From 9c3bcb88aba3cc67f2f624f53214d6788f8a412f Mon Sep 17 00:00:00 2001
From: rohantarai <16543074+rohantarai@users.noreply.github.com>
Date: Wed, 27 Nov 2019 11:38:46 +0530
Subject: [PATCH] updated to support mongodb v3.2 and above

---
 lib/databases/mongodb.js | 44 ++++++++++++++++++++++++----------------
 1 file changed, 26 insertions(+), 18 deletions(-)

diff --git a/lib/databases/mongodb.js b/lib/databases/mongodb.js
index b46054a..25683b0 100644
--- a/lib/databases/mongodb.js
+++ b/lib/databases/mongodb.js
@@ -6,7 +6,7 @@ var util = require('util'),
     isNew = mongoVersion.indexOf('1.') !== 0,
     ObjectID = isNew ? mongo.ObjectID : mongo.BSONPure.ObjectID,
     _ = require('lodash');
-
+  
 function cleanSessionData(json) {
   if (!json) {
     return json;
@@ -41,18 +41,21 @@ var MongoSessionStore = function (options) {
   _.defaults(options, defaults);
 
   var defaultOpt = {
-    ssl: false
+    // ssl is by default false in node-mongodb-native driver v1.4.x / v2.2 and above
+    // ssl: false
   };
 
   options.options = options.options || {};
 
   if (isNew) {
-    defaultOpt.autoReconnect = false;
+    // autoReconnect needs to be true to reconnect on failure, by default it is true in node-mongodb-native driver v2.2 and above
+    // defaultOpt.autoReconnect = false;
     defaultOpt.useNewUrlParser = true;
     defaultOpt.useUnifiedTopology = true;
     _.defaults(options.options, defaultOpt);
   } else {
-    defaultOpt.auto_reconnect = false;
+    // auto_reconnect not required as by default it is false in node-mongodb-native driver v1.4.x
+    // defaultOpt.auto_reconnect = false;
     _.defaults(options.options, defaultOpt);
   }
 
@@ -69,15 +72,19 @@ _.extend(MongoSessionStore.prototype, {
     var options = this.options;
 
     var connectionUrl;
+    var client;
 
+    // for mongodb Atlas uri / local mongodb v3.2 and above replicset uri
     if (options.url) {
       connectionUrl = options.url;
-    } else {
+    }
+    // for local mongodb v3.2 and above (not replicaset)
+    else {
       var members = options.servers
         ? options.servers
-        : [{host: options.host, port: options.port}];
+        : [{ host: options.host, port: options.port }];
 
-      var memberString = _(members).map(function(m) { return m.host + ':' + m.port; });
+      var memberString = _(members).map(function (m) { return m.host + ':' + m.port; });
       var authString = options.username && options.password
         ? options.username + ':' + options.password + '@'
         : '';
@@ -88,11 +95,10 @@ _.extend(MongoSessionStore.prototype, {
       connectionUrl = 'mongodb://' + authString + memberString + '/' + options.dbName + optionsString;
     }
 
-    var client;
-
+    // for node-mongodb-native driver v2.2 and above
     if (mongo.MongoClient.length === 2) {
       client = new mongo.MongoClient(connectionUrl, options.options);
-      client.connect(function(err, cl) {
+      client.connect(function (err, cl) {
         if (err) {
           if (callback) callback(err);
           return;
@@ -104,9 +110,11 @@ _.extend(MongoSessionStore.prototype, {
         }
         initDb();
       });
-    } else {
+    }
+    // for node-mongodb-native driver v1.4.x
+    else {
       client = new mongo.MongoClient();
-      client.connect(connectionUrl, options.options, function(err, db) {
+      client.connect(connectionUrl, options.options, function (err, db) {
         if (err) {
           if (callback) callback(err);
           return;
@@ -126,7 +134,7 @@ _.extend(MongoSessionStore.prototype, {
 
       var finish = function (err) {
         self.sessions = self.db.collection(options.collectionName);
-        self.sessions.ensureIndex({ expires: 1 }, { expireAfterSeconds: 0 }, function() {});
+        self.sessions.createIndex({ expires: 1 }, { expireAfterSeconds: 0 }, function() {});
         if (!err) {
           self.isConnected = true;
           self.emit('connect');
@@ -210,7 +218,7 @@ _.extend(MongoSessionStore.prototype, {
 
     if (!this.options.ignoreConcurrency) sess._hash = new ObjectID().toString();
 
-    this.sessions.update(query, sess, { upsert: true, safe: true }, function(err, modifiedCount) {
+    this.sessions.updateOne(query, { $set: sess }, { upsert: true }, function(err, modifiedCount) {
       if (err && err.message && err.message.indexOf('duplicate key') > -1) {
         return callback(new Error('ConcurrencyError: Session was updated by someone else!'));
       }
@@ -247,11 +255,11 @@ _.extend(MongoSessionStore.prototype, {
   },
 
   destroy: function (sid, callback) {
-    this.sessions.remove({ _id: sid }, callback || function () {});
+    this.sessions.deleteOne({ _id: sid }, callback || function () {});
   },
 
   length: function (callback) {
-    this.sessions.count(callback || function () {});
+    this.sessions.estimatedDocumentCount(callback || function() {});
   },
 
   all: function (callback) {
@@ -268,9 +276,9 @@ _.extend(MongoSessionStore.prototype, {
   },
 
   clear: function (callback) {
-    this.sessions.remove(callback || function () {});
+    this.sessions.deleteMany(callback || function() {});
   }
 
 });
 
-module.exports = MongoSessionStore;
+module.exports = MongoSessionStore;
\ No newline at end of file