src/OwpPostmark.inc.php
public function send()
    {
        $client = new GuzzleHttp\Client();

        $response    = $client->request(
            'POST', "https://api.postmarkapp.com/email",
            [
                'http_errors' => false,
                'verify' => false,
                'connect_timeout' => 5,
                'timeout' => 30,
                'headers' => [
                    'Accept' => 'application/json',
                    'Content-Type' => 'application/json',
                    'X-Postmark-Server-Token' => $this->api_key
                ],
                'body' => json_encode($this->data)
            ]
        );

        if($response->getStatusCode() != 200) {
            return false;
        }

        if($response->getBody()) {
            return true;
        } else {
            return false;
        }
    }
public function send()
    {
        $client = new GuzzleHttp\Client();

        $response    = $client->request(
            'POST', "https://api.postmarkapp.com/email",
            [
                'http_errors' => false,
                'verify' => false,
                'connect_timeout' => 5,
                'timeout' => 30,
                'headers' => [
                    'Accept' => 'application/json',
                    'Content-Type' => 'application/json',
                    'X-Postmark-Server-Token' => $this->api_key
                ],
                'body' => json_encode($this->data)
            ]
        );

        if($response->getStatusCode() != 200) {
            return false;
        }

        if($response->getBody()) {
            return true;
        } else {
            return false;
        }
    }
Send method

@method void send() Send method
@access public
@return bool