Add custom fields to the response

[MAILPOET-2653]

lib/Entities/SubscriberCustomFieldEntity.php

@@ -0,0 +1,67 @@
+<?php
+
+namespace MailPoet\Entities;
+
+use MailPoet\Doctrine\EntityTraits\AutoincrementedIdTrait;
+use MailPoet\Doctrine\EntityTraits\CreatedAtTrait;
+use MailPoet\Doctrine\EntityTraits\SafeToOneAssociationLoadTrait;
+use MailPoet\Doctrine\EntityTraits\UpdatedAtTrait;
+use MailPoetVendor\Doctrine\ORM\Mapping as ORM;
+
+/**
+ * @ORM\Entity()
+ * @ORM\Table(name="subscriber_custom_field")
+ */
+class SubscriberCustomFieldEntity {
+  use AutoincrementedIdTrait;
+  use CreatedAtTrait;
+  use UpdatedAtTrait;
+  use SafeToOneAssociationLoadTrait;
+
+  /**
+   * @ORM\ManyToOne(targetEntity="MailPoet\Entities\SubscriberEntity")
+   * @var SubscriberEntity|null
+   */
+  private $subscriber;
+
+  /**
+   * @ORM\ManyToOne(targetEntity="MailPoet\Entities\CustomFieldEntity")
+   * @var CustomFieldEntity|null
+   */
+  private $customField;
+
+  /**
+   * @ORM\Column(type="string")
+   * @var string
+   */
+  private $value;
+
+  public function __construct(
+    SubscriberEntity $subscriber,
+    CustomFieldEntity $customField,
+    string $value
+  ) {
+    $this->subscriber = $subscriber;
+    $this->customField = $customField;
+    $this->value = $value;
+  }
+
+  /**
+   * @return SubscriberEntity|null
+   */
+  public function getSubscriber() {
+    $this->safelyLoadToOneAssociation('subscriber');
+    return $this->subscriber;
+  }
+
+  public function getValue(): string {
+    return $this->value;
+  }
+
+  /**
+   * @return CustomFieldEntity|null
+   */
+  public function getCustomField() {
+    return $this->customField;
+  }
+}