用Cloudflare Worker加速Github文件访问

2021-10-25

字数统计:363字阅读时长≈1分

之前一直用jsDelivr来加速Github项目中的一些文件访问，最近发现用jsDelivr无法访问项目里的apk文件了，遂将目光转向Worker

在Cloudflare 里创建 Worker添加下面代码，测试ok后解析到域名就能用

目前满足使用需求，避免滥用写死了我自己的仓库

访问文件时，可选参数c是仓库，m是分支
https://res.gddhy.net/app/release/app-release.apk?c=coolapk-emotion

const url = "https://raw.githubusercontent.com/gddhy/"

addEventListener("fetch", event => {
  const str = event.request.url
  var link = ""
  var master = "master"
  var cangku = "blog-res"
  const inText = ".gddhy.net/"
  if(str.indexOf(inText)>=0 ){
    link = str.substring(str.indexOf(inText)+inText.length)
    if(link.indexOf("?")>=0){
      link = link.substring(0,link.indexOf("?"))
    }
  } 

  if(str.indexOf("?")>=0){
    var data = str.substring(str.indexOf("?")+1)
    cangku = getQueryVariable(data,"c",cangku)
    master = getQueryVariable(data,"m",master)
  }

  link = url + cangku + "/" + master + "/" + link

  return event.respondWith(handleRequest(link))
})

async function gatherResponse(response) {
  const { headers } = response
  const contentType = headers.get("content-type") || ""
  if (contentType.includes("application/json")) {
    return JSON.stringify(await response.json())
  }
  else if (contentType.includes("application/text")) {
    return response.text()
  }
  else if (contentType.includes("text/html")) {
    return response.text()
  }
  else {
    return response.blob()
  }
}

async function handleRequest(link) {
  var lastChar = link.substring(link.length - 1)
  if(lastChar.indexOf("/")>=0){
    return new Response("ERROR", { status: 200 })
  }

  const init = {
    headers: {
      "content-type": "application/octet-stream",
    },
  }
  
  const response = await fetch(link, init)
  const results = await gatherResponse(response)
  return new Response(results, init)
}

function getQueryVariable(data,variable,defaultData) {
  var vars = data.split("&");
    for (var i=0;i<vars.length;i++) {
      var pair = vars[i].split("=")
      if(pair[0] == variable){
        return pair[1];
      }
  }
  return defaultData;
}