Fresh Framework with Deno | Google Antigravity Directory

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# Fresh Framework with Deno

You are an expert in Fresh, the next-generation web framework for Deno with islands architecture and zero runtime overhead by default.

## Key Principles
- Use Deno runtime for TypeScript-first development
- Leverage islands for selective client-side interactivity
- Write routes and handlers with file-based routing
- Use Preact for component rendering
- Deploy seamlessly to Deno Deploy

## Project Structure
```
my-fresh-app/
├── deno.json              # Deno configuration
├── fresh.gen.ts           # Generated manifest
├── main.ts                # Entry point
├── dev.ts                 # Dev server
├── routes/
│   ├── _app.tsx           # App wrapper
│   ├── _layout.tsx        # Layout component
│   ├── _middleware.ts     # Route middleware
│   ├── index.tsx          # / route
│   ├── about.tsx          # /about route
│   ├── blog/
│   │   ├── index.tsx      # /blog
│   │   └── [slug].tsx     # /blog/:slug
│   └── api/
│       └── users.ts       # /api/users
├── islands/
│   ├── Counter.tsx        # Interactive island
│   └── SearchBar.tsx
├── components/
│   ├── Header.tsx         # Static component
│   └── Footer.tsx
├── static/
│   └── styles.css
└── utils/
    └── db.ts
```

## Route Handlers
```tsx
// routes/blog/[slug].tsx
import { Handlers, PageProps } from "$fresh/server.ts";
import { Head } from "$fresh/runtime.ts";
import { db } from "../../utils/db.ts";
import Comments from "../../islands/Comments.tsx";

interface Post {
  slug: string;
  title: string;
  content: string;
  publishedAt: Date;
}

interface Data {
  post: Post;
}

export const handler: Handlers<Data> = {
  async GET(req, ctx) {
    const { slug } = ctx.params;
    
    const post = await db.posts.findBySlug(slug);
    
    if (!post) {
      return ctx.renderNotFound();
    }
    
    return ctx.render({ post });
  },
  
  async POST(req, ctx) {
    const form = await req.formData();
    const comment = form.get("comment")?.toString();
    
    if (!comment || comment.length < 3) {
      return new Response("Comment too short", { status: 400 });
    }
    
    await db.comments.create({
      postSlug: ctx.params.slug,
      content: comment,
    });
    
    // Redirect back to post
    return new Response("", {
      status: 303,
      headers: { Location: `/blog/${ctx.params.slug}` },
    });
  },
};

export default function BlogPost({ data }: PageProps<Data>) {
  const { post } = data;
  
  return (
    <>
      <Head>
        <title>{post.title} | My Blog</title>
        <meta name="description" content={post.content.slice(0, 160)} />
      </Head>
      
      <article>
        <h1>{post.title}</h1>
        <time>{post.publishedAt.toLocaleDateString()}</time>
        <div dangerouslySetInnerHTML={{ __html: post.content }} />
      </article>
      
      {/* Interactive island for comments */}
      <Comments postSlug={post.slug} />
    </>
  );
}
```

## Islands (Interactive Components)
```tsx
// islands/Counter.tsx
import { useSignal } from "@preact/signals";

interface CounterProps {
  initialCount?: number;
  step?: number;
}

export default function Counter({ initialCount = 0, step = 1 }: CounterProps) {
  const count = useSignal(initialCount);
  
  return (
    <div class="counter">
      <p>Count: {count.value}</p>
      <button onClick={() => count.value -= step}>-{step}</button>
      <button onClick={() => count.value += step}>+{step}</button>
      <button onClick={() => count.value = initialCount}>Reset</button>
    </div>
  );
}

// islands/SearchBar.tsx
import { useSignal } from "@preact/signals";
import { useEffect } from "preact/hooks";

interface SearchResult {
  id: string;
  title: string;
  url: string;
}

export default function SearchBar() {
  const query = useSignal("");
  const results = useSignal<SearchResult[]>([]);
  const loading = useSignal(false);
  
  useEffect(() => {
    if (query.value.length < 2) {
      results.value = [];
      return;
    }
    
    const controller = new AbortController();
    loading.value = true;
    
    fetch(`/api/search?q=${encodeURIComponent(query.value)}`, {
      signal: controller.signal,
    })
      .then((res) => res.json())
      .then((data) => {
        results.value = data;
        loading.value = false;
      })
      .catch((e) => {
        if (e.name !== "AbortError") {
          loading.value = false;
        }
      });
    
    return () => controller.abort();
  }, [query.value]);
  
  return (
    <div class="search">
      <input
        type="search"
        value={query.value}
        onInput={(e) => query.value = e.currentTarget.value}
        placeholder="Search..."
      />
      
      {loading.value && <span>Loading...</span>}
      
      {results.value.length > 0 && (
        <ul class="results">
          {results.value.map((result) => (
            <li key={result.id}>
              <a href={result.url}>{result.title}</a>
            </li>
          ))}
        </ul>
      )}
    </div>
  );
}
```

## Middleware
```tsx
// routes/_middleware.ts
import { FreshContext } from "$fresh/server.ts";

interface State {
  user: { id: string; name: string } | null;
  startTime: number;
}

export async function handler(
  req: Request,
  ctx: FreshContext<State>,
) {
  // Add timing
  ctx.state.startTime = performance.now();
  
  // Authentication
  const sessionId = getCookie(req.headers, "session");
  if (sessionId) {
    ctx.state.user = await validateSession(sessionId);
  }
  
  // Continue to route handler
  const response = await ctx.next();
  
  // Add headers
  const duration = performance.now() - ctx.state.startTime;
  response.headers.set("X-Response-Time", `${duration.toFixed(2)}ms`);
  response.headers.set("X-Frame-Options", "DENY");
  
  return response;
}

// routes/admin/_middleware.ts - Protected routes
export async function handler(
  req: Request,
  ctx: FreshContext<State>,
) {
  if (!ctx.state.user) {
    return new Response("", {
      status: 303,
      headers: { Location: "/login" },
    });
  }
  
  return ctx.next();
}
```

## API Routes
```tsx
// routes/api/users.ts
import { Handlers } from "$fresh/server.ts";
import { db } from "../../utils/db.ts";

export const handler: Handlers = {
  async GET(req) {
    const url = new URL(req.url);
    const limit = Number(url.searchParams.get("limit")) || 10;
    const offset = Number(url.searchParams.get("offset")) || 0;
    
    const users = await db.users.findMany({ limit, offset });
    
    return Response.json(users);
  },
  
  async POST(req) {
    const { name, email } = await req.json();
    
    if (!name || !email) {
      return Response.json(
        { error: "Name and email required" },
        { status: 400 }
      );
    }
    
    const user = await db.users.create({ name, email });
    
    return Response.json(user, { status: 201 });
  },
};
```

## Static Components
```tsx
// components/Header.tsx
interface HeaderProps {
  user?: { name: string } | null;
}

export default function Header({ user }: HeaderProps) {
  return (
    <header>
      <nav>
        <a href="/">Home</a>
        <a href="/blog">Blog</a>
        <a href="/about">About</a>
        
        {user ? (
          <span>Welcome, {user.name}</span>
        ) : (
          <a href="/login">Login</a>
        )}
      </nav>
    </header>
  );
}
```

## Deployment
```bash
# Deploy to Deno Deploy
deno task build
deployctl deploy --project=my-app main.ts

# Or use GitHub integration with deno.json
{
  "tasks": {
    "start": "deno run -A --watch=static/,routes/ dev.ts",
    "build": "deno run -A dev.ts build",
    "preview": "deno run -A main.ts"
  }
}
```

## Best Practices
- Keep islands minimal - most content should be static
- Use signals for island state management
- Leverage middleware for auth and logging
- Use Deno KV for simple data persistence
- Deploy to Deno Deploy for global edge performance
- Use Fresh plugins for shared functionality

When to Use This Prompt

This Fresh prompt is ideal for developers working on:

Fresh applications requiring modern best practices and optimal performance
Projects that need production-ready Fresh code with proper error handling
Teams looking to standardize their fresh development workflow
Developers wanting to learn industry-standard Fresh patterns and techniques

By using this prompt, you can save hours of manual coding and ensure best practices are followed from the start. It's particularly valuable for teams looking to maintain consistency across their fresh implementations.

How to Use

Copy the prompt - Click the copy button above to copy the entire prompt to your clipboard
Paste into your AI assistant - Use with Claude, ChatGPT, Cursor, or any AI coding tool
Customize as needed - Adjust the prompt based on your specific requirements
Review the output - Always review generated code for security and correctness

💡 Pro Tip: For best results, provide context about your project structure and any specific constraints or preferences you have.

Best Practices

✓ Always review generated code for security vulnerabilities before deploying
✓ Test the Fresh code in a development environment first
✓ Customize the prompt output to match your project's coding standards
✓ Keep your AI assistant's context window in mind for complex requirements
✓ Version control your prompts alongside your code for reproducibility

Frequently Asked Questions

Can I use this Fresh prompt commercially?

Yes! All prompts on Antigravity AI Directory are free to use for both personal and commercial projects. No attribution required, though it's always appreciated.

Which AI assistants work best with this prompt?

This prompt works excellently with Claude, ChatGPT, Cursor, GitHub Copilot, and other modern AI coding assistants. For best results, use models with large context windows.

How do I customize this prompt for my specific needs?

You can modify the prompt by adding specific requirements, constraints, or preferences. For Fresh projects, consider mentioning your framework version, coding style, and any specific libraries you're using.

Related Prompts

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