Performing Client Transitions

React-server provides blazing fast server-side render of web pages. This is important for landing experience and for web crawlers, but it's only part of the picture! The great strength of react-server is that the same code runs in the browser. Once you've loaded a page, you could ask the server to render the next page for you, but why bother? Why not just fetch the data for the page and render it yourself?

That's where client transitions come in. Navigation between react-server pages can be done without ever hitting the server. It's easy. Pages don't need to do anything tricky to make this work. It's part of the framework!

The <Link> component

How easy is it?

const {Link} = require("react-server");

const MyPageLink = () => <Link path="/my-page">My page!</Link>

That easy! The <Link> component exported by react-server produces <a> tags with click handlers that automatically turn normal navigation into client transitions. Middle-clicks, command-clicks, etc, all still behave as expected, but a normal left-click to navigate becomes a light-weight transition within the browser.

The navigateTo() function

Want to manage your own <a> tags and click handlers? Want to navigate based on some other action?

const {navigateTo} = require("react-server");


This is what the <Link> tag does for you on click.

The Options

Just transitioning from page to page in the browser is great, but if you know a little bit about the type of navigation ahead of time you can make it even better. Here are some options for improving client transitions. Each of these may be passed either as a prop on a <Link> tag or as a key/value pair in an options object passed as a second argument to the navigateTo function.


<Link path={path} bundleData={true}>...</Link>

navigateTo(path, {bundleData: true});

In order to render the new page in the browser, we first need to fetch the data for the new page. When the server renders a page for us it makes upstream data requests and then transfers the results to the browser in a data bundle. When the browser re-renders the page it makes the same requests, but the data is already pre-loaded so no actual XHRs go out. When we render a new page in the browser we need to make all of the upstream requests that the server would have made for us. This could be a lot of requests. Browsers may not let us make all of the requests in parallel. Some might get delayed.

But the server already knows how to make those requests, and it knows how to bundle the results up for us! So, we can ask the server just for the data bundle for a page. Then, when we make our upstream data requests, we find the results in the bundle and we don't need to fire actual XHRs!


<Link path={path} reuseDom={true}>...</Link>

navigateTo(path, {reuseDom: true});

This is useful for "single-page app" style navigation, where there may be UI that's shared between page (for example a tab-set or a sidebar menu). With ordinary navigation, and by default with client transitions, the DOM is blown away and recreated each time you navigate. With reuseDom portions of the page that are the same as the previous page are re-used. This includes React component state! This is single page app navigation done right.