automatic token refresh, initial stage

backend/helpers/database.js

@@ -0,0 +1,21 @@
+const config = require('../config');
+
+var db = null;
+
+
+module.exports = {
+    initModule : function(databaseObject){
+        db=databaseObject;
+    },
+
+    loadTokens : function(){
+        db.collection('token_list').findOne().then(tokens=>{
+            config.TOKEN = tokens.access_token;
+            config.REFRESH_TOKEN = tokens.refresh_token;
+            config.TOKEN_EXPIRES_IN = tokens.expires_in;
+            console.log("Tokens loaded");
+        }).catch(e=>{
+            console.log("Error loading tokens");
+        })
+    }
+}