SSR middleware for react-relay-network-modern (for Relay Modern)
For a full examples, see:
- https://github.com/damassi/react-relay-network-modern-ssr-example
- https://github.com/damassi/react-relay-network-modern-ssr-todomvc
import express from 'express';
import ReactDOMServer from 'react-dom/server';
import { RelayNetworkLayer } from 'react-relay-network-modern';
import RelayServerSSR from 'react-relay-network-modern-ssr/lib/server';
import serialize from 'serialize-javascript';
import { Environment, Network, RecordSource, Store } from 'relay-runtime';
import schema from './schema';
const app = express();
app.get('/*', async (req, res, next) => {
const relayServerSSR = new RelayServerSSR();
const network = new RelayNetworkLayer([
// There are three possible ways relayServerSSR.getMiddleware() can be used;
// choose the one that best matches your context:
// By default, if called without arguments it will use `fetch` under the hood
// to request data. (See https://github.com/relay-tools/react-relay-network-modern
// for more info)
relayServerSSR.getMiddleware(),
// OR, you can directly pass in a GraphQL schema, which will use `graphql`
// from `graphql-js` to request data
relayServerSSR.getMiddleware({
schema,
contextValue: {},
}),
// OR, if you need to prepare context in async mode, `getMiddleware` will also
// accept a function:
relayServerSSR.getMiddleware(async () => ({
schema,
contextValue: await prepareGraphQLContext(req),
})),
]);
const source = new RecordSource();
const store = new Store(source);
const relayEnvironment = new Environment({ network, store });
// Once the RelayEnvironment is instantiated, two App renders need to be made in
// order to prepare data for hydration:
// First, kick off Relay requests with an initial render
ReactDOMServer.renderToString(<App relayEnvironment={relayEnvironment} />);
// Second, await while all data were recieved from graphql server
const relayData = await relayServerSSR.getCache();
// Third, render the app a second time now that the Relay store has been primed
// and send HTML and bootstrap data to the client for rehydration.
const appHtml = ReactDOMServer.renderToString(
<App
relayEnvironment={new Environment({
network: Network.create(() => relayData[0][1]),
store,
})}
/>
);
try {
res.status(200).send(`
<html>
<body>
<div id="react-root">${appHtml}</div>
<script>
window.__RELAY_BOOTSTRAP_DATA__ = ${serialize(relayData)};
</script>
<script src="/assets/bundle.js"></script>
</body>
</html>
`);
} catch (error) {
console.log('(server.js) Error: ', error);
next(error);
}
}
app.listen(3000);
// simple example, how to asynchronously prepare data for GraphQL context
async function prepareGraphQLContext(req) {
const { userToken } = req.cookies;
const user = userToken ? (await somehowLoadUser(userToken)) : undefined;
return {
user,
req,
}
}import { RelayNetworkLayer } from 'react-relay-network-modern';
import RelayClientSSR from 'react-relay-network-modern-ssr/lib/client';
const relayClientSSR = new RelayClientSSR(window.__RELAY_BOOTSTRAP_DATA__);
const network = new RelayNetworkLayer([
relayClientSSR.getMiddleware({
lookup: true // Will preserve cache rather than purge after mount.
}),
]);
...
ReactDOM.render(
<QueryRenderer
dataFrom="STORE_THEN_NETWORK" // Required for Relay 1.5
environment={environment}
...
/>,
document.getElementById('react-root')
);I actively welcome pull requests with code and doc fixes.