pub fn dtls_client_server_request_common<KTY: KeyType, FC, FS>(

    client_key: impl KeyDef<KeyType = KTY> + 'static,

    server_key: impl KeyDef<KeyType = KTY> + 'static + Send,

    client_ctx_setup: FC,

    server_ctx_setup: FS,

) where

    FC: FnOnce(PkiRpkContextBuilder<'static, KTY, NonCertVerifying>) -> PkiRpkContext<'static, KTY> + 'static,

    FS: FnOnce(PkiRpkContextBuilder<'static, KTY, NonCertVerifying>) -> PkiRpkContext<'static, KTY> + Send + 'static,

    ServerPkiRpkCryptoContext<'static>: From<PkiRpkContext<'static, KTY>>,

    ClientCryptoContext<'static>: From<PkiRpkContext<'static, KTY>>,

{

    let server_address = common::get_unused_server_addr();

    let client_crypto_ctx = client_ctx_setup(PkiRpkContextBuilder::<'static, KTY, NonCertVerifying>::new(client_key));

    let server_handle = common::spawn_test_server(move |mut context: CoapContext| {

        let server_crypto_ctx =

            server_ctx_setup(PkiRpkContextBuilder::<'static, KTY, NonCertVerifying>::new(server_key));

        context.set_pki_rpk_context(server_crypto_ctx).unwrap();

        context.add_endpoint_dtls(server_address).unwrap();

        #[cfg(feature = "dtls-pki")]

        context.set_pki_root_ca_paths(Some("./resources/test-keys/ca/ca.crt.pem"), None::<PathBuf>);

        context

    });

    let mut context = CoapContext::new().unwrap();

    #[cfg(feature = "dtls-pki")]

    context.set_pki_root_ca_paths(Some("./resources/test-keys/ca/ca.crt.pem"), None::<PathBuf>);

    let session = CoapClientSession::connect_dtls(&mut context, server_address, client_crypto_ctx).unwrap();

    let request = common::gen_test_request();

    let req_handle = session.send_request(request).unwrap();

        assert!(context.do_io(Some(Duration::from_secs(10))).expect("error during IO") <= Duration::from_secs(10));

        for response in session.poll_handle(&req_handle) {

            assert_eq!(response.code(), CoapMessageCode::Response(CoapResponseCode::Content));

            assert_eq!(response.data().unwrap().as_ref(), "Hello World!".as_bytes());

            server_handle.join().expect("Test server crashed with failure.");

            return;

        }

    }

}