app.js

// Copyright 2015-2016, Google, Inc.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
//   http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.

// [START app]
'use strict';

var express = require('express');
var Memcached = require('memcached');

var app = express();

// The environment variables are automatically set by App Engine when running
// on GAE. When running locally, you should have a local instance of the
// memcached daemon running.
var memcachedAddr = process.env.MEMCACHE_PORT_11211_TCP_ADDR || 'localhost';
var memcachedPort = process.env.MEMCACHE_PORT_11211_TCP_PORT || '11211';
var memcached = new Memcached(memcachedAddr + ':' + memcachedPort);

app.get('/', function (req, res, next) {
  memcached.get('foo', function (err, value) {
    if (err) {
      return next(err);
    }
    if (value) {
      return res.status(200).send('Value: ' + value);
    }

    memcached.set('foo', Math.random(), 60, function (err) {
      if (err) {
        return next(err);
      }
      return res.redirect('/');
    });
  });
});

var server = app.listen(process.env.PORT || 8080, function () {
  console.log('App listening on port %s', server.address().port);
  console.log('Press Ctrl+C to quit.');
});
// [END app]