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services/subscriptions.js

@@ -4,24 +4,27 @@ const passport = require('./passport');
 
 module.exports = class Subscriptions {
 
+  // Session data does not automatically attach to websocket req objects.
+  // This middleware code looks for a user in the session and, if it exists,
+  // attaches it to the graph req.
   static deserializeUser(req) {
     return new Promise((resolve, reject) => {
       session(req, {}, () => {
-        
+
         if ('session' in req && 'passport' in req.session && 'user' in req.session.passport) {
           passport.deserializeUser(req.session.passport.user, (err, user) => {
             if (err) {
               return reject(err);
             }
-            
+
             req.user = user;
-            
+
             return resolve(req);
           });
         } else {
           resolve(req);
         }
-        
+
       });
     });
   }