---
id: gh-clerk-astro-patterns
name: "clerk-astro-patterns"
url: https://skills.yangsir.net/skill/gh-clerk-astro-patterns
author: clerk
domain: ai-app-building-integration
tags: ["clerk", "astro", "authentication", "web-development", "ssr"]
install_count: 14200
rating: 4.50 (120 reviews)
github: https://github.com/clerk/skills/tree/main/skills/frameworks/clerk-astro-patterns
---

# clerk-astro-patterns

> 此技能为Astro应用集成Clerk认证提供了最佳实践和模式。它涵盖了中间件、SSR页面和岛屿组件中的认证实现，确保在不同渲染模式下安全无缝的用户认证，帮助开发者快速构建健壮的认证解决方案。

**Stats**: 14,200 installs · 4.5/5 (120 reviews)

## Before / After 对比

### 解决Astro生产环境认证问题

**Before**:

在开发环境中，Clerk认证功能正常，但在部署到生产环境后，用户认证失效，导致应用无法正常访问受保护的页面，需要耗费大量时间排查配置问题，通常需要数小时。

**After**:

通过遵循Clerk Astro模式，明确配置`output: 'server'`或`hybrid`，确保生产环境下的SSR页面能够正确处理认证逻辑，将认证问题排查时间从数小时缩短到几分钟，显著提升部署效率。

| Metric | Before | After | Change |
|---|---|---|---|
| 认证问题排查时间 | 240分钟 | 15分钟 | -93.75% |

## Readme

# Astro Patterns

SDK: `@clerk/astro` v3+. Requires Astro 4.15+.

## What Do You Need?

| Task | Reference |
|------|-----------|
| Configure middleware | references/middleware.md |
| Protect SSR pages | references/ssr-pages.md |
| Use Clerk in island components | references/island-components.md |
| Auth in API routes | references/api-routes.md |
| Use Clerk with React in Astro | references/astro-react.md |

## Mental Model

Astro has two rendering modes per page: **SSR** and **static prerender**. Clerk works differently in each:

- **SSR pages** — use `Astro.locals.auth()` which is populated by the middleware
- **Static pages** (`export const prerender = true`) — Clerk middleware skips them; use client-side hooks in islands
- **Islands** — React/Vue/Svelte components; use `useAuth()` and other hooks from `@clerk/astro/react`

```
Request → clerkMiddleware() → SSR page → Astro.locals.auth()
                                ↓
                         Island (.client) → useAuth() hook
```

## Setup

### astro.config.mjs

```ts
import { defineConfig } from 'astro/config'
import clerk from '@clerk/astro'

export default defineConfig({
  integrations: [clerk()],
  output: 'server',
})
```

### src/middleware.ts

```ts
import { clerkMiddleware, createRouteMatcher } from '@clerk/astro/server'

const isProtectedRoute = createRouteMatcher(['/dashboard(.*)'])

export const onRequest = clerkMiddleware((auth, context, next) => {
  if (isProtectedRoute(context.request) && !auth().userId) {
    return auth().redirectToSignIn()
  }
  return next()
})
```

## SSR Page Auth

```astro
---
const { userId, orgId } = Astro.locals.auth()
if (!userId) return Astro.redirect('/sign-in')
---

<h1>Dashboard</h1>
```

## Common Pitfalls

| Symptom | Cause | Fix |
|---------|-------|-----|
| `Astro.locals.auth` is undefined | Missing middleware | Add `clerkMiddleware` to `src/middleware.ts` |
| Auth works in dev but not production | `output: 'static'` globally | Set `output: 'server'` or `hybrid` for protected pages |
| Static page has no auth | Prerendered pages skip middleware | Use `export const prerender = false` or move to island |
| Island not reactive to sign-in | Missing `client:load` directive | Add `client:load` to the island component |

## Import Map

| What | Import From |
|------|-------------|
| `clerkMiddleware`, `createRouteMatcher` | `@clerk/astro/server` |
| `useAuth`, `useUser`, `UserButton` | `@clerk/astro/react` |
| Astro components (`<SignIn>`, etc.) | `@clerk/astro/components` |

## Env Variables

```
# .env
PUBLIC_CLERK_PUBLISHABLE_KEY=pk_...
CLERK_SECRET_KEY=sk_...
```

Astro uses `PUBLIC_` prefix for client-exposed variables (not `NEXT_PUBLIC_`).

## See Also

- `clerk-setup` - Initial Clerk install
- `clerk-custom-ui` - Custom flows & appearance
- `clerk-orgs` - B2B organizations

## Docs

[Astro SDK](https://clerk.com/docs/astro/getting-started/quickstart)


---
*Source: https://skills.yangsir.net/skill/gh-clerk-astro-patterns*
*Markdown mirror: https://skills.yangsir.net/api/skill/gh-clerk-astro-patterns/markdown*