Cloudflare Workers reverse proxy by Angrymouse

cf-workers-reverse-proxy.js

const corsHeaders = {
  "Access-Control-Allow-Origin": "*",
  "Access-Control-Allow-Methods": "GET,HEAD,POST,OPTIONS",
  "Access-Control-Max-Age": "86400",
}

const API_URL = "https://dev.server-discord.com"//

const PROXY_ENDPOINT = ""

async function JSONResponse(json) {
  return new Response(JSON.stringify(json), {
    headers: {
      "content-type": "application/json;charset=UTF-8",
    },
  })
}

const DEFAULT_RESPONSE={ok:false,errors:["Invalid request to api"]}

async function handleRequest(realRequest) {
  const url = new URL(realRequest.url)
  let apiUrl = API_URL

  // Rewrite request to point to API url. This also makes the request mutable
  // so we can add the correct Origin header to make the API server think
  // that this request isn't cross-site.
  request = new Request(apiUrl+url.pathname.slice(PROXY_ENDPOINT.length), realRequest)
  request.headers.set("Origin", new URL(apiUrl).origin)
    request.headers.set('Authorization', 'Basic ' + btoa("pony:bebetter"));
  
  let response = await fetch(request)

  // Recreate the response so we can modify the headers
  response = new Response(response.body, response)


  // Set CORS headers
  response.headers.set("Access-Control-Allow-Origin", url.origin)

  // Append to/Add Vary header so browser will cache response correctly
  response.headers.append("Vary", "Origin")

  return response
}

function handleOptions(request) {

  let headers = request.headers;
  if (
    headers.get("Origin") !== null &&
    headers.get("Access-Control-Request-Method") !== null &&
    headers.get("Access-Control-Request-Headers") !== null
  ){

    let respHeaders = {
      ...corsHeaders,

      "Access-Control-Allow-Headers": request.headers.get("Access-Control-Request-Headers"),
    }

    return new Response(null, {
      headers: respHeaders,
    })
  }
  else {
    return new Response(null, {
      headers: {
        Allow: "GET, HEAD, POST, OPTIONS",
      },
    })
  }
}

addEventListener("fetch",async function fetchFromDiscordAPI( event) {
  const request = event.request
  const url = new URL(request.url)
  if(url.pathname.startsWith(PROXY_ENDPOINT)){
    if (request.method === "OPTIONS") {
     
      event.respondWith(handleOptions(request))
    }
    else if(
      request.method === "GET" ||
      request.method === "HEAD" ||
      request.method === "POST"
    ){

      event.respondWith(handleRequest(request))
    }
    else {
      event.respondWith(
        new Response(null, {
          status: 405,
          statusText: "Method Not Allowed",
        }),
      )
    }
  }
  else {
    event.respondWith(JSONResponse(DEFAULT_RESPONSE))
  }
})
function sleep(ms){
  return new Promise(resolve=>setTimeout(resolve,ms))
}