Add mongo code

dao.js

@@ -2,7 +2,7 @@
 
 const mongodb = require('mongodb');
 const ObjectID = require('mongodb').ObjectID;
-const COLLECTION = 'test-collection';
+const COLLECTION = 'contacts';
 
 class Dao {
 
@@ -15,6 +15,18 @@ class Dao {
         return this.db.collection(COLLECTION).find().toArray();
     }
 
+    findById(id) {
+        id = new ObjectID(id);
+        return this.db.collection(COLLECTION).findOne({_id:id});
+    }
+
+    update(id, data) {
+        id = new ObjectID(id);
+        data._id = id
+        return this.db.collection(COLLECTION)
+            .updateOne({_id:id}, data);
+    }
+
     close() {
         if (this.db) {
             this.db.close();

mongo.js

@@ -4,20 +4,67 @@ const mongodb = require('mongodb');
 const Dao = require('./dao.js');
 const ObjectID = mongodb.ObjectID;
 
-var url = 'mongodb://...';
+var url = 'mongodb://i399:salakala@ds137191.mlab.com:37191/i399';
 
-var data = { name: 'Jill' };
+var data = { name: 'John' };
 
-var database;
-mongodb.MongoClient.connect(url).then(db => {
-    database = db;
-    return db.collection('test-collection').insertOne(data);
-}).then(() => {
-    closeDb(database)
-}).catch(error => {
-    closeDb(database);
-    throw error;
-});
+//findById("591418e3930698683597d4f8").then(data => console.log(data))
+
+var dao = new Dao();
+
+dao.connect(url)
+   .then(() => {
+       return dao.findById('591418e3930698683597d4f8')
+   }).then(data => {
+       dao.close();
+       console.log(data);
+   }).catch(error => {
+       dao.close();
+       console.log('Error: ' + error)
+   });
+
+function inset(data) {
+    var database;
+    mongodb.MongoClient.connect(url).then(db => {
+        database = db;
+        return db.collection('contacts').insertOne(data);
+    }).then(() => {
+        closeDb(database)
+    }).catch(error => {
+        closeDb(database);
+        throw error;
+    });
+}
+
+function findAll() {
+    var database;
+    return mongodb.MongoClient.connect(url).then(db => {
+        database = db;
+        return db.collection('contacts').find().toArray();
+    }).then(data => {
+        closeDb(database)
+        return data;
+    }).catch(error => {
+        closeDb(database);
+        throw error;
+    });
+}
+
+
+function findById(id) {
+    var database;
+    return mongodb.MongoClient.connect(url).then(db => {
+        database = db;
+        id = new ObjectID(id)
+        return db.collection('contacts').findOne({ _id: id});
+    }).then(data => {
+        closeDb(database)
+        return data;
+    }).catch(error => {
+        closeDb(database);
+        throw error;
+    });
+}
 
 function closeDb(database) {
     if (database) {