cloudflare

What this skill does

# Cloudflare Platform

Build globally distributed applications on Cloudflare's edge network.

## Quick Start

```bash
# Install Wrangler CLI
npm install -g wrangler

# Login
wrangler login

# Create new Worker
wrangler init my-worker

# Deploy
wrangler deploy
```

## Workers

### Basic Worker
```typescript
// src/index.ts
export default {
  async fetch(request: Request, env: Env, ctx: ExecutionContext): Promise<Response> {
    const url = new URL(request.url);
    
    if (url.pathname === '/api/hello') {
      return Response.json({ message: 'Hello from the edge!' });
    }
    
    return new Response('Not Found', { status: 404 });
  },
};
```

### wrangler.toml Configuration
```toml
name = "my-worker"
main = "src/index.ts"
compatibility_date = "2024-01-01"

[vars]
ENVIRONMENT = "production"

# KV Namespace
[[kv_namespaces]]
binding = "MY_KV"
id = "abc123"

# D1 Database
[[d1_databases]]
binding = "DB"
database_name = "my-database"
database_id = "def456"

# R2 Bucket
[[r2_buckets]]
binding = "BUCKET"
bucket_name = "my-bucket"

# AI
[ai]
binding = "AI"

# Durable Objects
[[durable_objects.bindings]]
name = "COUNTER"
class_name = "Counter"

[[migrations]]
tag = "v1"
new_classes = ["Counter"]
```

### Request Routing
```typescript
export default {
  async fetch(request: Request, env: Env): Promise<Response> {
    const url = new URL(request.url);
    const { pathname } = url;
    
    // Router pattern
    const routes: Record<string, () => Promise<Response>> = {
      '/api/users': () => handleUsers(request, env),
      '/api/posts': () => handlePosts(request, env),
    };
    
    const handler = routes[pathname];
    if (handler) {
      return handler();
    }
    
    // Wildcard matching
    if (pathname.startsWith('/api/users/')) {
      const userId = pathname.split('/')[3];
      return handleUser(userId, request, env);
    }
    
    return new Response('Not Found', { status: 404 });
  },
};
```

## KV Storage

```typescript
interface Env {
  MY_KV: KVNamespace;
}

export default {
  async fetch(request: Request, env: Env): Promise<Response> {
    const url = new URL(request.url);
    
    // Set value
    await env.MY_KV.put('key', 'value', {
      expirationTtl: 3600, // 1 hour
      metadata: { created: Date.now() },
    });
    
    // Get value
    const value = await env.MY_KV.get('key');
    
    // Get with metadata
    const { value: data, metadata } = await env.MY_KV.getWithMetadata('key');
    
    // List keys
    const list = await env.MY_KV.list({ prefix: 'user:' });
    
    // Delete
    await env.MY_KV.delete('key');
    
    return Response.json({ value });
  },
};
```

## D1 Database (SQLite)

```typescript
interface Env {
  DB: D1Database;
}

// Create tables (run once via wrangler d1 execute)
// wrangler d1 execute my-database --file=./schema.sql

export default {
  async fetch(request: Request, env: Env): Promise<Response> {
    // Query
    const { results } = await env.DB.prepare(
      'SELECT * FROM users WHERE id = ?'
    ).bind(1).all();
    
    // Insert
    const { meta } = await env.DB.prepare(
      'INSERT INTO users (name, email) VALUES (?, ?)'
    ).bind('Alice', '[email protected]').run();
    
    // Batch operations
    const batch = await env.DB.batch([
      env.DB.prepare('INSERT INTO logs (action) VALUES (?)').bind('login'),
      env.DB.prepare('UPDATE users SET last_login = ? WHERE id = ?').bind(Date.now(), 1),
    ]);
    
    // First result only
    const user = await env.DB.prepare(
      'SELECT * FROM users WHERE email = ?'
    ).bind('[email protected]').first();
    
    return Response.json({ results, insertId: meta.last_row_id });
  },
};
```

### Schema Example
```sql
-- schema.sql
CREATE TABLE IF NOT EXISTS users (
  id INTEGER PRIMARY KEY AUTOINCREMENT,
  name TEXT NOT NULL,
  email TEXT UNIQUE NOT NULL,
  created_at DATETIME DEFAULT CURRENT_TIMESTAMP
);

CREATE TABLE IF NOT EXISTS posts (
  id INTEGER PRIMARY KEY AUTOINCREMENT,
  user_id INTEGER NOT NULL,
  title TEXT NOT NULL,
  content TEXT,
  FOREIGN KEY (user_id) REFERENCES users(id)
);
```

## R2 Object Storage

```typescript
interface Env {
  BUCKET: R2Bucket;
}

export default {
  async fetch(request: Request, env: Env): Promise<Response> {
    const url = new URL(request.url);
    const key = url.pathname.slice(1);
    
    switch (request.method) {
      case 'PUT': {
        // Upload file
        const body = await request.arrayBuffer();
        await env.BUCKET.put(key, body, {
          httpMetadata: {
            contentType: request.headers.get('content-type') || 'application/octet-stream',
          },
          customMetadata: {
            uploadedBy: 'api',
          },
        });
        return new Response('Uploaded', { status: 201 });
      }
      
      case 'GET': {
        // Download file
        const object = await env.BUCKET.get(key);
        if (!object) {
          return new Response('Not Found', { status: 404 });
        }
        
        const headers = new Headers();
        object.writeHttpMetadata(headers);
        headers.set('etag', object.httpEtag);
        
        return new Response(object.body, { headers });
      }
      
      case 'DELETE': {
        await env.BUCKET.delete(key);
        return new Response('Deleted');
      }
      
      default:
        return new Response('Method Not Allowed', { status: 405 });
    }
  },
};

// List objects
async function listObjects(env: Env, prefix?: string) {
  const listed = await env.BUCKET.list({
    prefix,
    limit: 100,
  });
  return listed.objects.map(obj => ({
    key: obj.key,
    size: obj.size,
    uploaded: obj.uploaded,
  }));
}
```

## Cloudflare AI

```typescript
interface Env {
  AI: Ai;
}

export default {
  async fetch(request: Request, env: Env): Promise<Response> {
    const { prompt } = await request.json();
    
    // Text generation (Llama, Mistral, etc.)
    const response = await env.AI.run('@cf/meta/llama-3-8b-instruct', {
      messages: [
        { role: 'system', content: 'You are a helpful assistant.' },
        { role: 'user', content: prompt },
      ],
      max_tokens: 1024,
    });
    
    return Response.json(response);
  },
};

// Image generation
async function generateImage(env: Env, prompt: string) {
  const response = await env.AI.run('@cf/stabilityai/stable-diffusion-xl-base-1.0', {
    prompt,
    num_steps: 20,
  });
  
  return new Response(response, {
    headers: { 'content-type': 'image/png' },
  });
}

// Text embeddings
async function getEmbeddings(env: Env, text: string) {
  const response = await env.AI.run('@cf/baai/bge-base-en-v1.5', {
    text: [text],
  });
  return response.data[0]; // Float32Array
}

// Image classification
async function classifyImage(env: Env, imageData: ArrayBuffer) {
  const response = await env.AI.run('@cf/microsoft/resnet-50', {
    image: [...new Uint8Array(imageData)],
  });
  return response;
}

// Speech to text
async function transcribe(env: Env, audioData: ArrayBuffer) {
  const response = await env.AI.run('@cf/openai/whisper', {
    audio: [...new Uint8Array(audioData)],
  });
  return response.text;
}
```

## Durable Objects

```typescript
// Durable Object class
export class Counter {
  state: DurableObjectState;
  
  constructor(state: DurableObjectState) {
    this.state = state;
  }
  
  async fetch(request: Request): Promise<Response> {
    const url = new URL(request.url);
    
    let value = (await this.state.storage.get<number>('count')) || 0;
    
    switch (url.pathname) {
      case '/increment':
        value++;
        await this.state.storage.put('count', value);
        break;
      case '/decrement':
        value--;
        await this.state.storage.put('count', value);
        break;
    }
    
    return Response.json({ count: value });
  }
}

// Worker using Durable Object
interface Env {
  COUNTER: DurableObjectNamespace;
}

export default {
  async fetch(request: Request, env: Env): Promise<Response> {
    // Get unique ID for