Add support for mongodb v3

.travis.yml

@@ -1,17 +1,18 @@
 language: node_js
 
 node_js:
-  - "6"
-  - "8"
+  - "12"
   - "10"
+  - "8"
 
 services:
   - docker
 
 env:
-  - MONGODB_VERSION="2.6"
-  - MONGODB_VERSION="3.6"
+  - MONGODB_VERSION="4.2"
   - MONGODB_VERSION="4.0"
+  - MONGODB_VERSION="3.6"
+  - MONGODB_VERSION="3.4"
 
 before_install:
   - docker run -d -p 127.0.0.1:27017:27017 mongo:$MONGODB_VERSION

README.md

@@ -25,7 +25,7 @@ const shareDb = new ShareDB({ milestoneDb: milestoneDb });
 
 ### Mongo
 
-The underlying Mongo database can be configured in a number of ways. This library wraps v2 of the [`mongodb`][2]
+The underlying Mongo database can be configured in a number of ways. This library uses the [`mongodb`][2]
 library, so any configuration that can be used there can be used in this library.
 
 Mongo can be configured simply using a connection string and any desired [options][3]:
@@ -34,7 +34,7 @@ Mongo can be configured simply using a connection string and any desired [option
 const milestoneDb = new MongoMilestoneDB('mongodb://localhost:27017/test', { loggerLevel: 'debug' });
 ```
 
-It can also be configured with a callback that provides an instance of a Mongo [`Db` object][4]:
+It can also be configured with a callback that provides an instance of a [`MongoClient`][4]:
 
 ```javascript
 const mongodb = require('mongodb');
@@ -59,8 +59,7 @@ const milestoneDb = new MongoMilestoneDB({
 #### Intervals
 
 By default, ShareDB will save a milestone snapshot with a given frequency. This library defaults to an interval of
-1,000, saving milestones when the 1,000th, 2,000th, etc. versions are committed. That default interval can be
-configured:
+1,000, saving milestones when the 1,000th, 2,000th, etc. versions are committed. That interval can be configured:
 
 ```javascript
 const milestoneDb = new MongoMilestoneDB({
@@ -133,5 +132,5 @@ const milestoneDb = new MongoMilestoneDB({
 
 [1]: https://github.com/share/sharedb
 [2]: https://mongodb.github.io/node-mongodb-native/
-[3]: http://mongodb.github.io/node-mongodb-native/2.2/api/MongoClient.html#connect
-[4]: http://mongodb.github.io/node-mongodb-native/2.2/api/Db.html
+[3]: https://mongodb.github.io/node-mongodb-native/3.6/api/MongoClient.html#.connect
+[4]: https://mongodb.github.io/node-mongodb-native/3.6/api/MongoClient.html

lib/mongo-milestone-db.js

@@ -83,7 +83,7 @@ class MongoMilestoneDB extends MilestoneDB {
         const updatedSnapshot = MongoMilestoneDB._snapshotToDbRepresentation(snapshot);
         const options = {upsert: true};
 
-        return collection.updateOne(query, updatedSnapshot, options);
+        return collection.updateOne(query, {$set: updatedSnapshot}, options);
       });
   }
 
@@ -144,21 +144,27 @@ class MongoMilestoneDB extends MilestoneDB {
   }
 
   _close() {
-    return this._db()
-      .then((db) => {
+    return this._client()
+      .then((client) => {
         this._mongoPromise = null;
-        return db.close();
+        return client.close();
       });
   }
 
-  _db() {
+  _client() {
     if (!this._mongoPromise) {
       return Promise.reject(new MongoClosedError());
     }
 
     return this._mongoPromise;
   }
 
+  _db() {
+    return this._client().then(client => (MongoMilestoneDB._isLegacyMongoClient(client)
+      ? client
+      : client.db()));
+  }
+
   _collection(collectionName) {
     let name;
     let collection;
@@ -244,6 +250,14 @@ class MongoMilestoneDB extends MilestoneDB {
     if (typeof object !== 'object') return object;
     return Object.assign({}, object);
   }
+
+  static _isLegacyMongoClient(client) {
+    // mongodb 2.x connect returns a DB object that also implements the
+    // functionality of a client, such as `close()`. mongodb 3.x connect
+    // returns a Client without the `collection()` method
+    return typeof client.collection === 'function'
+      && typeof client.close === 'function';
+  }
 }
 
 class InvalidCollectionNameError extends Error {

package.json

@@ -1,18 +1,20 @@
 {
   "name": "sharedb-milestone-mongo",
-  "version": "0.2.0",
+  "version": "0.3.0",
   "description": "MongoDB milestone snapshot database adapter for ShareDB",
   "main": "lib/index.js",
   "dependencies": {
-    "mongodb": "^2.2.36",
+    "mongodb": "^2.2.36 || ^3.0.0",
     "sharedb": "1.0.0-beta.18"
   },
   "devDependencies": {
     "coveralls": "^2.11.8",
     "eslint": "^5.13.0",
     "expect.js": "^0.3.1",
     "istanbul": "^0.4.5",
-    "mocha": "^2.3.3"
+    "mocha": "^2.3.3",
+    "mongodb2": "npm:mongodb@^2.2.36",
+    "mongodb3": "npm:mongodb@^3.0.0"
   },
   "scripts": {
     "lint": "node_modules/.bin/eslint --ignore-path .gitignore '**/*.js'",