public function getCampaigns()
    {
        $resource = 'campaigns.json';

        $response = $this->sendRequest('GET', $this->getServiceUrl($resource));

        $decodedResponseBody = $this->getDecodedBody($response->getBody());

        $getCampaignsResponse = new GetCampaignsResponse($decodedResponseBody);
        return $getCampaignsResponse->getCampaigns();
    }