar documentation for their applications. Yii 2.0 realizes this with a documentation generator. The generator supports Markdown syntax which allows you to write documentation in a more succinct and expressive fashion.
Security
Yii 2.0 helps you to write more secure code. It has built-in support to prevent SQL injections, XSS attacks, CSRF attacks, cookie tampering, etc. Security experts Tom Worster and Anthony Ferrara even helped us review and rewrite some of the security-related code.Databases
Working with databases has never been easier. Yii 2.0 supports DB migration, database access objects (DAO), query builder and Active Record. Compared with 1.1, Yii 2.0 improves the performance of Active Record and unifies the syntax for querying data via query builder and Active Record. The following code shows how you can query customer data using either query builder or Active Record. As you can see, both approaches use chained method calls which are similar to SQL syntax.use yii\db\Query;
use app\models\Customer;
$customers = (new Query)->from('customer')
->where(['status' => Customer::STATUS_ACTIVE])
->orderBy('id')
->all();
$customers = Customer::find()
->where(['status' => Customer::STATUS_ACTIVE])
->orderBy('id')
->asArray();
->all();
namespace app\models;
use app\models\Order;
use yii\db\ActiveRecord;
class Customer extends ActiveRecord
{
public static function tableName()
{
return 'customer';
}
// defines a one-to-many relation with Order model
public function getOrders()
{
return $this->hasMany(Order::className(), ['customer_id' => 'id']);
}
}
// returns the customer whose id is 100
$customer = Customer::findOne(100);
// returns the orders for the customer
$orders = $customer->orders;
$customer = Customer::findOne(100);
$customer->address = '123 Anderson St';
$customer->save(); // executes SQL: UPDATE `customer` SET `address`='123 Anderson St' WHERE `id`=100
For applications with big databases and high performance requirement, Yii 2.0 also provides built-in support for database replication and read-write splitting.
RESTful APIs
With a few lines of code, Yii 2.0 lets you to quickly build a set of fully functional RESTful APIs that comply to the latest protocols. The following example shows how you can create a RESTful API serving user data.First, create a controller class
app\controllers\UserController and specify app\models\User as the type of model being served:namespace app\controllers;
use yii\rest\ActiveController;
class UserController extends ActiveController
{
public $modelClass = 'app\models\User';
}
urlManager component in your application configuration to serve user data in pretty URLs:'urlManager' => [
'enablePrettyUrl' => true,
'enableStrictParsing' => true,
'showScriptName' => false,
'rules' => [
['class' => 'yii\rest\UrlRule', 'controller' => 'user'],
],
]
GET /users: list all users page by page;HEAD /users: show the overview information of user listing;POST /users: create a new user;GET /users/123: return the details of the user 123;HEAD /users/123: show the overview information of user 123;PATCH /users/123andPUT /users/123: update the user 123;DELETE /users/123: delete the user 123;OPTIONS /users: show the supported verbs regarding endpoint/users;OPTIONS /users/123: show the supported verbs regarding endpoint/users/123.
curl command like the following,$ curl -i -H "Accept:application/json" "http://localhost/users"
HTTP/1.1 200 OK
Date: Sun, 02 Mar 2014 05:31:43 GMT
Server: Apache/2.2.26 (Unix) DAV/2 PHP/5.4.20 mod_ssl/2.2.26 OpenSSL/0.9.8y
X-Powered-By: PHP/5.4.20
X-Pagination-Total-Count: 1000
X-Pagination-Page-Count: 50
X-Pagination-Current-Page: 1
X-Pagination-Per-Page: 20
Link: <http://localhost/users?page=1>; rel=self,
<http://localhost/users?page=2>; rel=next,
<http://localhost/users?page=50>; rel=last
Transfer-Encoding: chunked
Content-Type: application/json; charset=UTF-8
[
{
"id": 1,
...
},
{
"id": 2,
...
},
...
]
Caching
Like 1.1, Yii 2.0 supports a whole range of caching options, from server side caching, such as fragment caching, query caching to client side HTTP caching. They are supported on a variety of caching drivers, including APC, Memcache, files, databases, etc.Forms
In 1.1, you can quickly create HTML forms that support both client side and server side validation. In Yii 2.0, it is even easier working with forms. The following example shows how you can create a login form.First create a
LoginForm model to represent the data being collected. In this class, you will list the rules
that should be used to validate the user input. The validation rules will later be used to automatically generate
the needed client-side JavaScript validation logic.use yii\base\Model;
class LoginForm extends Model
{
public $username;
public $password;
/**
* @return array the validation rules.
*/
public function rules()
{
return [
// username and password are both required
[['username', 'password'], 'required'],
// password is validated by validatePassword()
['password', 'validatePassword'],
];
}
/**
* Validates the password.
* This method serves as the inline validation for password.
*/
public function validatePassword()
{
$user = User::findByUsername($this->username);
if (!$user || !$user->validatePassword($this->password)) {
$this->addError('password', 'Incorrect username or password.');
}
}
}
use yii\helpers\Html;
use yii\widgets\ActiveForm;
<?php $form = ActiveForm::begin()
<?= $form->field($model, 'username')
<?= $form->field($model, 'password')->passwordInput()
<?= Html::submitButton('Login')
<? ActiveForm::end()
Authentication and Authorization
Like 1.1, Yii 2.0 provides built-in support for user authentication and authorization. It supports features such as login, logout, cookie-based and token-based authentication, access control filter and role-based access control (RBAC).Yii 2.0 also provides the ability of the authentication via external credentials providers. It supports OpenID, OAuth1 and OAuth2 protocols.
Widgets
Yii 2.0 comes with a rich set of user interface elements, called widgets, to help you quickly build interactive user interfaces. It has built-in support for Bootstrap widgets and jQuery UI widgets. It also provides commonly used widgets such as pagers, grid view, list view, detail, all of which make Web application development a truly speedy and enjoyable process. For example, with the following lines of code, you can create a fully functional jQuery UI date picker in Russian:use yii\jui\DatePicker;
echo DatePicker::widget([
'name' => 'date',
'language' => 'ru',
'dateFormat' => 'yyyy-MM-dd',
]);
Helpers
Yii 2.0 provides many useful helper classes to simplify some common tasks. For example, theHtml helper includes a set of methods to create different
HTML tags, and the Url helper lets you more easily creates various URLs, like shown below:use yii\helpers\Html;
use yii\helpers\Url;
// creates a checkbox list of countries
echo Html::checkboxList('country', 'USA', $countries);
// generates a URL like "/index?r=site/index&src=ref1#name"
echo Url::to(['site/index', 'src' => 'ref1', '#' => 'name']);
Internationalization
Yii has strong support for internationalization, as it is being used all over the world. It supports message translation as well as view translation. It also supports locale-based plural forms and data formatting, which complies to the ICU standard. For example,// message translation with date formatting
echo \Yii::t('app', 'Today is {0, date}', time());
// message translation with plural forms
echo \Yii::t('app', 'There {n, plural, =0{are no cats} =1{is one cat} other{are # cats}}!', ['n' => 0]);
