ACP2E-1361: Customer is not getting product price drop email for subsequent product price changes

Author: bubasuma

app/code/Magento/ProductAlert/Model/Mailing/AlertProcessor.php

@@ -27,6 +27,8 @@
 
 /**
  * Class for mailing Product Alerts
+ *
+ * @SuppressWarnings(PHPMD.CouplingBetweenObjects)
  */
 class AlertProcessor
 {
@@ -139,6 +141,7 @@ public function process(string $alertType, array $customerIds, int $websiteId):
      * @param int $websiteId
      * @return array
      * @throws \Exception
+     * @SuppressWarnings(PHPMD.CyclomaticComplexity)
      */
     private function processAlerts(string $alertType, array $customerIds, int $websiteId): array
     {
@@ -160,6 +163,7 @@ private function processAlerts(string $alertType, array $customerIds, int $websi
         /** @var Website $website */
         $website = $this->storeManager->getWebsite($websiteId);
         $defaultStoreId = $website->getDefaultStore()->getId();
+        $products = [];
 
         /** @var Price|Stock $alert */
         foreach ($collection as $alert) {
@@ -174,7 +178,12 @@ private function processAlerts(string $alertType, array $customerIds, int $websi
                     $customer = $this->customerRepository->getById($alert->getCustomerId());
                 }
 
-                $product = $this->productRepository->getById($alert->getProductId(), false, $defaultStoreId);
+                if (!isset($products[$alert->getProductId()])) {
+                    $product = $this->productRepository->getById($alert->getProductId(), false, $defaultStoreId, true);
+                    $products[$alert->getProductId()] = $product;
+                } else {
+                    $product = $products[$alert->getProductId()];
+                }
 
                 switch ($alertType) {
                     case self::ALERT_TYPE_STOCK:

dev/tests/integration/testsuite/Magento/ProductAlert/Model/Mailing/AlertProcessorTest.php

@@ -7,6 +7,9 @@
 
 namespace Magento\ProductAlert\Model\Mailing;
 
+use Magento\Catalog\Api\ProductRepositoryInterface;
+use Magento\Catalog\Model\ProductFactory;
+use Magento\Catalog\Model\ResourceModel\Product as ProductResourceModel;
 use Magento\Customer\Api\AccountManagementInterface;
 use Magento\Customer\Model\Session;
 use Magento\Framework\App\Area;
@@ -16,18 +19,20 @@
 use Magento\Framework\Phrase\Renderer\Translate as PhraseRendererTranslate;
 use Magento\Framework\Phrase\RendererInterface;
 use Magento\Framework\Translate;
+use Magento\Store\Model\Store;
 use Magento\Store\Model\StoreRepository;
 use Magento\TestFramework\Helper\Bootstrap;
 use Magento\TestFramework\Mail\Template\TransportBuilderMock;
 use Magento\TestFramework\ObjectManager;
 use PHPUnit\Framework\TestCase;
 
 /**
-* Test for Product Alert observer
-*
-* @magentoAppIsolation enabled
-* @magentoAppArea frontend
-*/
+ * Test for Product Alert observer
+ *
+ * @magentoAppIsolation enabled
+ * @magentoAppArea frontend
+ * @SuppressWarnings(PHPMD.CouplingBetweenObjects)
+ */
 class AlertProcessorTest extends TestCase
 {
     /**
@@ -127,6 +132,37 @@ public function testProcessPortuguese()
         $this->assertStringContainsString(substr($expectedText, 0, 50), $messageContent);
     }
 
+    /**
+     * @magentoConfigFixture current_store catalog/productalert/allow_price 1
+     * @magentoDataFixture Magento/ProductAlert/_files/product_alert.php
+     */
+    public function testCustomerShouldGetEmailForEveryProductPriceDrop(): void
+    {
+        $this->processAlerts();
+
+        $this->assertStringContainsString(
+            '$10.00',
+            $this->transportBuilder->getSentMessage()->getBody()->getParts()[0]->getRawContent()
+        );
+
+        // Intentional: update product without using ProductRepository
+        // to prevent changes from being cached on application level
+        $product = $this->objectManager->get(ProductFactory::class)->create();
+        $productRepository = $this->objectManager->get(ProductRepositoryInterface::class);
+        $productResource = $this->objectManager->get(ProductResourceModel::class);
+        $product->setStoreId(Store::DEFAULT_STORE_ID);
+        $productResource->load($product, $productRepository->get('simple')->getId());
+        $product->setPrice(5);
+        $productResource->save($product);
+
+        $this->processAlerts();
+
+        $this->assertStringContainsString(
+            '$5.00',
+            $this->transportBuilder->getSentMessage()->getBody()->getParts()[0]->getRawContent()
+        );
+    }
+
     /**
      * Process price alerts
      */