Add checker in order to start authentication when configured (#9)

In this commit was added the capability of run this server
when the user doesn't configured the facebook oauth service
and this should be acessible without anykind of authentication.

NOTE: This should be used only in dev mode

server.js

@@ -9,11 +9,12 @@ dotenv.config();
 
 const logger = require('./utils/logger');
 const { apiErrorHandler, resourceNotFoundHandler, isAuthenticated } = require('./utils/express-middleware');
+const { hasAuthentication } = require('./utils/common');
 
 const api = require('./api');
-const auth = require('./auth');
 
 const app = express();
+const serverLogger = logger('server');
 
 app.use(session({
     secret: process.env.APP_SESSION_SALT,
@@ -22,7 +23,12 @@ app.use(session({
     saveUninitialized: true
 }));
 
-auth(app);
+if (hasAuthentication()) {
+    const auth = require('./auth');
+
+    serverLogger.info('Server started with authentication configured');
+    auth(app);
+}
 
 // Add some basic security
 app.use(helmet());
@@ -46,4 +52,4 @@ const port = process.env.APP_SERVER_PORT || 3000; // set our port
 // Start the server
 app.listen(port);
 
-logger('server').info(`trackovid-19 server started on port ${port}`);
+serverLogger.info(`trackovid-19 server started on port ${port}`);

utils/common.js

@@ -0,0 +1,13 @@
+function hasFacebookCredentials () {
+    return process.env.FB_APP_ID !== undefined &&
+        process.env.FB_APP_SECRET !== undefined &&
+        process.env.FB_CALLBACK_URL !== undefined;
+}
+
+function hasAuthentication () {
+   return hasFacebookCredentials();
+}
+
+module.exports = {
+    hasAuthentication
+};

utils/express-middleware.js

@@ -1,6 +1,7 @@
 const logger = require('./logger');
 const HTTP_STATUS_CODE = require('../enums/http-status-code');
 const API_ERRORS = require('../enums/api-errors');
+const { hasAuthentication } = require('../utils/common');
 
 /**
  * Handles the unexpected API errors
@@ -50,7 +51,7 @@ function resourceNotFoundHandler (req, res, next) {
  * with the unauthorized status code.
  */
 function isAuthenticated (req, res, next) {
-    if (req.isAuthenticated() || process.env.MOCK_SERVICES === "true") {
+    if (req.isAuthenticated() || !hasAuthentication() || process.env.MOCK_SERVICES === "true") {
         next();
     } else {
         logger('express-middleware-auth').info(