Ever wondered, What the hell is hydration when it comes to development in meta-frameworks? No more worries now, I am here to explain you

• Defination of Hydration.
• Client Side Rendering (CSR)
• Server Side Rendering(SSR)
• What problem does hydration solves ?
• Drawbacks of hydration.
• Is hydration the optimal solution or just a workaround ?'
• Conclusion

without wasting more time, let's explore Hydration.

Defination of Hydration

Wikpedia says

In web development, hydration or rehydration is a technique in which client-side JavaScript converts a static HTML web page, delivered either through static hosting or server-side rendering, into a dynamic web page by attaching event handlers to the HTML elements.

Technially, The process of populating data to an existing empty object is called hydration. To make the object useful, we should fill the object with relevant domain data, which can be done by filling it with data. You can expect data to come from database, network or certain file systems sometimes configurations.

In terms of web development, hydration is simply the process of enabling the interactivity to the HTML elements that have been generated on the server.

To understand hydration in more detail, we need to understand following concepts :

• Client-side rendering
• Server-side rendering

Client-Side Rendering(CSR)

Client-side rendering (CSR) is a key concept in web development where the application is constructed on the user's browser, rather than pre-rendered on the server. This is how it works:

When you visit a website, your browser sends a request to the server. In response, the server sends back HTML, CSS, and JavaScript files. These files contain all the necessary instructions to build and run the web application directly in your browser.

Once these files are received, your browser gets into action. It interprets and executes the JavaScript code, piecing together the visual elements of the application and making it interactive. This process, often referred to as bundling, involves combining multiple JavaScript files into a single bundle for efficiency.

One of the challenges developers face with CSR is its impact on performance and search engine optimization (SEO). Because search engines rely heavily on HTML content for indexing, they may struggle to understand and rank content that's rendered dynamically via JavaScript. Additionally, since the entire application needs to be downloaded and processed by the browser before it can be displayed, CSR can sometimes lead to slower initial load times.

Despite these challenges, CSR offers benefits such as enhanced interactivity and a more responsive user experience. By understanding its intricacies, developers can leverage CSR effectively while mitigating its drawbacks.

This is how traditional web development use to work, then it comes the new concept of server-side rendering

Server-Side Rendering(SSR)

Server-side rendering (SSR) is a fundamental aspect of web development where the web page is generated on the server and sent to the user's browser as a complete HTML document. Here's a breakdown of how SSR works:

When you request a webpage, the server dynamically creates the HTML, CSS, and JavaScript needed to render the page based on your request. Unlike client-side rendering, where much of the work is done in the browser, SSR pre-builds the page on the server before sending it to your browser.

This means that when you receive the webpage, it's already fully formed and ready to be displayed. There's no need for your browser to wait for JavaScript files to download and execute before rendering the content, leading to faster initial load times and improved SEO performance.

From a developer's perspective, SSR simplifies certain aspects of web development. For example, since the HTML is generated on the server, search engines can easily crawl and index the content, boosting the website's visibility in search results.

However, SSR does have its limitations. Because each page is generated on the server, it can be more resource-intensive, especially for websites with a large number of pages or complex content. Additionally, interactivity may be limited compared to client-side rendering, as the server generates static HTML without the ability to execute client-side JavaScript.

Hydration is a key concept in web development, allowing for dynamic and interactive user experiences on the server. By understanding how hydration works in SSR, developers can build web applications that are fast, responsive, and accessible to a wide range of users.

Problem Hydration Solves

Hydration in web development, particularly in the context of meta-frameworks, addresses a fundamental challenge encountered in Server-Side Rendering (SSR). Here's a closer look at the problem hydration solves:

When a web page is rendered server-side, it typically results in a static HTML page being sent to the user's browser. While this approach ensures fast initial page loads and better SEO, it lacks the interactivity and dynamic behavior expected in modern web applications.

In SSR, the initial HTML page lacks the necessary JavaScript event handlers and other client-side logic needed for interactivity. This means that although the page may look visually complete, it lacks the underlying functionality that users expect, such as interactive forms, dynamic content updates, or real-time data fetching.

This deficiency becomes apparent when users try to interact with the page elements, expecting them to respond dynamically. However, without the requisite JavaScript functionality attached to these elements, they remain static and non-responsive.

Here's where hydration comes in: it bridges the gap between the initial static HTML page generated by SSR and the dynamic behavior expected in modern web applications. Hydration essentially involves attaching client-side JavaScript event handlers to the HTML elements already rendered on the server.

By "hydrating" the static HTML with JavaScript functionality on the client-side, the web page becomes interactive and responsive. This means that users can interact with the page elements as expected, triggering events, fetching data, and updating the UI dynamicall all without the need for a full page reload.

Drawbacks of Hydration

Until now you might be thinking of hydration a quite good concept having less drawbacks & considerations. Well you are right, following are the set of drawbacks & considerations that comes with hydration.

1. Increased Initial Load Time

Hydration adds additional JavaScript execution and processing time to the initial page load. This can potentially slow down the time it takes for the page to become fully interactive,

2. Complexity and Overhead

Implementing hydration requires careful management of both server-side and client-side code. Developers need to ensure that the server-rendered HTML and client-side JavaScript remain synchronized.

3. Code Duplication

With hydration, developers may find themselves duplicating logic between the server and client environments to ensure consistent behavior.

Overall, while hydration offers significant benefits in terms of improved interactivity and user experience, it's essential for developers to carefully consider and mitigate the potential drawbacks to ensure optimal performance, maintainability, and compatibility of their web applications.

Is Hydration the optimal solution ?

I have came accross one blog published by thenewstack.io. In this blog they are highlighed the problems which one can occur if they are relying on the hydration. They have also suggested the alternatives of hydration that one should focus on i.e. Resumibility & Island architecture.

You should read this blog if you want in detail explainatio of how things work.

According to me, they are not alternatives to each other. Instead, they address different aspects of web development and computing in general.

Lets talk about this in the upcoming blog post.

I think Hydration is the best solution for the problem it is serving. If you have build application over the SSR meta frameworks such as Next.js you would have realised how fast page render can be. In fact you are viewing this website which is built in next.js itself.

Conclusion

Hydration stands as the key to unlocking dynamic web experiences, seamlessly blending server-side rendering's speed with client-side interactivity. I bet in coming updates meta-frameworks will focus on hydration techniques.

I hope you would love this blog post. It had taken me a week and hours of research to design and publish content.

Keep supporting to see such valuable content coming forward.

See you soon, Keep coding

Yours Devesh Korde