Astro Global Object

API reference for the Astro global object available in .astro files

The Astro global object is available in all .astro components and provides access to request data, routing information, and utilities for rendering.

Properties

Astro.props · Record<string, any>

Component props passed from parent components or from getStaticPaths().

---
// MyComponent.astro
const { title, description } = Astro.props;
---
<h1>{title}</h1>
<p>{description}</p>

Astro.request · Request

A standard Request object containing information about the current request.

---
const userAgent = Astro.request.headers.get('user-agent');
const method = Astro.request.method;
---

Astro.url · URL

A URL object constructed from the current request URL. Equivalent to new URL(Astro.request.url).

---
const pathname = Astro.url.pathname;
const searchParams = Astro.url.searchParams;
const origin = Astro.url.origin;
---
<p>Current path: {pathname}</p>

Astro.params · Record<string, string | undefined>

An object containing the values of dynamic route segments matched for this request.

---
// src/pages/blog/[slug].astro
const { slug } = Astro.params;
---
<h1>Post: {slug}</h1>

Astro.site · URL | undefined

The site from your Astro config, parsed as a URL instance. Returns undefined if not set.

---
const siteUrl = Astro.site;
---
<link rel="canonical" href={new URL(Astro.url.pathname, Astro.site)} />

Astro.generator · string

A string representing the Astro version, in the format "Astro v5.x.x".

<meta name="generator" content={Astro.generator} />

Astro.cookies · AstroCookies

Utilities for reading and manipulating cookies in on-demand routes.

---
const sessionId = Astro.cookies.get('session');
Astro.cookies.set('theme', 'dark', {
  path: '/',
  maxAge: 60 * 60 * 24 * 7 // 1 week
});
---

Astro.locals · App.Locals

An object that middleware can use to store extra information related to the request.

---
// Access value set in middleware
const user = Astro.locals.user;
---
<p>Welcome, {user.name}!</p>

Astro.clientAddress · string

The IP address of the client making the request. Only available in on-demand routes.

---
const ip = Astro.clientAddress;
---

Astro.response · ResponseInit & { readonly headers: Headers }

A standard ResponseInit object for modifying the outgoing response.

---
Astro.response.status = 404;
Astro.response.headers.set('X-Custom-Header', 'value');
---

Astro.self · AstroComponentFactory

Allows a component to recursively call itself.

---
const { items } = Astro.props;
---
<ul>
  {items.map((item) => (
    <li>
      {Array.isArray(item) ? (
        <Astro.self items={item} />
      ) : (
        item
      )}
    </li>
  ))}
</ul>

Astro.slots · object

An object containing utility functions for working with slotted children.

Methods

Astro.slots.has · (slotName: string) => boolean

Check whether content for a slot name exists.

---
const hasHeader = Astro.slots.has('header');
---
{hasHeader && <header><slot name="header" /></header>}
<slot />

Astro.slots.render · (slotName: string, args?: any[]) => Promise<string>

Asynchronously renders the contents of a slot to a string of HTML.

---
let html = '';
if (Astro.slots.has('default')) {
  html = await Astro.slots.render('default');
}
---
<Fragment set:html={html} />

Astro.currentLocale · string | undefined

The current locale computed from the URL of the request. Only available when i18n routing is configured.

---
const locale = Astro.currentLocale; // 'en', 'fr', etc.
---

Astro.preferredLocale · string | undefined

The best match between visitor’s browser language preferences and supported locales. Only available in on-demand routes.

---
const preferred = Astro.preferredLocale;
---

Astro.preferredLocaleList · string[] | undefined

List of all locales that are both requested by the browser and supported by the site. Only available in on-demand routes.

---
const locales = Astro.preferredLocaleList;
---

Astro.isPrerendered · boolean

Whether the current route is prerendered or not.

---
if (!Astro.isPrerendered) {
  // Use on-demand features
}
---

Astro.routePattern · string

The route pattern for the current route, stripped of the srcDir and pages folder.

---
// src/pages/index.astro -> '/'
// src/pages/blog/[slug].astro -> '/blog/[slug]'
const pattern = Astro.routePattern;
---

Astro.originPathname · string

The original pathname before any rewrites were applied. Useful for tracking the original URL.

---
const original = Astro.originPathname;
const current = Astro.url.pathname;
---

Methods

Astro.redirect · (path: string, status?: number) => Response

Create a response that redirects to another page.

---
import type { APIContext } from 'astro';

export function GET({ redirect }: APIContext) {
  return redirect('/login', 302);
}
---

Astro.rewrite · (rewritePayload: RewritePayload) => Promise<Response>

Serve content from a different URL or path without redirecting the browser.

---
export async function GET(context) {
  return context.rewrite('/new-page');
}
---

Astro.callAction · <TAction>(action: TAction, input: Parameters<TAction>[0]) => Promise<ActionReturnType<TAction>>

Call an Action handler directly from your Astro component.

---
import { actions } from 'astro:actions';

const result = await Astro.callAction(actions.getPost, { postId: 'test' });
---

Astro.getActionResult · <TAction>(action: TAction) => ActionReturnType<TAction> | undefined

Get the result of an Action submission when using a form POST.

---
import { actions } from 'astro:actions';

const result = Astro.getActionResult(actions.myAction);
---
{result?.data && <p>Success: {result.data}</p>}
{result?.error && <p>Error: {result.error.message}</p>}

Session

Astro.session · AstroSession | undefined

Utilities for handling sessions in on-demand rendered routes.

---
// Get session data
const userId = await Astro.session.get('userId');

// Set session data
await Astro.session.set('userId', '123');

// Destroy session
await Astro.session.destroy();
---

CSP (Content Security Policy)

Astro.csp · object | undefined

Utilities to control CSP headers. Only available when CSP is enabled in config.

Methods

Astro.csp.insertDirective · (directive: string) => void

Add a specific CSP directive to the route being rendered.

---
Astro.csp?.insertDirective("default-src 'self' https://example.com");
---

Astro.csp.insertStyleResource · (payload: string) => void

Set the resource for the style-src directive.

---
Astro.csp?.insertStyleResource('https://styles.cdn.example.com/');
---

Astro.csp.insertStyleHash · (hash: string) => void

Insert a single style hash to the route being rendered.

---
Astro.csp?.insertStyleHash('sha256-1234567890abcdef');
---

Astro.csp.insertScriptResource · (resource: string) => void

Set the resource for the script-src directive.

---
Astro.csp?.insertScriptResource('https://scripts.cdn.example.com/');
---

Astro.csp.insertScriptHash · (hash: string) => void

Insert a single script hash to the route being rendered.

---
Astro.csp?.insertScriptHash('sha256-1234567890abcdef');
---