def test_resolve_service_from_env(self, monkeypatch, service):
        monkeypatch.setenv(service.upper() + "_SERVICE_HOST", "host")
        monkeypatch.setenv(service.upper() + "_SERVICE_PORT", "1234")
        config = Configuration([])

        host, port = config.resolve_service(service)
        assert host == "host"
        assert port == 1234
    def test_resolve_service_from_dns(self, dns_resolver):
        dns_resolver.side_effect = None
        dns_resolver.return_value = dns.rdataset.from_text(
            'IN', 'SRV', 3600,
            '10 100 7794 kafka-pipeline.default.svc.cluster.local.')

        config = Configuration([])

        target, port = config.resolve_service('service', 'port')
        assert target == 'kafka-pipeline.default.svc.cluster.local'
        assert port == 7794