add vary data applicator mechanism with customer group example

Author: David Verholen

Model/VaryData/Applicator/CustomerGroupApplicator.php

@@ -0,0 +1,36 @@
+<?php
+declare(strict_types=1);
+
+namespace Firegento\CacheWarmup\Model\VaryData\Applicator;
+
+use Magento\Customer\Model\CustomerFactory;
+use Magento\Customer\Model\Session;
+
+class CustomerGroupApplicator implements VaryDataApplicatorInterface
+{
+    private const VARY_DATA_KEY = 'customer_group';
+
+    /**
+     * @var Session
+     */
+    private $customerSession;
+    /**
+     * @var CustomerFactory
+     */
+    private $customerFactory;
+
+    public function __construct(Session $customerSession, CustomerFactory $customerFactory)
+    {
+        $this->customerSession = $customerSession;
+        $this->customerFactory = $customerFactory;
+    }
+
+    public function apply(array $varyData): void
+    {
+        $this->customerSession->clearStorage();
+        $customerGroupId = $varyData[self::VARY_DATA_KEY];
+        $customer = $this->customerFactory->create()->setGroupId($customerGroupId);
+        $this->customerSession->setCustomerGroupId($customerGroupId);
+        $this->customerSession->setCustomer($customer);
+    }
+}

Model/VaryData/Applicator/VaryDataApplicatorInterface.php

@@ -0,0 +1,9 @@
+<?php
+declare(strict_types=1);
+
+namespace Firegento\CacheWarmup\Model\VaryData\Applicator;
+
+interface VaryDataApplicatorInterface
+{
+    public function apply(array $varyData): void;
+}

Model/VaryData/Applicator/VaryDataApplicatorList.php

@@ -0,0 +1,28 @@
+<?php
+declare(strict_types=1);
+
+namespace Firegento\CacheWarmup\Model\VaryData\Applicator;
+
+class VaryDataApplicatorList
+{
+    /**
+     * @var VaryDataApplicatorInterface[]
+     */
+    private $varyDataApplicators;
+
+    /**
+     * VaryDataApplicatorList constructor.
+     * @param VaryDataApplicatorInterface[] $varyDataApplicators
+     */
+    public function __construct(array $varyDataApplicators = [])
+    {
+        $this->varyDataApplicators = $varyDataApplicators;
+    }
+
+    public function applyAll(array $varyData): void
+    {
+        foreach ($this->varyDataApplicators as $varyDataApplicator) {
+            $varyDataApplicator->apply($varyData);
+        }
+    }
+}

etc/frontend/di.xml

@@ -3,4 +3,11 @@
     <type name="Magento\Framework\App\PageCache\Identifier">
         <plugin name="saveVaryData" type="\Firegento\CacheWarmup\Plugin\CacheIdentifier\SaveVaryData"/>
     </type>
+    <type name="Firegento\CacheWarmup\Model\VaryData\Applicator\VaryDataApplicatorList">
+        <arguments>
+            <argument name="varyDataApplicators" xsi:type="array">
+                <item name="customer_group" xsi:type="object">Firegento\CacheWarmup\Model\VaryData\Applicator\CustomerGroupApplicator</item>
+            </argument>
+        </arguments>
+    </type>
 </config>