Use cache for forms rendering to

[MAILPOET-2639]

lib/API/JSON/v1/Forms.php

@@ -5,6 +5,7 @@ namespace MailPoet\API\JSON\v1;
 use MailPoet\API\JSON\Endpoint as APIEndpoint;
 use MailPoet\API\JSON\Error as APIError;
 use MailPoet\Config\AccessControl;
+use MailPoet\Form\DisplayFormInWPContent;
 use MailPoet\Form\Renderer as FormRenderer;
 use MailPoet\Form\Util;
 use MailPoet\Listing;
@@ -174,6 +175,8 @@ class Forms extends APIEndpoint {
       }
     }
 
+    WPFunctions::get()->deleteTransient(DisplayFormInWPContent::NO_FORM_TRANSIENT_KEY);
+
     // check if the user gets to pick his own lists
     // or if it's selected by the admin
     $hasSegmentSelection = false;

lib/Form/DisplayFormInWPContent.php

@@ -7,31 +7,40 @@ use MailPoet\WP\Functions as WPFunctions;
 
 class DisplayFormInWPContent {
 
+  const NO_FORM_TRANSIENT_KEY = 'no_forms_displayed_bellow_content';
+
   /** @var WPFunctions */
   private $wp;
 
   /** @var FormsRepository */
   private $formsRepository;
 
+  /** @var bool */
+  private $appendedForm = false;
+
   public function __construct(WPFunctions $wp, FormsRepository $formsRepository) {
     $this->wp = $wp;
     $this->formsRepository = $formsRepository;
   }
 
-  // TODO remove transient in the api on form save
-
   public function display(string $content): string {
+    $this->appendedForm = false;
     $result = $content;
     if (!$this->wp->isSingle()) return $result;
+    if ($this->wp->getTransient(DisplayFormInWPContent::NO_FORM_TRANSIENT_KEY)) return $result;
     $forms = $this->formsRepository->findAll();
     foreach ($forms as $form) {
       $result .= $this->getContentBellow($form);
     }
+    if (!$this->appendedForm) {
+      $this->wp->setTransient(DisplayFormInWPContent::NO_FORM_TRANSIENT_KEY, true);
+    }
     return $result;
   }
 
   private function getContentBellow(FormEntity $form): string {
     if (!$this->shouldDisplayFormBellowContent($form)) return '';
+    $this->appendedForm = true;
     return Renderer::render([
       'body' => $form->getBody(),
       'styles' => $form->getStyles(),

lib/WP/Functions.php

@@ -392,7 +392,7 @@ class Functions {
     return self_admin_url($path, $scheme);
   }
 
-  public function setTransient($transient, $value, $expiration) {
+  public function setTransient($transient, $value, $expiration = 0) {
     return set_transient($transient, $value, $expiration);
   }
 

tests/unit/Form/DisplayFormInWPContentTest.php

@@ -137,6 +137,9 @@ class DisplayFormInWPContentTest extends \MailPoetUnitTest {
   public function testAppendsRenderedFormAfterPageContent() {
     $this->wp->expects($this->once())->method('isSingle')->willReturn(true);
     $this->wp->expects($this->any())->method('isPage')->willReturn(true);
+    $this->wp
+      ->expects($this->never())
+      ->method('setTransient');
     $form = new FormEntity('My Form');
     $form->setSettings([
       'segments' => ['3'],
@@ -157,11 +160,29 @@ class DisplayFormInWPContentTest extends \MailPoetUnitTest {
   }
 
   public function testSetsTransientToImprovePerformance() {
+    $this->wp->expects($this->once())->method('isSingle')->willReturn(true);
+    $this->wp->expects($this->any())->method('isPage')->willReturn(false);
+    $this->wp
+      ->expects($this->once())
+      ->method('setTransient');
+    $form1 = new FormEntity('My Form');
+    $form2 = new FormEntity('My Form');
 
+    $this->repository->expects($this->once())->method('findAll')->willReturn([$form1, $form2]);
+
+    $this->hook->display('content');
   }
 
   public function testDoesNotQueryDatabaseIfTransientIsSet() {
+    $this->wp->expects($this->any())->method('isSingle')->willReturn(true);
+    $this->wp->expects($this->any())->method('isPage')->willReturn(false);
+    $this->wp
+      ->expects($this->once())
+      ->method('getTransient')
+      ->willReturn('true');
+    $this->repository->expects($this->never())->method('findAll');
 
+    $this->hook->display('content');
   }
 
 }