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diff --git a/middleware/node_modules/finalhandler/index.js b/middleware/node_modules/finalhandler/index.js
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+++ b/middleware/node_modules/finalhandler/index.js
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+/*!
+ * finalhandler
+ * Copyright(c) 2014-2017 Douglas Christopher Wilson
+ * MIT Licensed
+ */
+
+'use strict'
+
+/**
+ * Module dependencies.
+ * @private
+ */
+
+var debug = require('debug')('finalhandler')
+var encodeUrl = require('encodeurl')
+var escapeHtml = require('escape-html')
+var onFinished = require('on-finished')
+var parseUrl = require('parseurl')
+var statuses = require('statuses')
+var unpipe = require('unpipe')
+
+/**
+ * Module variables.
+ * @private
+ */
+
+var DOUBLE_SPACE_REGEXP = /\x20{2}/g
+var NEWLINE_REGEXP = /\n/g
+
+/* istanbul ignore next */
+var defer = typeof setImmediate === 'function'
+  ? setImmediate
+  : function (fn) { process.nextTick(fn.bind.apply(fn, arguments)) }
+var isFinished = onFinished.isFinished
+
+/**
+ * Create a minimal HTML document.
+ *
+ * @param {string} message
+ * @private
+ */
+
+function createHtmlDocument (message) {
+  var body = escapeHtml(message)
+    .replace(NEWLINE_REGEXP, '<br>')
+    .replace(DOUBLE_SPACE_REGEXP, ' &nbsp;')
+
+  return '<!DOCTYPE html>\n' +
+    '<html lang="en">\n' +
+    '<head>\n' +
+    '<meta charset="utf-8">\n' +
+    '<title>Error</title>\n' +
+    '</head>\n' +
+    '<body>\n' +
+    '<pre>' + body + '</pre>\n' +
+    '</body>\n' +
+    '</html>\n'
+}
+
+/**
+ * Module exports.
+ * @public
+ */
+
+module.exports = finalhandler
+
+/**
+ * Create a function to handle the final response.
+ *
+ * @param {Request} req
+ * @param {Response} res
+ * @param {Object} [options]
+ * @return {Function}
+ * @public
+ */
+
+function finalhandler (req, res, options) {
+  var opts = options || {}
+
+  // get environment
+  var env = opts.env || process.env.NODE_ENV || 'development'
+
+  // get error callback
+  var onerror = opts.onerror
+
+  return function (err) {
+    var headers
+    var msg
+    var status
+
+    // ignore 404 on in-flight response
+    if (!err && headersSent(res)) {
+      debug('cannot 404 after headers sent')
+      return
+    }
+
+    // unhandled error
+    if (err) {
+      // respect status code from error
+      status = getErrorStatusCode(err)
+
+      if (status === undefined) {
+        // fallback to status code on response
+        status = getResponseStatusCode(res)
+      } else {
+        // respect headers from error
+        headers = getErrorHeaders(err)
+      }
+
+      // get error message
+      msg = getErrorMessage(err, status, env)
+    } else {
+      // not found
+      status = 404
+      msg = 'Cannot ' + req.method + ' ' + encodeUrl(getResourceName(req))
+    }
+
+    debug('default %s', status)
+
+    // schedule onerror callback
+    if (err && onerror) {
+      defer(onerror, err, req, res)
+    }
+
+    // cannot actually respond
+    if (headersSent(res)) {
+      debug('cannot %d after headers sent', status)
+      req.socket.destroy()
+      return
+    }
+
+    // send response
+    send(req, res, status, headers, msg)
+  }
+}
+
+/**
+ * Get headers from Error object.
+ *
+ * @param {Error} err
+ * @return {object}
+ * @private
+ */
+
+function getErrorHeaders (err) {
+  if (!err.headers || typeof err.headers !== 'object') {
+    return undefined
+  }
+
+  var headers = Object.create(null)
+  var keys = Object.keys(err.headers)
+
+  for (var i = 0; i < keys.length; i++) {
+    var key = keys[i]
+    headers[key] = err.headers[key]
+  }
+
+  return headers
+}
+
+/**
+ * Get message from Error object, fallback to status message.
+ *
+ * @param {Error} err
+ * @param {number} status
+ * @param {string} env
+ * @return {string}
+ * @private
+ */
+
+function getErrorMessage (err, status, env) {
+  var msg
+
+  if (env !== 'production') {
+    // use err.stack, which typically includes err.message
+    msg = err.stack
+
+    // fallback to err.toString() when possible
+    if (!msg && typeof err.toString === 'function') {
+      msg = err.toString()
+    }
+  }
+
+  return msg || statuses[status]
+}
+
+/**
+ * Get status code from Error object.
+ *
+ * @param {Error} err
+ * @return {number}
+ * @private
+ */
+
+function getErrorStatusCode (err) {
+  // check err.status
+  if (typeof err.status === 'number' && err.status >= 400 && err.status < 600) {
+    return err.status
+  }
+
+  // check err.statusCode
+  if (typeof err.statusCode === 'number' && err.statusCode >= 400 && err.statusCode < 600) {
+    return err.statusCode
+  }
+
+  return undefined
+}
+
+/**
+ * Get resource name for the request.
+ *
+ * This is typically just the original pathname of the request
+ * but will fallback to "resource" is that cannot be determined.
+ *
+ * @param {IncomingMessage} req
+ * @return {string}
+ * @private
+ */
+
+function getResourceName (req) {
+  try {
+    return parseUrl.original(req).pathname
+  } catch (e) {
+    return 'resource'
+  }
+}
+
+/**
+ * Get status code from response.
+ *
+ * @param {OutgoingMessage} res
+ * @return {number}
+ * @private
+ */
+
+function getResponseStatusCode (res) {
+  var status = res.statusCode
+
+  // default status code to 500 if outside valid range
+  if (typeof status !== 'number' || status < 400 || status > 599) {
+    status = 500
+  }
+
+  return status
+}
+
+/**
+ * Determine if the response headers have been sent.
+ *
+ * @param {object} res
+ * @returns {boolean}
+ * @private
+ */
+
+function headersSent (res) {
+  return typeof res.headersSent !== 'boolean'
+    ? Boolean(res._header)
+    : res.headersSent
+}
+
+/**
+ * Send response.
+ *
+ * @param {IncomingMessage} req
+ * @param {OutgoingMessage} res
+ * @param {number} status
+ * @param {object} headers
+ * @param {string} message
+ * @private
+ */
+
+function send (req, res, status, headers, message) {
+  function write () {
+    // response body
+    var body = createHtmlDocument(message)
+
+    // response status
+    res.statusCode = status
+    res.statusMessage = statuses[status]
+
+    // response headers
+    setHeaders(res, headers)
+
+    // security headers
+    res.setHeader('Content-Security-Policy', "default-src 'none'")
+    res.setHeader('X-Content-Type-Options', 'nosniff')
+
+    // standard headers
+    res.setHeader('Content-Type', 'text/html; charset=utf-8')
+    res.setHeader('Content-Length', Buffer.byteLength(body, 'utf8'))
+
+    if (req.method === 'HEAD') {
+      res.end()
+      return
+    }
+
+    res.end(body, 'utf8')
+  }
+
+  if (isFinished(req)) {
+    write()
+    return
+  }
+
+  // unpipe everything from the request
+  unpipe(req)
+
+  // flush the request
+  onFinished(req, write)
+  req.resume()
+}
+
+/**
+ * Set response headers from an object.
+ *
+ * @param {OutgoingMessage} res
+ * @param {object} headers
+ * @private
+ */
+
+function setHeaders (res, headers) {
+  if (!headers) {
+    return
+  }
+
+  var keys = Object.keys(headers)
+  for (var i = 0; i < keys.length; i++) {
+    var key = keys[i]
+    res.setHeader(key, headers[key])
+  }
+}