Code exerpts from universal-react-router4 – server/index.js

index.js

const routes = [
    '/',
    '/g/:gistId'
];

app.get('*', (req, res) => {
    const match = routes.reduce((acc, route) => matchPath(req.url, route, { exact: true }) || acc, null);
    if (!match) {
        res.status(404).send(render(<NoMatch />));
        return;
    }
    fetch('https://api.github.com/gists')
        .then(r => r.json())
        .then(gists => 
            res.status(200).send(render(
                (
                    <StaticRouter context={{}} location={req.url}>
                        <App gists={gists} />
                    </StaticRouter>
                ), gists
            ))
        ).catch(err => res.status(500).send(render(<Error />));
});

app.listen(3000, () => console.log('Demo app listening on port 3000'));