client = $client; $this->listId = $listId; } public function subscribe($email): void { $this->client->post('lists/' . $this->listId . '/members', [ 'email_address' => $email, 'status' => 'subscribed', ]); if ($error = $this->client->getLastError()) { throw new RuntimeException($error); } } public function unsubscribe($email): void { $hash = $this->client->subscriberHash($email); $this->client->delete('lists/' . $this->listId . '/members/' . $hash); if ($error = $this->client->getLastError()) { throw new RuntimeException($error); } } }