Nuxt/docs/1.getting-started/9.prerendering.md

194 lines
5.5 KiB
Markdown

---
title: "Prerendering"
description: Nuxt allows pages to be statically rendered at build time to improve certain performance or SEO metrics
navigation.icon: i-ph-code-block
---
Nuxt allows for select pages from your application to be rendered at build time. Nuxt will serve the prebuilt pages when requested instead of generating them on the fly.
:read-more{title="Nuxt rendering modes" to="/docs/guide/concepts/rendering"}
## Crawl-based Pre-rendering
Use the [`nuxi generate` command](/docs/api/commands/generate) to build and pre-render your application using the [Nitro](/docs/guide/concepts/server-engine) crawler. This command is similar to `nuxt build` with the `nitro.static` option set to `true`, or running `nuxt build --prerender`.
This will build your site, stand up a nuxt instance, and, by default, prerender the root page `/` along with any of your site's pages it links to, any of your site's pages they link to, and so on.
::package-managers
```bash [npm]
npx nuxi generate
```
```bash [yarn]
yarn dlx nuxi generate
```
```bash [pnpm]
pnpm dlx nuxi generate
```
```bash [bun]
bun x nuxi generate
```
::
You can now deploy the `.output/public` directory to any static hosting service or preview it locally with `npx serve .output/public`.
Working of the Nitro crawler:
1. Load the HTML of your application's root route (`/`), any non-dynamic pages in your `~/pages` directory, and any other routes in the `nitro.prerender.routes` array.
2. Save the HTML and `payload.json` to the `~/.output/public/` directory to be served statically.
3. Find all anchor tags (`<a href="...">`) in the HTML to navigate to other routes.
4. Repeat steps 1-3 for each anchor tag found until there are no more anchor tags to crawl.
This is important to understand since pages that are not linked to a discoverable page can't be pre-rendered automatically.
::read-more{to="/docs/api/commands/generate#nuxi-generate"}
Read more about the `nuxi generate` command.
::
### Selective Pre-rendering
You can manually specify routes that [Nitro](/docs/guide/concepts/server-engine) will fetch and pre-render during the build or ignore routes that you don't want to pre-render like `/dynamic` in the `nuxt.config` file:
```ts twoslash [nuxt.config.ts]
export default defineNuxtConfig({
nitro: {
prerender: {
routes: ["/user/1", "/user/2"],
ignore: ["/dynamic"],
},
},
});
```
You can combine this with the `crawlLinks` option to pre-render a set of routes that the crawler can't discover like your `/sitemap.xml` or `/robots.txt`:
```ts twoslash [nuxt.config.ts]
export default defineNuxtConfig({
nitro: {
prerender: {
crawlLinks: true,
routes: ["/sitemap.xml", "/robots.txt"],
},
},
});
```
Setting `nitro.prerender` to `true` is similar to `nitro.prerender.crawlLinks` to `true`.
::read-more{to="https://nitro.unjs.io/config#prerender"}
Read more about pre-rendering in the Nitro documentation.
::
Lastly, you can manually configure this using routeRules.
```ts twoslash [nuxt.config.ts]
export default defineNuxtConfig({
routeRules: {
// Set prerender to true to configure it to be prerendered
"/rss.xml": { prerender: true },
// Set it to false to configure it to be skipped for prerendering
"/this-DOES-NOT-get-prerendered": { prerender: false },
// Everything under /blog gets prerendered as long as it
// is linked to from another page
"/blog/**": { prerender: true },
},
});
```
::read-more{to="https://nitro.unjs.io/config/#routerules"}
Read more about Nitro's `routeRules` configuration.
::
As a shorthand, you can also configure this in a page file using [`defineRouteRules`](/docs/api/utils/define-route-rules).
::read-more{to="/docs/guide/going-further/experimental-features#inlinerouterules" icon="i-ph-star"}
This feature is experimental and in order to use it you must enable the `experimental.inlineRouteRules` option in your `nuxt.config`.
::
```vue [pages/index.vue]
<script setup>
// Or set at the page level
defineRouteRules({
prerender: true,
});
</script>
<template>
<div>
<h1>Homepage</h1>
<p>Pre-rendered at build time</p>
</div>
</template>
```
This will be translated to:
```ts [nuxt.config.ts]
export default defineNuxtConfig({
routeRules: {
"/": { prerender: true },
},
});
```
## Runtime prerender configuration
### `prerenderRoutes`
You can use this at runtime within a [Nuxt context](/docs/guide/going-further/nuxt-app#the-nuxt-context) to add more routes for Nitro to prerender.
```vue [pages/index.vue]
<script setup>
prerenderRoutes(["/some/other/url"]);
</script>
<template>
<div>
<h1>This will register other routes for prerendering when prerendered</h1>
</div>
</template>
```
:read-more{title="prerenderRoutes" to="/docs/api/utils/prerender-routes"}
### `prerender:routes` Nuxt hook
This is called before prerendering for additional routes to be registered.
```ts [nitro.config.ts]
export default defineNuxtConfig({
hooks: {
async "prerender:routes"(ctx) {
const { pages } = await fetch("https://api.some-cms.com/pages").then(
(res) => res.json(),
);
for (const page of pages) {
ctx.routes.add(`/${page.name}`);
}
},
},
});
```
### `prerender:generate` Nitro hook
This is called for each route during prerendering. You can use this for fine grained handling of each route that gets prerendered.
```ts [nitro.config.ts]
export default defineNuxtConfig({
nitro: {
hooks: {
"prerender:generate"(route) {
if (route.route?.includes("private")) {
route.skip = true;
}
},
},
},
});
```