Router Prefetch Next Js Simplified for Developers

Next Js allows developers to enable automatic prefetching of routes using the `getStaticProps` function, which can improve page load times and user experience.

With Next Js, developers can use the `useEffect` hook to prefetch routes on client-side rendering, which is useful for dynamic routes that require server-side rendering.

Next Js also supports automatic prefetching of routes using the `Link` component, which is a built-in component for client-side navigation.

By leveraging these features, developers can simplify their code and improve performance.

Next.js provides an easy-to-use, file-based routing mechanism. Every file placed inside the pages directory automatically maps to a route in the application.

This means you don't need to use external routing libraries, which can save you time and effort. You can simply define files in the pages folder to create routes.

Routes are created by simply placing files in the pages directory, which makes it easy to organize and manage your application's routes.

Programmatic routing with Next.js is a powerful feature that allows you to control routing with custom logic using the next/link component and router.push.

You can programmatically control routing with custom logic using the next/link component and router.push, which is useful when you need to trigger navigation based on user interaction or some internal logic.

This method helps you create dynamic, user-driven route changes, making it perfect for scenarios where you need to adapt to user behavior.

Next.js provides a powerful method to programmatically prefetch routes using the prefetch method on the router object returned from the useRouter hook, allowing you to prefetch specific routes in advance for a seamless and instant transition.

Programmatically, you can control routing with custom logic using the next/link component and router.push. This approach is useful when you need to trigger navigation based on user interaction or some internal logic.

You can programmatically prefetch routes using the prefetch method on the router object returned from the useRouter hook. This method is particularly useful when you know beforehand that the user is likely to navigate to a particular page.

By calling router.prefetch() with the full path of a route, you can prefetch that specific route. Prefetching a route in advance ensures a seamless and instant transition without any additional requests.

During development, Next.js 13 makes prefetching routes a breeze. It happens automatically when you hover over a Link component in the user interface, fetching and caching the content of the next page based on your interactions.

This seamless experience gives you a glimpse of how the final performance will look and feel.

Prefetching is a technique used to speed up the loading of web pages by preloading some content in the background before it's actually needed.

Next.js prefetches only links that appear in the viewport and uses the Intersection Observer API to detect them. It also disables prefetching when the network connection is slow or when users have Save-Data turned on.

The prefetch keyword for the rel attribute of the link element is a hint to browsers that the user is likely to need the target resource for future navigations, and therefore the browser can likely improve the user experience by preemptively fetching and caching the resource.

To implement prefetching in your routing code, use the prefetch method from useRouter, which is done inside the useEffect hook. If the prefetch property on a custom routing component is set to true, the route specified in the href property gets prefetched when that component is rendered.

Next.js only fetches the JavaScript; it doesn't execute it. That way, it's not downloading any additional content that the prefetched page might request until you visit the link.

In production, routes are prefetched as they become visible in the viewport. This can occur during the initial page load or when the user scrolls through the website. As soon as a Link comes into view, Next.js proactively fetches and caches the route content, ensuring that when the user clicks on a link to navigate, the page transition is instantaneous.

The Network tab shows that the prefetched content is downloaded and cached before the user requests it, eliminating any noticeable delay.

Integration is a key aspect of router prefetching in Next.js, and there are several approaches to consider.

You can integrate prefetching at the router level, which is a common approach for Server Rendering. This involves declaring the data needed for each route ahead of time.

This approach has been the dominating method for SSR'd apps for a long time, but it can also work well on the client-side.

You can choose to either block rendering of a route until all data is present, or start a prefetch but not await the result. This allows you to start rendering the route as soon as possible.

You can also mix these two approaches and await some critical data, but start rendering before all secondary data has finished loading. In this example, we'll configure an /article route to not render until the article data has finished loading.

Integration with other routers is also possible, such as with React Router.