Updated the files.

my-app/node_modules/karma/lib/middleware/proxy.js

@@ -0,0 +1,130 @@
+const url = require('url')
+const { Agent: httpAgent } = require('http')
+const { Agent: httpsAgent } = require('https')
+const httpProxy = require('http-proxy')
+const _ = require('lodash')
+const { lookup } = require('../utils/dns-utils')
+
+const log = require('../logger').create('proxy')
+
+function parseProxyConfig (proxies, config) {
+  proxies = proxies || []
+  return _.sortBy(_.map(proxies, function (proxyConfiguration, proxyPath) {
+    if (typeof proxyConfiguration === 'string') {
+      proxyConfiguration = { target: proxyConfiguration }
+    }
+    let proxyUrl = proxyConfiguration.target
+    // eslint-disable-next-line node/no-deprecated-api
+    const proxyDetails = url.parse(proxyUrl)
+    let pathname = proxyDetails.pathname
+
+    if (proxyPath.endsWith('/') && !proxyUrl.endsWith('/')) {
+      log.warn(`proxy "${proxyUrl}" normalized to "${proxyUrl}/"`)
+      proxyUrl += '/'
+      pathname += '/'
+    }
+
+    if (!proxyPath.endsWith('/') && proxyUrl.endsWith('/')) {
+      log.warn(`proxy "${proxyPath}" normalized to "${proxyPath}/"`)
+      proxyPath += '/'
+    }
+
+    if (pathname === '/' && !proxyUrl.endsWith('/')) {
+      pathname = ''
+    }
+
+    const hostname = proxyDetails.hostname || config.hostname
+    const protocol = proxyDetails.protocol || config.protocol
+    const defaultPorts = {
+      'http:': '80',
+      'https:': '443'
+    }
+    const port = proxyDetails.port || defaultPorts[proxyDetails.protocol] || config.port
+    const changeOrigin = proxyConfiguration.changeOrigin || false
+    const Agent = protocol === 'https:' ? httpsAgent : httpAgent
+    const agent = new Agent({
+      keepAlive: true,
+      lookup
+    })
+    const proxy = httpProxy.createProxyServer({
+      target: { host: hostname, port, protocol },
+      xfwd: true,
+      changeOrigin: changeOrigin,
+      secure: config.proxyValidateSSL,
+      agent
+    })
+
+    ;['proxyReq', 'proxyRes'].forEach(function (name) {
+      const callback = proxyDetails[name] || config[name]
+      if (callback) {
+        proxy.on(name, callback)
+      }
+    })
+
+    proxy.on('error', function proxyError (err, req, res) {
+      if (err.code === 'ECONNRESET' && req.socket.destroyed) {
+        log.debug(`failed to proxy ${req.url} (browser hung up the socket)`)
+      } else {
+        log.warn(`failed to proxy ${req.url} (${err.message})`)
+      }
+
+      res.destroy()
+    })
+
+    return { path: proxyPath, baseUrl: pathname, host: hostname, port, proxy, agent }
+  }), 'path').reverse()
+}
+
+/**
+ * Returns a handler which understands the proxies and its redirects, along with the proxy to use
+ * @param proxies An array of proxy record objects
+ * @param urlRoot The URL root that karma is mounted on
+ * @return {Function} handler function
+ */
+function createProxyHandler (proxies, urlRoot) {
+  if (!proxies.length) {
+    const nullProxy = (request, response, next) => next()
+    nullProxy.upgrade = () => {}
+    return nullProxy
+  }
+
+  function createProxy (request, response, next) {
+    const proxyRecord = proxies.find((p) => request.url.startsWith(p.path))
+    if (proxyRecord) {
+      log.debug(`proxying request - ${request.url} to ${proxyRecord.host}:${proxyRecord.port}`)
+      request.url = request.url.replace(proxyRecord.path, proxyRecord.baseUrl)
+      proxyRecord.proxy.web(request, response)
+    } else {
+      return next()
+    }
+  }
+
+  createProxy.upgrade = function (request, socket, head) {
+    // special-case karma's route to avoid upgrading it
+    if (request.url.startsWith(urlRoot)) {
+      log.debug(`NOT upgrading proxyWebSocketRequest ${request.url}`)
+      return
+    }
+
+    const proxyRecord = proxies.find((p) => request.url.startsWith(p.path))
+    if (proxyRecord) {
+      log.debug(`upgrade proxyWebSocketRequest ${request.url} to ${proxyRecord.host}:${proxyRecord.port}`)
+      request.url = request.url.replace(proxyRecord.path, proxyRecord.baseUrl)
+      proxyRecord.proxy.ws(request, socket, head)
+    }
+  }
+
+  return createProxy
+}
+
+exports.create = function (/* config */config, /* config.proxies */proxies, /* emitter */emitter) {
+  const proxyRecords = parseProxyConfig(proxies, config)
+  emitter.on('exit', (done) => {
+    log.debug('Destroying proxy agents')
+    proxyRecords.forEach((proxyRecord) => {
+      proxyRecord.agent.destroy()
+    })
+    done()
+  })
+  return createProxyHandler(proxyRecords, config.urlRoot)
+}