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Data loss prevention

Protect sensitive data to prevent data loss, and send alerts to a webhooks server in the event of a data breach.

const DEBUG = trueconst SOME_HOOK_SERVER = "https://webhook.flow-wolf.io/hook"/** * Alert a data breach by posting to a webhook server */async function postDataBreach(request) {  const trueClientIp = request.headers.get("cf-connecting-ip")  const epoch = new Date().getTime()  const body = {    ip: trueClientIp,    time: epoch,    request: request  }  const init = {    body: JSON.stringify(body),    method: "POST",    headers: {      "content-type": "application/json;charset=UTF-8"    },  }  return await fetch(SOME_HOOK_SERVER, init)}/** * Define personal data with regular expressions. * Respond with block if credit card data, and strip * emails and phone numbers from the response. * Execution will be limited to MIME type "text/*". */async function handleRequest(request) {  const response = await fetch(request)
  // Return origin response, if response wasn’t text  const contentType = response.headers.get("content-type") || ""  if (!contentType.toLowerCase().includes("text/")) {    return response  }
  let text = await response.text()
  // When debugging replace the response  // from the origin with an email  text = DEBUG    ? text.replace("You may use this", "me@example.com may use this")    : text
  const sensitiveRegexsMap = {    creditCard: String.raw`\b(?:4[0-9]{12}(?:[0-9]{3})?|(?:5[1-5][0-9]{2}|222[1-9]|22[3-9][0-9]|2[3-6][0-9]{2}|27[01][0-9]|2720)[0-9]{12}|3[47][0-9]{13}|3(?:0[0-5]|[68][0-9])[0-9]{11}|6(?:011|5[0-9]{2})[0-9]{12}|(?:2131|1800|35\d{3})\d{11})\b`,    email: String.raw`\b[A-Z0-9._%+-]+@[A-Z0-9.-]+\.[A-Z]{2,}\b`,    phone: String.raw`\b07\d{9}\b`  }
  for (const kind in sensitiveRegexsMap) {    const sensitiveRegex = new RegExp(sensitiveRegexsMap[kind], "ig")    const match = await sensitiveRegex.test(text)    if (match) {      // Alert a data breach      await postDataBreach(request)
      // Respond with a block if credit card,      // otherwise replace sensitive text with `*`s      return kind === "creditCard"        ? new Response(kind + " found\nForbidden\n", {            status: 403,            statusText: "Forbidden"          })        : new Response(text.replace(sensitiveRegex, "**********"), response)    }  }  return new Response(text, response)}
addEventListener("fetch", event => {  event.respondWith(handleRequest(event.request))})