Introduction to getStaticPaths
In Next.js, getStaticPaths is used to create static pages that require dynamic routing. This capability allows us to create different pages based on different parameters without needing to render on the server every time. With getStaticPaths, we can generate static pages in advance during the build process.
As an example, suppose you have a blogging website that has a separate page for each post. Using getStaticPaths, you can create a dynamic route for each post, so users can access different pages.
Since the pages created with getStaticPaths are static, this method can speed up loading times and improve user experience. This is because these pages were created beforehand on the server and do not require further rendering for each request.
How to Use getStaticPaths
To use getStaticPaths, you need to define a function with this name in your page file. This function will return a list of possible paths and tell Next.js which pages to create at build time.
One of the important points in getStaticPaths is to specify the parameters. You need to indicate which parameters should be returned for each path. This operation helps Next.js know which pages to generate at build time.
export async function getStaticPaths() {\r\n const res = await fetch('https://example.com/api/posts');\r\n const posts = await res.json();\r\n\r\n const paths = posts.map((post) => ({\r\n params: { id: post.id.toString() },\r\n }));\r\n\r\n return { paths, fallback: false };\r\n}Line-by-Line Explanation
export async function getStaticPaths()This line defines an asynchronous function named getStaticPaths that will be used to fetch possible static paths.
const res = await fetch('https://example.com/api/posts');This makes an HTTP request to the specified address to fetch the necessary data.
const posts = await res.json();This converts the received data into JSON format and stores it in the variable posts.
const paths = posts.map((post) => ({ params: { id: post.id.toString() }, }));For each post, a path with the parameter id is created. These paths are based on the ids of the posts.
return { paths, fallback: false };This returns a list of created paths so that Next.js can generate the static pages during build time. The fallback parameter determines whether to return a 404 error for missing pages or not.