Routing
Astro uses file-based routing to generate your build URLs based on the file layout of your project src/pages/
directory.
Navigating between pages
Section titled Navigating between pagesAstro uses standard HTML <a>
elements to navigate between routes. There is no framework-specific <Link>
component provided.
Static routes
Section titled Static routes.astro
page components as well as Markdown and MDX Files (.md
, .mdx
) within the src/pages/
directory automatically become pages on your website. Each page’s route corresponds to its path and filename within the src/pages/
directory.
There is no separate “routing config” to maintain in an Astro project! When you add a file to the src/pages/
directory, a new route is automatically created for you. In static builds, you can customize the file output format using the build.format
configuration option.
Dynamic routes
Section titled Dynamic routesAn Astro page file can specify dynamic route parameters in its filename to generate multiple, matching pages. For example, src/pages/authors/[author].astro
generates a bio page for every author on your blog. author
becomes a parameter that you can access from inside the page.
In Astro’s default static output mode, these pages are generated at build time, and so you must predetermine the list of author
s that get a corresponding file. In SSR mode, a page will be generated on request for any route that matches.
Static (SSG) Mode
Section titled Static (SSG) ModeBecause all routes must be determined at build time, a dynamic route must export a getStaticPaths()
that returns an array of objects with a params
property. Each of these objects will generate a corresponding route.
[dog].astro
defines the dynamic dog
parameter in its filename, so the objects returned by getStaticPaths()
must include dog
in their params
. The page can then access this parameter using Astro.params
.
This will generate three pages: /dogs/clifford
, /dogs/rover
, and /dogs/spot
, each displaying the corresponding dog name.
The filename can include multiple parameters, which must all be included in the params
objects in getStaticPaths()
:
This will generate /en-v1/info
and /fr-v2/info
.
Parameters can be included in separate parts of the path. For example, the file src/pages/[lang]/[version]/info.astro
with the same getStaticPaths()
above will generate the routes /en/v1/info
and /fr/v2/info
.
Decoding params
Section titled Decoding paramsThe params
provided to the function getStaticPaths()
function are not decoded. Use the function decodeURI
when you need to decode parameter values.
getStaticPaths()
.
Rest parameters
Section titled Rest parametersIf you need more flexibility in your URL routing, you can use a rest parameter ([...path]
) in your .astro
filename to match file paths of any depth:
This will generate /sequences/one/two/three
, /sequences/four
, and /sequences
. (Setting the rest parameter to undefined
allows it to match the top level page.)
Rest parameters can be used with other named parameters. For example, GitHub’s file viewer can be represented with the following dynamic route:
In this example, a request for /withastro/astro/tree/main/docs/public/favicon.svg
would be split into the following named parameters:
Example: Dynamic pages at multiple levels
Section titled Example: Dynamic pages at multiple levelsIn the following example, a rest parameter ([...slug]
) and the props
feature of getStaticPaths()
generate pages for slugs of different depths.
Server (SSR) Mode
Section titled Server (SSR) ModeIn SSR mode, dynamic routes are defined the same way: include [param]
or [...path]
brackets in your file names to match arbitrary strings or paths. But because the routes are no longer built ahead of time, the page will be served to any matching route. Since these are not “static” routes, getStaticPaths
should not be used.
This page will be served for any value of resource
and id
: resources/users/1
, resources/colors/blue
, etc.
Modifying the [...slug]
example for SSR
Section titled Modifying the [...slug] example for SSRBecause SSR pages can’t use getStaticPaths()
, they can’t receive props. The previous example can be adapted for SSR mode by looking up the value of the slug
param in an object. If the route is at the root (”/”), the slug param will be undefined
. If the value doesn’t exist in the object, we redirect to a 404 page.
Redirects
Section titled RedirectsSometimes you will need to redirect your readers to a new page, either permanently because your site structure has changed or in response to an action such as logging in to an authenticated route.
You can define rules to redirect users to permanently-moved pages in your Astro config. Or, redirect users dynamically as they use your site.
Configured Redirects
Section titled Configured Redirects
Added in:
astro@2.9.0
You can specify a mapping of permanent redirects in your Astro config with the redirects
value. For most redirects, this is a mapping of an old route to the new route:
These redirects follow the same priority rules as file-based routes and will always take lower precedence than an existing page file of the same name in your project. For example, /old-page
will not redirect to /new-page
if your project contains the file src/pages/old-page.astro
.
Dynamic routes are allowed as long as both the new and old routes contain the same parameters, for example:
Using SSR or a static adapter, you can also provide an object as the value, allowing you to specify the status
code in addition to the new destination
:
When running astro build
, Astro will output HTML files with the meta refresh tag by default. Supported adapters will instead write out the host’s configuration file with the redirects.
The status code is 301
by default. If building to HTML files the status code is not used by the server.
Dynamic redirects
Section titled Dynamic redirectsOn the Astro
global, the Astro.redirect
method allows you to redirect to another page dynamically. You might do this after checking if the user is logged in by getting their session from a cookie.
Rewrites
Section titled Rewrites
Added in:
astro@4.13.0
A rewrite allows you to serve a different route without redirecting the browser to a different page. The browser will show the original address in the URL bar, but will instead display the content of the URL provided to Astro.rewrite()
.
For content that has permanently moved, or to direct your user to a different page with a new URL (e.g. a user dashboard after logging in), use a redirect instead.
Rewrites can be useful for showing the same content at multiple paths (e.g. /products/shoes/men/
and /products/men/shoes/
) without needing to maintain two different source files.
Rewrites are also useful for SEO purposes and user experience. They allow you to display content that otherwise would require redirecting your visitor to a different page or would return a 404 status. One common use of rewrites is to show the same localized content for different variants of a language.
The following example uses a rewrite to render the /es/
version of a page when the /es-CU/
(Cuban Spanish) URL path is visited. When a visitor navigates to the URL /es-cu/articles/introduction
, Astro will render the content generated by the file src/pages/es/articles/introduction.astro
.
Use context.rewrite()
in your endpoint files to reroute to a different page:
If the URL passed to Astro.rewrite()
emits a runtime error, Astro will show the overlay error in development and return a 500 status code in production. If the URL does not exist in your project, a 404 status code will be returned.
You can intentionally create a rewrite to render your /404
page, for example to indicate that a product in your e-commerce shop is no longer available:
You can also conditionally rewrite based on an HTTP response status, for example to display a certain page on your site when visiting a URL that doesn’t exist:
Before displaying the content from the specified rewrite path, the function Astro.rewrite()
will trigger a new, complete rendering phase. This re-executes any middleware for the new route/request.
Astro.rewrite()
API reference for more information.
Route Priority Order
Section titled Route Priority OrderIt’s possible for multiple defined routes to attempt to build the same URL path. For example, all of these routes could build /posts/create
:
Directorysrc/pages/
- […slug].astro
Directoryposts/
- create.astro
- [page].astro
- [pid].ts
- […slug].astro
Astro needs to know which route should be used to build the page. To do so, it sorts them according to the following rules in order:
- Astro reserved routes
- Routes with more path segments will take precedence over less specific routes. In the example above, all routes under
/posts/
take precedence over/[...slug].astro
at the root. - Static routes without path parameters will take precedence over dynamic routes. E.g.
/posts/create.astro
takes precedence over all the other routes in the example. - Dynamic routes using named parameters take precedence over rest parameters. E.g.
/posts/[page].astro
takes precedence over/posts/[...slug].astro
. - Pre-rendered dynamic routes take precedence over server dynamic routes.
- Endpoints take precedence over pages.
- File-based routes take precedence over redirects.
- If none of the rules above decide the order, routes are sorted alphabetically based on the default locale of your Node installation.
Given the example above, here are a few examples of how the rules will match a requested URL to the route used to build the HTML:
pages/posts/create.astro
- Will build only/posts/create
pages/posts/[pid].ts
- Will build/posts/abc
,/posts/xyz
, etc. But not/posts/create
pages/posts/[page].astro
- Will build/posts/1
,/posts/2
, etc. But not/posts/create
,/posts/abc
nor/posts/xyz
pages/posts/[...slug].astro
- Will build/posts/1/2
,/posts/a/b/c
, etc. But not/posts/create
,/posts/1
,/posts/abc
, etc.pages/[...slug].astro
- Will build/abc
,/xyz
,/abc/xyz
, etc. But not/posts/create
,/posts/1
,/posts/abc
, , etc.
Reserved routes
Section titled Reserved routesInternal routes take priority over any user-defined or integration-defined routes as they are required for Astro features to work. The following are Astro’s reserved routes:
_astro/
: Serves all of the static assets to the client, including CSS documents, bundled client scripts, optimized images, and any Vite assets._server_islands/
: Serves the dynamic components deferred into a server island._actions/
: Serves any defined actions.
Pagination
Section titled PaginationAstro supports built-in pagination for large collections of data that need to be split into multiple pages. Astro will generate common pagination properties, including previous/next page URLs, total number of pages, and more.
Paginated route names should use the same [bracket]
syntax as a standard dynamic route. For instance, the file name /astronauts/[page].astro
will generate routes for /astronauts/1
, /astronauts/2
, etc, where [page]
is the generated page number.
You can use the paginate()
function to generate these pages for an array of values like so:
This generates the following pages, with 2 items to a page:
/astronauts/1
- Page 1: Displays “Neil Armstrong” and “Buzz Aldrin”/astronauts/2
- Page 2: Displays “Sally Ride” and “John Glenn”
The page
prop
Section titled The page propWhen you use the paginate()
function, each page will be passed its data via a page
prop. The page
prop has many useful properties that you can use to build pages and links between them:
The following example displays current information for the page along with links to navigate between pages:
page
prop.
Nested Pagination
Section titled Nested PaginationA more advanced use-case for pagination is nested pagination. This is when pagination is combined with other dynamic route params. You can use nested pagination to group your paginated collection by some property or tag.
For example, if you want to group your paginated Markdown posts by some tag, you would use nested pagination by creating a /src/pages/[tag]/[page].astro
page that would match the following URLS:
/red/1
(tag=red)/red/2
(tag=red)/blue/1
(tag=blue)/green/1
(tag=green)
Nested pagination works by returning an array of paginate()
results from getStaticPaths()
, one for each grouping.
In the following example, we will implement nested pagination to build the URLs listed above:
Excluding pages
Section titled Excluding pagesYou can exclude pages or directories within src/pages
from being built by prefixing their names with an underscore (_
). Files with the _
prefix won’t be recognized by the router and won’t be placed into the dist/
directory.
You can use this to temporarily disable pages, and also to put tests, utilities, and components in the same folder as their related pages.
In this example, only src/pages/index.astro
and src/pages/projects/project1.md
will be built as page routes and HTML files.
Directorysrc/pages/
Directory_hidden-directory/
- page1.md
- page2.md
- _hidden-page.astro
- index.astro
Directoryprojects/
- _SomeComponent.astro
- _utils.js
- project1.md