HTTP
The following basic examples demonstrate common use cases for simple HTTP servers.
The following basic examples demonstrate common use cases for simple HTTP servers.
Respond with text
An HTTP server using the std/http module that responds with "Hello World!" string.
CLI Netzo
function handler(_req: Request): Response { return new Response('Hello World!')}Deno.serve(handler)Respond with JSON
An HTTP server using the std/http module that responds to requests with JSON.
CLI Netzo
function handler(_req: Request): Response { const data = { message: 'Hello World!' } const body = JSON.stringify(data, null, 2) return new Response(body, { headers: { 'content-type': 'application/json' }, })}Deno.serve(handler)Using the
Response.json(body) short-hand
Instead of manually building and returing a Response object, the return Response.json(body) short-hand can be used to respond directly with JSON. This will automatically stringify the body and set the content-type header to application/json.function handler(_req: Request): Response { const data = { message: 'Hello World!' } const body = JSON.stringify(data, null, 2) // [!code --] return new Response(body, { // [!code --] headers: { 'content-type': 'application/json' }, // [!code --] }) // [!code --] return Response.json(data) // [!code ++]}Get client IP address
An HTTP server that responds to requests with the client's IP address.
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function handler(req: Request, info: Deno.ServeHandlerInfo): Response { const addr = connInfo.remoteAddr as Deno.NetAddr const ip = addr.hostname return new Response(`Your IP address is <b>${ip}</b>`, { headers: { 'content-type': 'text/html' }, })}Deno.serve(handler)Proxying to other servers
An HTTP server that proxies requests to a different server.
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async function handler(req: Request): Promise<Response> { const url = new URL(req.url) url.protocol = 'https:' url.hostname = 'example.com' url.port = '443' return await fetch(url.href, { headers: req.headers, method: req.method, body: req.body, })}Deno.serve(handler)Wildcard Domain
An HTTP server that serves a wildcard domain.
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function handler(req: Request): Response { const url = new URL(req.url) switch (url.hostname) { case 'en.example.com': return new Response('english') case 'es.example.com': return new Response('español') default: return new Response('default') }}Deno.serve(handler)