Yii2 CDN Integration

Updated on October 4, 2018

Yii is an open source PHP framework used for developing web 2.0 applications. It allows you to quickly build applications by following 3 steps:

You create the database
Yii generates the base PHP code
You customize the code

The framework also comes with a wide range of features including MVC, design pattern, layered caching scheme, role based access control, testing, etc. In this integration article, we cover the steps required to complete a Yii2 CDN integration.

How to Complete a Yii2 CDN integration

Using Yii in combination with KeyCDN is quite simple. Follow the steps below to complete a Yii2 CDN integration:

Install the required extension through Composer by running php composer.phar require --prefer-dist blacksmoke26/yii2cdn "*" or add "blacksmoke26/yii2cdn": "*" to the require section of your composer.json file.
Under your root folder, create a directory named cdn.
If you are delivering a style.css file for instance, create another folder name style and place your CSS assets within that folder. The path for this should then be /cdn/style.

Open your web.php (@app/config/web.php) file and add property named cdn under the "components" section with the following code:

// ...
'components' => [
    // ...
    'cdn' => [
        'class' => '\yii2cdn\Cdn',
        'baseUrl' => '/cdn',
        'basePath' => dirname(dirname(__DIR__)) . '/cdn',
        'components' => [
            'style' => [
                'css' => [
                    [
                        'css/style.css', // offline
                        '@cdn' => 'https://cdn.yourwebsite.com/css/style.css', // online version
                    ]
                ]
            ]
        ],
    ],
  // ...
],
// ...

In a view file, paste the following:

//...
Yii::$app->cdn->get('style')->register();
//...

Check your HTML source to ensure that the asset URL has be rewritten to use the CDN URL instead of the origin.

Using a Yii extension to purge your KeyCDN Zone

Apart from integrating a CDN into your Yii-based application, you can also use the Yii KeyCDN extension to purge your KeyCDN Zone. To install the extension, you can use the following composer command:

composer require Sammaye/yii2-keycdn "*@dev"

To use the extension it must be defined within the same @app/config/web.php file as mentioned above, under components. For example:

'keycdn' => [
    'class' => 'example\keycdn\KeyCdn',
    'apiKey' => 'your_api_key'
]

Usage examples

Now that the extension is defined, it can be used within your project. A couple of usage examples include:

List Zones GET

var_dump(Yii::$app->keycdn->get('zones.json'));

Purge Zone by URL DELETE

var_dump(Yii::$app->keycdn->delete(
    'zones/purgeurl/{zone_id}.json',
    [
        'urls' =>
        [
            'example-hexid.kxcdn.com/img/lorem.jpg'
        ]
    ]
));

Responses

Responses are returned as PHP's generic empty class stdClass. The following is an expected response when using Purge Zone URL.

object(stdClass)[194]
public 'status' => string 'success' (length=7)
public 'description' => string 'Cache has been cleared for URL(s).' (length=34)

If the response cannot be decoded from JSON or there is a status error, then the extension will throw a yii\base\Exception.

Benefits of using a Yii CDN setup

Use the above method to start delivering your static content via a CDN to help improve performance and reduce latency of your Yii app. Although performance enhancements are a major benefit to using a CDN, there also exists many additional advantages to users who accelerate their Yii framework application with KeyCDN, such as:

Access to our global network of POPs
HTTP/2 supported edge servers
Free Let's Encrypt SSL integration
Hotlink protection with Zone Referrers

For a full list of features that KeyCDN offers, check out our features page.