parse ios udid in safari from mobileconfig file using express as a middleware

iOS-UDID-Safari-Parser.js

const parseString = require('xml2js').parseString
const _ = require('lodash')

/**
 * 通过 safari 浏览器获取 iOS 的 udid
 * POST 过来的是二进制，不是标准的 xml
 * https://www.exchen.net/%E9%80%9A%E8%BF%87-safari-%E6%B5%8F%E8%A7%88%E5%99%A8%E8%8E%B7%E5%8F%96-udid.html
 */
function parser (req, res, next) {
  if (req.method !== 'POST' || req.get('content-type') !== 'application/pkcs7-signature') {
    next()
    return
  }

  const tag = 'dict'
  let data = ''
  req.setEncoding('utf8')
  req.on('data', function (chunk) {
    data += chunk
  })
  req.on('end', function () {
    let xmlStr = data.slice(data.indexOf(`<${tag}>`), data.indexOf(`</${tag}>`)) + `</${tag}>`
    parseString(xmlStr, function (err, result) {
      if (err) {
        next(err)
      } else {
        req.body = _.zipObject(result[tag].key, result[tag].string)
        next()
      }
    })
  })
}

module.exports = parser

/*
<dict>
<key>IMEI</key>
<string>35 382108 864314 5</string>
<key>PRODUCT</key>
<string>iPhone9,2</string>
<key>UDID</key>
<string>9636243e9bb07fe57b27ab252b424a1cfc9d0595</string>
<key>VERSION</key>
<string>16E227</string>
</dict>
*/