Cloudflare Workers Documentation

Cloudflare Workers provides a serverless execution environment that allows you to create entirely new applications or augment existing ones without configuring or maintaining infrastructure.

Quick Start

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Ready-to-use code to get you started.

Hello World

Simple Hello World in JS

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Hello World Rust

Simple Hello World in Rust

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Bulk Redirects

Redirects requests to certain URLs based a mapped object to the request’s URL.

Copy into a Worker script:
async function handleRequest(request) { let requestURL = new URL(request.url) let path = requestURL.pathname.split('/redirect')[1] let location = redirectMap.get(path) if (location) { return Response.redirect(location, 301) } // If in map, return the original request return fetch(request) } addEventListener('fetch', async event => { event.respondWith(handleRequest(event.request)) }) const externalHostname = '' const redirectMap = new Map([ ['/bulk1', 'https://' + externalHostname + '/redirect2'], ['/bulk2', 'https://' + externalHostname + '/redirect3'], ['/bulk3', 'https://' + externalHostname + '/redirect4'], ['/bulk4', ''], ])

Send Raw HTML

Delivers an HTML page from HTML directly in the Worker script.

Copy into a Worker script:
async function handleRequest(request) { const init = { headers: { 'content-type': 'text/html;charset=UTF-8', }, } return new Response(someHTML, init) } addEventListener('fetch', event => { return event.respondWith(handleRequest(event.request)) }) const someHTML = `<!DOCTYPE html> <html> <body> <h1>Hello World</h1> <p>This is all generated using a Worker</p> <iframe width="560" height="315" src="" frameborder="0" allow="accelerometer; autoplay; encrypted-media; gyroscope; picture-in-picture" allowfullscreen ></iframe> </body> </html> `
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