Better error handling, use better practices.

.editorconfig

@@ -0,0 +1,13 @@
+# Tells the .editorconfg plugin to stop searching once it finds this file
+root = true
+
+[*]
+indent_size = 2
+indent_style = space
+charset = utf-8
+end_of_line = lf
+insert_final_newline = true
+trim_trailing_whitespace = true
+
+[*.md]
+trim_trailing_whitespace = false

package.json

@@ -4,18 +4,18 @@
   "description": "Node.js sample app for OpenShift 3",
   "main": "server.js",
   "dependencies": {
-    "chai": "^3.5.0",
-    "chai-http": "^2.0.1",
     "ejs": "^2.4.1",
     "express": "^4.13.4",
-    "mocha": "^2.4.5",
     "mongodb": "^2.1.16",
-    "morgan": "^1.7.0",
-    "object-assign":"4.1.0"
+    "morgan": "^1.7.0"
+  },
+  "devDependencies": {
+    "chai": "^3.5.0",
+    "chai-http": "^2.0.1",
+    "mocha": "^2.4.5"
   },
   "engine": {
-    "node": "*",
-    "npm": "*"
+    "node": ">=4"
   },
   "scripts": {
     "start": "node server.js",

server.js

@@ -1,105 +1,97 @@
+'use strict';
+
 //  OpenShift sample Node application
-var express = require('express'),
-    app     = express(),
-    morgan  = require('morgan');
-
-Object.assign=require('object-assign')
+const express = require('express'),
+  app = express(),
+  morgan = require('morgan'),
+  MongoClient = require('mongodb').MongoClient;
 
 app.engine('html', require('ejs').renderFile);
-app.use(morgan('combined'))
-
-var port = process.env.PORT || process.env.OPENSHIFT_NODEJS_PORT || 8080,
-    ip   = process.env.IP   || process.env.OPENSHIFT_NODEJS_IP || '0.0.0.0',
-    mongoURL = process.env.OPENSHIFT_MONGODB_DB_URL || process.env.MONGO_URL,
-    mongoURLLabel = "";
-
-if (mongoURL == null && process.env.DATABASE_SERVICE_NAME) {
-  var mongoServiceName = process.env.DATABASE_SERVICE_NAME.toUpperCase(),
-      mongoHost = process.env[mongoServiceName + '_SERVICE_HOST'],
-      mongoPort = process.env[mongoServiceName + '_SERVICE_PORT'],
-      mongoDatabase = process.env[mongoServiceName + '_DATABASE'],
-      mongoPassword = process.env[mongoServiceName + '_PASSWORD']
-      mongoUser = process.env[mongoServiceName + '_USER'];
-
-  if (mongoHost && mongoPort && mongoDatabase) {
-    mongoURLLabel = mongoURL = 'mongodb://';
-    if (mongoUser && mongoPassword) {
-      mongoURL += mongoUser + ':' + mongoPassword + '@';
-    }
-    // Provide UI label that excludes user id and pw
-    mongoURLLabel += mongoHost + ':' + mongoPort + '/' + mongoDatabase;
-    mongoURL += mongoHost + ':' +  mongoPort + '/' + mongoDatabase;
-
-  }
-}
-var db = null,
-    dbDetails = new Object();
-
-var initDb = function(callback) {
-  if (mongoURL == null) return;
-
-  var mongodb = require('mongodb');
-  if (mongodb == null) return;
-
-  mongodb.connect(mongoURL, function(err, conn) {
-    if (err) {
-      callback(err);
-      return;
-    }
-
-    db = conn;
-    dbDetails.databaseName = db.databaseName;
-    dbDetails.url = mongoURLLabel;
-    dbDetails.type = 'MongoDB';
-
-    console.log('Connected to MongoDB at: %s', mongoURL);
-  });
-};
-
-app.get('/', function (req, res) {
-  // try to initialize the db on every request if it's not already
-  // initialized.
-  if (!db) {
-    initDb(function(err){});
-  }
-  if (db) {
-    var col = db.collection('counts');
-    // Create a document with request IP and current time of request
-    col.insert({ip: req.ip, date: Date.now()});
-    col.count(function(err, count){
-      res.render('index.html', { pageCountMessage : count, dbInfo: dbDetails });
-    });
-  } else {
-    res.render('index.html', { pageCountMessage : null});
-  }
+app.use(morgan('combined'));
+
+const port = process.env.PORT || process.env.OPENSHIFT_NODEJS_PORT || 8080,
+  ip = process.env.IP || process.env.OPENSHIFT_NODEJS_IP || '0.0.0.0',
+  mongoInfo = getMongoInfo();
+
+const dbPromise = MongoClient.connect(mongoInfo.url);
+
+app.get('/', function (req, res, next) {
+  return dbPromise.then((db) => {
+    const countsCol = db.collection('counts');
+
+    return countsCol.insert({ ip: req.ip, date: Date.now() })
+      .then(() => countsCol.count())
+      .then((count) => {
+        res.render('index.html', {
+          pageCountMessage: count,
+          dbInfo: {
+            databaseName: db.databaseName,
+            url: mongoInfo.label,
+            type: 'MongoDB'
+          }
+        });
+      })
+  })
+  .catch(next);
 });
 
-app.get('/pagecount', function (req, res) {
-  // try to initialize the db on every request if it's not already
-  // initialized.
-  if (!db) {
-    initDb(function(err){});
-  }
-  if (db) {
-    db.collection('counts').count(function(err, count ){
-      res.send('{ pageCount: ' + count + '}');
-    });
-  } else {
-    res.send('{ pageCount: -1 }');
-  }
+app.get('/pagecount', function (req, res, next) {
+  return dbPromise.then((db) => db.collection('counts').count())
+    .then((count) => res.json({
+      pageCount: count
+    }))
+    .catch(next);
 });
 
 // error handling
-app.use(function(err, req, res, next){
-  console.error(err.stack);
+app.use(function (err, req, res, next) {
+  console.error(err.stack || err);
   res.status(500).send('Something bad happened!');
 });
 
-initDb(function(err){
-  console.log('Error connecting to Mongo. Message:\n'+err);
+app.listen(port, ip, () => console.log('Server running on http://%s:%s', ip, port));
+
+// In case there was an error initializing the database
+dbPromise.catch((err) => {
+  console.error('Error initializing database:', err.stack || err);
+  process.exit(-1);
 });
 
-app.listen(port, ip);
-console.log('Server running on http://%s:%s', ip, port);
 
-module.exports = app ;
+
+function getMongoInfo() {
+  const mongoURL = process.env.OPENSHIFT_MONGODB_DB_URL || process.env.MONGO_URL;
+  if (mongoURL) {
+    return {
+      url: mongoURL,
+      label: ''
+    };
+  }
+
+  const serviceName = process.env.DATABASE_SERVICE_NAME;
+  if (!serviceName) {
+    throw new Error('One of OPENSHIFT_MONGODB_DB_URL|MONGO_URL|DATABASE_SERVICE_NAME env variables must be defined');
+  }
+
+  const mongoHost = process.env[mongoServiceName + '_SERVICE_HOST'],
+    mongoPort = process.env[mongoServiceName + '_SERVICE_PORT'],
+    mongoDatabase = process.env[mongoServiceName + '_DATABASE'],
+    mongoPassword = process.env[mongoServiceName + '_PASSWORD']
+  mongoUser = process.env[mongoServiceName + '_USER'];
+
+  if (!mongoHost || !mongoPort || !mongoDatabase) {
+    throw new Error('When using DATABASE_SERVICE_NAME, you must also provide _SERVICE_HOST, _SERVICE_PORT, and _DATABASE env variables');
+  }
+
+  let mongoAuth = '';
+  if (mongoUser && mongoPassword) {
+    mongoAuth = mongoUser + ':' + mongoPassword + '@';
+  }
+
+  const url = mongoHost + ':' + mongoPort + '/' + mongoDatabase;
+  return {
+    url: 'mongodb://' + mongoAuth + url,
+    label: 'mongodb://' + url
+  };
+
+}

tests/app_test.js

@@ -1,31 +1,36 @@
-var server   = require('../server'),
-    chai     = require('chai'),
-    chaiHTTP = require('chai-http'),
-    should   = chai.should();
+'use strict';
 
-chai.use(chaiHTTP);
-
-reqServer = process.env.HTTP_TEST_SERVER || server
+const server = require('../server'),
+  chai = require('chai'),
+  chaiHTTP = require('chai-http'),
+  should = chai.should();
 
-describe('Basic routes tests', function() {
-
-    it('GET to / should return 200', function(done){
-        chai.request(reqServer)
-        .get('/')
-        .end(function(err, res) {
-            res.should.have.status(200);
-            done();
-        })
+chai.use(chaiHTTP);
 
-    })
+const reqServer = process.env.HTTP_TEST_SERVER || server;
 
-    it('GET to /pagecount should return 200', function(done){
-        chai.request(reqServer)
-        .get('/pagecount')
-        .end(function(err, res) {
-            res.should.have.status(200);
-            done();
-        })
+describe('Basic routes tests', function () {
+  it('GET to / should return 200', function (done) {
+    chai.request(reqServer)
+      .get('/')
+      .end(function (err, res) {
+        if (err) {
+          return done(err);
+        }
+        res.should.have.status(200);
+        done();
+      });
+  });
 
-    })
-})
+  it('GET to /pagecount should return 200', function (done) {
+    chai.request(reqServer)
+      .get('/pagecount')
+      .end(function (err, res) {
+        if (err) {
+          return done(err);
+        }
+        res.should.have.status(200);
+        done();
+      });
+  });
+});