public function setDomain(string $domain): self
    {
        $this->url = $this->baseUrl . '/v3/' . $domain . '/messages.mime';

        $this->domain = $domain;

        return $this;
    }
public function setDomain(string $domain): self
    {
        $this->url = $this->baseUrl . '/v3/' . $domain . '/messages.mime';

        $this->domain = $domain;

        return $this;
    }
public function setDomain ( string $ domain ) : self { $ this -> url = $ this -> baseUrl . '/v3/' . $ domain . '/messages.mime' ; $ this -> domain = $ domain ; return $ this ; }
Set the domain being used by the transport.

@param string $domain

@return $this
Set the domain being used by the transport .