If you aren't already familiar, Next.js is a framework for building web applications using React and Node.js.

Why did the Next.js developer stop working on his code? Because it was too "next-tremely" hard!

My goal with this article is to make it "next-tremely" easy for you!

From dynamic routing, code splitting, server-side rendering, static optimization, and more, we will explore the capabilities of Next.js and how to use them to build high-performance web applications.

Whether you are a beginner or an experienced developer, this post will provide you with valuable insights on how to take full advantage of Next.js to build production-ready web applications with ease!

The features we are talking about today include:

• Dynamic routing

Dynamic routing allows for creating URLs that change based on the information displayed on the page.

• Code splitting

Code splitting is a technique that allows for loading only the necessary code for a specific page, improving the performance of the application.

• Server side rendering

Server side rendering involves rendering the initial state of a web page on the server before sending it to the client, saving load time

• Other built-in optimizations

Dynamic Routing

In complex applications, using predefined paths for routes may not be sufficient. Next.js allows developers to use dynamic routes by adding brackets to a page, known as [param]. This allows for creating flexible URLs also known as URL slugs, pretty URLs, and other similar terms.

In this way, Next.js allows for dynamic, parameterized routes to be easily handled without the need for additional configuration.

Consider the following page pages/post/[pid].js:

import { useRouter } from 'next/router'

const Post = () => {
  const router = useRouter()
  const { pid } = router.query

  return <p>Post: {pid}</p>
}

export default Post

Any route like /post/1, /post/abc, etc. will be matched by pages/post/[pid].js. The matched path parameter will be sent as a query.

Server-side rendering

Server-side rendering (SSR) improves the initial load time of a web page by generating the initial state of the page on the server, and sending it as a fully rendered HTML document to the browser. This makes the page more SEO friendly, and allows for faster rendering of the page as the browser does not have to spend time executing JavaScript to render the page.

This is opposed to client-side rendering, where the browser loads and renders the JavaScript, which can take longer and make it less user friendly.

Implementation

In Next.js, server-side rendering is implemented by using a function called getServerSideProps. This function let you fetch data from an API or a database and then pass it as props to your component before the component is rendered on the server.

Here's an example of how you might use getServerSideProps:

import ProductPage from '../components/ProductPage';

export default function Product({product}) {
  return <ProductPage product={product} />;
}

export async function getServerSideProps({params}) {
  // fetch data from an API or database
  const product = await fetch(`https://my-api.com/products/${params.id}`).then(res => res.json());

  return { props: { product } };
}

In this example, the getServerSideProps function is used to fetch data for a specific product based on the {params.id} passed in the URL. The data is then passed as a prop to the Product component.

Once the user navigates to a specific product page, Next.js will execute the getServerSideProps function on the server, fetch the data and render the Product component along with the fetched data before sending it to the browser.

By using server-side rendering, Next.js allows developers to build fast and efficient web applications that are easy for search engines to crawl and index.

Automatic code splitting

This next one isn't so much a tip or trick-- but a showcase of some of the cool stuff that's done for you behind the scenes.

Code splitting is a way of breaking down large JavaScript files into smaller chunks. This way, when a user visits a page, the browser doesn't have to download all the code at once, just the code needed for that specific page. This makes the page load faster and improves the overall performance of the application.

In Next.js, this is done automatically by using a feature called dynamic imports. This allows developers to split the code into smaller chunks that are only loaded when they are needed.

Next.js also splits the code by route, it generates a separate JavaScript file for each page, and it will only download the JavaScript code that's needed for the current page the user is visiting.

Client side navigation

next/link

next/link is a component provided by Next.js that allows you to create client-side navigation between pages in your application. It works by using the href and as props to specify the target route and the actual URL to be displayed in the browser.

Here is an example of how you might use next/link to create a link to a product page:

import Link from 'next/link'

export default function Home() {
  return (
    <div>
      <Link href="/product/123">
        <a>Product 123</a>
      </Link>
    </div>
  )
}

When the user clicks on the link, Next.js will use the href and to navigate to the correct route and update the URL displayed in the browser.

It's worth noting that when you use next/link to navigate between pages, Next.js uses React hydration to perform the navigation. React hydration is the process of taking a pre-rendered HTML and re-activating the React components on the client.

This way, the browser doesn't have to re-render the entire page, instead, it just needs to hydrate the pre-rendered HTML and attach the JavaScript event handlers. This process is faster and it provides a better user experience by avoiding the sudden flash of loading content.

Meta tags

next/head

Very similar to next/link, next/head is a component provided by Next.js that allows you to easily add meta tags and other head elements to your pages.

With next/head, you can set the title, description, keywords, and other meta tags for your pages, and also add custom head elements such as scripts, stylesheets, and links.

To use next/head, you simply import it and then use it as a component in your page. Here's an example of how you might use next/head to set the title and description for your homepage:

import Head from 'next/head'

export default function Home() {
  return (
    <div>
      <Head>
        <title>My Homepage</title>
        <meta name="description" content="Welcome to my homepage!" />
      </Head>
      <p>Welcome to my homepage!</p>
    </div>
  )
}

Here, the Head component is used to set the title and description meta tags for the homepage.

When the page is rendered, the title and description will be added to the head section of the HTML document.

It's worth noting that you can use next/head inside any component in your pages/ directory, not just the top-level component. This allows you to set specific meta tags and head elements for each page in your application.

Also, since we mentioned it earlier, you can use next/head along with getServerSideProps to set meta tags dynamically based on the request context.

Conclusion

Next.js is a fantastic framework for building web apps. I personally tend to gravitate to it because it offers features like dynamic routing, code splitting, server-side rendering, and static optimization to help you create performant and efficient apps.

Tools like next/link and next/head make it easy to handle client-side navigation and set meta tags for your pages. Whether you're a beginner or an experienced developer, Next.js is a great choice for building web apps. With the right approach, you can create high-quality, production-ready apps in no time.

If you are looking for more resources to learn more about Next.js, check out the official docs

I hope you use these tricks in this post in your next project! Stay tuned for a part 2! Thanks for reading, and HAPPY CODING!!