Cluster + instance improvements

-Moved the database initialize call out of the instance code into the prestart script so that it is now only called once when you start the explorer even if you are running multiple cpus/threads
-The database connection function now uses the default connection string in the event a connection string is not supplied
-Removed unused reference to lib/explorer.js code from the cluster file

bin/cluster

@@ -2,7 +2,6 @@ var cluster = require('cluster');
 
 if (cluster.isMaster) {
   const isWinOS = process.platform == 'win32';
-  const lib = require('../lib/explorer');
   const instances = (process.argv[2] != null && process.argv[2] != '' && !isNaN(process.argv[2]) && Number.isInteger(parseFloat(process.argv[2])) ? parseInt(process.argv[2]) : require('os').cpus().length);
 
   console.log('Starting cluster with pid: ' + process.pid);

bin/instance

@@ -6,15 +6,7 @@ var app = require('../app');
 
 app.set('port', process.env.PORT || settings.webserver.port);
 
-var dbString = 'mongodb://' + encodeURIComponent(settings.dbsettings.user);
+db.connect(null, function() {
-dbString = dbString + ':' + encodeURIComponent(settings.dbsettings.password);
-dbString = dbString + '@' + settings.dbsettings.address;
-dbString = dbString + ':' + settings.dbsettings.port;
-dbString = dbString + '/' + settings.dbsettings.database;
-
-db.connect(dbString, function() {
-  // initialize the database
-  db.initialize_data_startup(function() {
   var server = app.listen(app.get('port'), '::', function() {
     debug('Express server listening on port ' + server.address().port);
   });
@@ -33,4 +25,3 @@ db.connect(dbString, function() {
     });
   });
 });
-});

lib/database.js

@@ -286,6 +286,13 @@ module.exports = {
   connect: function(database, cb) {
     mongoose.set('strictQuery', true);
 
+    if (database == null)
+      database = 'mongodb://' + encodeURIComponent(settings.dbsettings.user) +
+        ':' + encodeURIComponent(settings.dbsettings.password) +
+        '@' + settings.dbsettings.address +
+        ':' + settings.dbsettings.port +
+        '/' + settings.dbsettings.database;
+
     mongoose.connect(database).then(() => {
       return cb();
     }).catch((err) => {

scripts/prestart.js

@@ -10,7 +10,7 @@ var nodeVersionRevision = '0';
 
 // check if the nodejs version # is blank or a very long string as that would usually indicate a problem
 if (nodeVersion != null && nodeVersion != '' && nodeVersion.length < 16) {
-  // Remove the 'v' from the beginning of the version string
+  // remove the 'v' from the beginning of the version string
   if (nodeVersion.indexOf('v') == 0)
     nodeVersion = nodeVersion.slice(1);
 
@@ -99,6 +99,12 @@ check_arguments_passed(function(pidName, node_env) {
   // compile scss to css
   execSync('node ./scripts/compile_css.js', {stdio : 'inherit'});
 
+  const db = require('../lib/database');
+
+  // connect to the mongo database
+  db.connect(null, function() {
+    // initialize the database
+    db.initialize_data_startup(function() {
       // check if the webserver should be started from here based on the pidName
       switch (pidName) {
         case 'pm2':
@@ -144,3 +150,5 @@ check_arguments_passed(function(pidName, node_env) {
       // finished pre-loading
       process.exit(0);
     });
+  });
+});