Mastering REST Parameters in SvelteKit

In SvelteKit, REST parameters allow you to capture dynamic segments of a URL in your routes. This feature enables the creation of flexible endpoints that can handle multiple variations of a URL effectively.

Key Concepts

• REST Parameters: These segments of a URL can change and are represented by a dot ... in the route file name.
• Dynamic Routing: With REST parameters, you can create routes that respond to different input values without needing to define a separate route for each possibility.

How to Use REST Parameters

1. Creating a Route with REST Params:
   • Define a route in your SvelteKit application by adding a file with the name format [...params].svelte or [...params].js in the src/routes directory.
2. Accessing REST Params:
   • Inside your Svelte component, access the captured parameters using the params object.
3. URL Structure:
   • If a user navigates to /blog/my-first-post, the slug will capture ['blog', 'my-first-post'].
   • If a user navigates to /products/electronics/phones, the slug will capture ['products', 'electronics', 'phones'].

Example:

export async function load({ params }) {
  const { slug } = params; // slug will contain the captured segments of the URL
  // You can use slug to fetch data or render content dynamically
}

Example:

src/routes/[...slug].svelte

Example

Here's a simple example to illustrate the concept:

File Structure:

src/
└── routes/
    └── [...slug].svelte

Code in [...slug].svelte:

<script context="module">
  export async function load({ params }) {
    const { slug } = params;  // slug will be an array of URL segments
    return {
      props: {
        slug // Pass slug to the component
      }
    };
  }
</script>

<script>
  export let slug;
</script>

<h1>Dynamic Route</h1>
<p>The slug is: {slug.join('/')}</p>

Result:

Navigating to /about/team would display:

The slug is: about/team

Conclusion

REST parameters in SvelteKit allow you to create dynamic and flexible routes that can capture multiple URL segments. By using the params object, you can easily access and utilize these segments in your application, simplifying the process of building complex routing structures.