only use the redis session backend when the correct environment variable is set. This means that we enable this feature only on specific deploys like k8s and ECS

Author: nustiueudinastea

config.js

@@ -1,12 +1,23 @@
 (function (){
   'use strict';
 
+  var session      = require("express-session"),
+      RedisStore   = require('connect-redis')(session)
+
   module.exports = {
     session: {
       name: 'md.sid',
       secret: 'sooper secret',
       resave: false,
       saveUninitialized: true
+    },
+
+    session_redis: {
+      store: new RedisStore({host: "session-db"}),
+      name: 'md.sid',
+      secret: 'sooper secret',
+      resave: false,
+      saveUninitialized: true
     }
   };
 }());

server.js

@@ -13,19 +13,20 @@ var request      = require("request")
   , catalogue    = require("./api/catalogue")
   , orders       = require("./api/orders")
   , user         = require("./api/user")
-  , RedisStore   = require('connect-redis')(session)
   , app          = express()
 
 epimetheus.instrument(app);
 
 app.use(express.static("public"));
-app.use(session({
-      store: new RedisStore({host: "session-db"}),
-      name: 'md.sid',
-      secret: 'sooper secret',
-      resave: false,
-      saveUninitialized: true
-    }));
+if(process.env.SESSION_REDIS) {
+    console.log('Using the redis based session manager');
+    app.use(session(config.session_redis));
+}
+else {
+    console.log('Using local session manager');
+    app.use(session(config.session_redis));
+}
+
 app.use(bodyParser.json());
 app.use(cookieParser());
 app.use(helpers.errorHandler);