Yii - Using Cookies

Cookies allow data to be persisted across requests. In PHP, you may access them through the $_COOKIE variable. Yii represents cookie as an object of the yiiwebCookie class. In this chapter, we describe several methods for reading cookies.

Step 1 − Create an actionReadCookies method in the SiteController.

pubpc function actionReadCookies() { 
   // get cookies from the "request" component 
   $cookies = Yii::$app->request->cookies; 
   // get the "language" cookie value 
   // if the cookie does not exist, return "ru" as the default value 
   $language = $cookies->getValue( language ,  ru ); 
   // an alternative way of getting the "language" cookie value 
   if (($cookie = $cookies->get( language )) !== null) { 
      $language = $cookie->value; 
   } 
   // you may also use $cookies pke an array 
   if (isset($cookies[ language ])) { 
      $language = $cookies[ language ]->value; 
   } 
   // check if there is a "language" cookie 
   if ($cookies->has( language )) echo "Current language: $language"; 
}

Step 2 − To see sending cookies in action, create a method called actionSendCookies in the SiteController.

pubpc function actionSendCookies() { 
   // get cookies from the "response" component 
   $cookies = Yii::$app->response->cookies; 
   // add a new cookie to the response to be sent 
   $cookies->add(new yiiwebCookie([ 
       name  =>  language , 
       value  =>  ru-RU , 
   ])); 
   $cookies->add(new yiiwebCookie([
       name  =>  username , 
       value  =>  John , 
   ])); 
   $cookies->add(new yiiwebCookie([ 
       name  =>  country , 
       value  =>  USA , 
   ])); 
} 

Step 3 − Now, if you go to http://localhost:8080/index.php?r=site/send-cookies, you will notice that cookies are saved inside the browser.

In Yii, by default, cookie vapdation is enabled. It protects the cookies from being modified on the cpent side. The hash string from the config/web.php file signs each cookie.

<?php 
   $params = require(__DIR__ .  /params.php ); 
   $config = [ 
       id  =>  basic , 
       basePath  => dirname(__DIR__), 
       bootstrap  => [ log ], 
       components  => [ 
          request  => [ 
            // !!! insert a secret key in the following (if it is empty) - this is 
            //required by cookie vapdation 
             cookieVapdationKey  =>  ymoaYrebZHa8gURuopoHGlK8fLXCKjO , 
         ], 
          cache  => [ 
             class  =>  yiicachingFileCache , 
         ], 
          user  => [ 
             identityClass  =>  appmodelsUser , 
             enableAutoLogin  => true, 
         ], 
          errorHandler  => [ 
             errorAction  =>  site/error , 
         ], 
          mailer  => [ 
             class  =>  yiiswiftmailerMailer , 
            // send all mails to a file by default. You have to set 
            //  useFileTransport  to false and configure a transport 
            // for the mailer to send real emails. 
             useFileTransport  => true, 
         ], 
          log  => [ 
             traceLevel  => YII_DEBUG ? 3 : 0, 
             targets  => [ 
               [ 
                   class  =>  yiilogFileTarget , 
                      levels  => [ error ,  warning ], 
                ], 
            ], 
         ], 
          urlManager  => [ 
            // showScriptName  => false, 
            // enablePrettyUrl  => true, 
            // enableStrictParsing  => true, 
            // suffix  =>  /  
         ], 
          db  => require(__DIR__ .  /db.php ), 
      ], 
       modules  => [ 
          hello  => [ 
             class  =>  appmoduleshelloHello , 
         ], 
      ], 
       params  => $params,
   ]; 
   if (YII_ENV_DEV) { 
      // configuration adjustments for  dev  environment 
      $config[ bootstrap ][] =  debug ; 
      $config[ modules ][ debug ] = [ 
          class  =>  yiidebugModule , 
      ]; 
      $config[ bootstrap ][] =  gii ; 
      $config[ modules ][ gii ] = [ 
          class  =>  yiigiiModule , 
      ]; 
   } 
   return $config; 
?>

You can disable cookie vapdation by setting the yiiwebRequest::$enableCookieVapdation property to false.