vercel

# Vercel Deployment

Deploy and scale applications on Vercel's edge network.

## Quick Start

```bash
# Install Vercel CLI
npm i -g vercel

# Deploy
vercel

# Production deploy
vercel --prod
```

## vercel.json Configuration

```json
{
  "buildCommand": "npm run build",
  "outputDirectory": ".next",
  "framework": "nextjs",
  "regions": ["iad1", "sfo1"],
  "functions": {
    "api/**/*.ts": {
      "memory": 1024,
      "maxDuration": 30
    }
  },
  "rewrites": [
    { "source": "/api/:path*", "destination": "/api/:path*" },
    { "source": "/:path*", "destination": "/" }
  ],
  "headers": [
    {
      "source": "/api/:path*",
      "headers": [
        { "key": "Access-Control-Allow-Origin", "value": "*" }
      ]
    }
  ],
  "env": {
    "DATABASE_URL": "@database-url"
  }
}
```

## Serverless Functions

```typescript
// api/hello.ts
import type { VercelRequest, VercelResponse } from '@vercel/node';

export default function handler(req: VercelRequest, res: VercelResponse) {
  const { name = 'World' } = req.query;
  res.status(200).json({ message: `Hello ${name}!` });
}
```

## Edge Functions

```typescript
// api/edge.ts
export const config = {
  runtime: 'edge',
};

export default function handler(request: Request) {
  return new Response(JSON.stringify({ message: 'Hello from Edge!' }), {
    headers: { 'content-type': 'application/json' },
  });
}
```

## Next.js App Router

```typescript
// app/api/route.ts
import { NextResponse } from 'next/server';

export async function GET(request: Request) {
  const { searchParams } = new URL(request.url);
  const name = searchParams.get('name') ?? 'World';
  
  return NextResponse.json({ message: `Hello ${name}!` });
}

export async function POST(request: Request) {
  const body = await request.json();
  return NextResponse.json({ received: body });
}
```

## ISR (Incremental Static Regeneration)

```typescript
// app/posts/[id]/page.tsx
export const revalidate = 60; // Revalidate every 60 seconds

export async function generateStaticParams() {
  const posts = await getPosts();
  return posts.map((post) => ({ id: post.id }));
}

export default async function Post({ params }: { params: { id: string } }) {
  const post = await getPost(params.id);
  return <article>{post.content}</article>;
}
```

## Vercel KV (Redis)

```typescript
import { kv } from '@vercel/kv';

// Set
await kv.set('user:123', { name: 'Alice', visits: 0 });

// Get
const user = await kv.get('user:123');

// Increment
await kv.incr('user:123:visits');

// Hash operations
await kv.hset('session:abc', { userId: '123', expires: Date.now() + 3600000 });
const session = await kv.hgetall('session:abc');
```

## Vercel Postgres

```typescript
import { sql } from '@vercel/postgres';

// Query
const { rows } = await sql`SELECT * FROM users WHERE id = ${userId}`;

// Insert
await sql`INSERT INTO users (name, email) VALUES (${name}, ${email})`;

// Transaction
await sql.query('BEGIN');
try {
  await sql`UPDATE accounts SET balance = balance - ${amount} WHERE id = ${from}`;
  await sql`UPDATE accounts SET balance = balance + ${amount} WHERE id = ${to}`;
  await sql.query('COMMIT');
} catch (e) {
  await sql.query('ROLLBACK');
  throw e;
}
```

## Environment Variables

```bash
# Add secret
vercel env add DATABASE_URL production

# Pull env vars locally
vercel env pull .env.local

# List env vars
vercel env ls
```

## Cron Jobs

```json
// vercel.json
{
  "crons": [
    {
      "path": "/api/daily-job",
      "schedule": "0 0 * * *"
    }
  ]
}
```

```typescript
// api/daily-job.ts
export default function handler(req, res) {
  // Verify it's from Vercel Cron
  if (req.headers['authorization'] !== `Bearer ${process.env.CRON_SECRET}`) {
    return res.status(401).end();
  }
  
  // Run job
  await runDailyJob();
  res.status(200).end();
}
```

## Resources

- **Vercel Docs**: https://vercel.com/docs
- **Next.js on Vercel**: https://vercel.com/docs/frameworks/nextjs