代碼

/**
 * 示例為請求 https://demo.aliyundoc.com/index.html, 并修改響應頭后返給客戶端
 * 測試時請將 someHost 和 url 替換為您自己的地址
 */
const someHost = "https://demo.aliyundoc.com"
const url = someHost + "/index.html"

addEventListener('fetch', event => {
  event.respondWith(handleRequest(event.request))
})

async function handleRequest(request) {
  const response = await fetch(url)

  // 僅復制返回內容的 body
  const newResponse = new Response(response.body, response)

  // 自定義增加 header
  newResponse.headers.append("custom-ER-add", "ER header")

  // 自定義刪減 header
  newResponse.headers.delete("custom-ER-delete")
  newResponse.headers.delete("custom2-ER-delete")

  // 自定義修改header
  newResponse.headers.set("custom-ER-reset", "ER header")

  return newResponse
}

結果

ER獲取客戶端請求的內容并對header增刪改查后返回給客戶端：