cloudflare

Cloudflare Skill

You are working with Cloudflare Workers / Pages. Apply these conventions.

Workers

• Workers run in the V8 isolate environment — no Node.js built-ins by default; use the compatibility flag nodejs_compat for Node.js API support.
• Export a default object with a fetch handler:

  export default {
    async fetch(request: Request, env: Env, ctx: ExecutionContext): Promise<Response> {
      return new Response('Hello');
    },
  };
  

• Define the Env interface from wrangler.toml bindings — never use process.env in Workers.

wrangler.toml

• Define KV namespaces, R2 buckets, D1 databases, and Durable Objects as bindings in wrangler.toml.
• Use [vars] for non-secret env vars; use wrangler secret put for secrets.
• Use compatibility_date to pin the runtime behavior; update periodically.

Cloudflare KV

• KV is eventually consistent and best for read-heavy, infrequently written data.
• Use env.KV.put(key, value, { expirationTtl: 3600 }) for TTL-based expiry.
• Use env.KV.getWithMetadata(key) to retrieve value and metadata in one call.

Cloudflare D1 (SQLite)

• Run migrations with wrangler d1 migrations apply DB_NAME.
• Use the D1 client: await env.DB.prepare('SELECT * FROM users WHERE id = ?').bind(id).first().
• Use .all() for multiple rows, .first() for a single row, .run() for mutations (INSERT/UPDATE/DELETE).

Cloudflare R2

• R2 is S3-compatible object storage with no egress fees.
• Upload: await env.BUCKET.put(key, body, { httpMetadata: { contentType: 'image/png' } }).
• Generate pre-signed URLs with createPresignedUrl() from the S3-compatible API.

Pages

• Cloudflare Pages Functions live in functions/ — they map to URL routes.
• Use export const onRequestGet: PagesFunction<Env> = async (ctx) => { … }.
• Share Env types between Workers and Pages Functions via a shared bindings.d.ts.

Security

• Always validate cf-connecting-ip / CF-Ray headers carefully — they can be spoofed if Workers are called directly.
• Use Cloudflare Access for protecting internal routes instead of custom auth.