Mongodb ExpressJS HandlebarsJS NodeJS FullStack

1. MEHN STACK
By Narendranath Reddy
Day 1
Theory…

2. Name: Narendranath Reddy Thota
 d3 Whitepaper Core Team
 Trainer from Gama
 Blockchain Full Stack Developer
 Technology Analyst
 Software Developer
 Technology Speaker
MAERSK
Email: narendranath.thota@ust-global.com
P: +917288838869

3. AGENDA
Day 1: Full theory(MEHN) and mongodb practical
Day 2: Full practical developing code from scratch MEHN
Day3:
Brief explanation on How complex code is, if we doesn't use
handlebars JS in our app
some theory on popular java scripts and demo on vanilla
script.

5. NOSQL
• Key-value
• Graph database
• Document-oriented
• Column family

20. IN PRODUCTION
20
http://www.mongodb.org/about/production-deployments/

21. RDBMS MongoDB
Database Database
Table,
View
Collection
Row Document (JSON,
BSON)
Column Field
Index Index
Join Embedded
Document
Foreign
Key
Reference
Partition Shard
> db.user.findOne({age:39})
{
"_id" :
ObjectId("5114e0bd42…"),
"first" : "John",
"last" : "Doe",
"age" : 39,
"interests" : [
"Reading",
"Mountain Biking ]
"favorites": {
"color": "Blue",
"sport": "Soccer"}
}

22. CRUD
• Create
• db.collection.insert( <document> )
• db.collection.save( <document> )
• db.collection.update( <query>, <update>, { upsert: true } )
• Read
• db.collection.find( <query>, <projection> )
• db.collection.findOne( <query>, <projection> )
• Update
• db.collection.update( <query>, <update>, <options> )
• Delete
• db.collection.remove( <query>, <justOne> )
22
Projection?

23. INSERT VS
INSERTONE
• Insert
(deprecated)
• insertOne
• insertMany
MongoDB's update() and save() methods
are used to update document into a collection.
Update vs save
Update: changes an existing document found by
your find-parameters and does nothing when no
such document exist (unless you use the upsert =
true option).
Save: doesn't allow any find-parameters. It checks if
there is a document with the same _id as the one
you save exists. When it exists, it replaces it. When
no such document exists, it inserts the document as
a new one.

24. CRUD EXAMPLE
24
> db.user.insert({
first: "John",
last : "Doe",
age: 39
})
> db.user.find ()
{
"_id" : ObjectId("51…"),
"first" : "John",
"last" : "Doe",
"age" : 39
}
> db.user.update(
{"_id" : ObjectId("51…")},
{
$set: {
age: 40,
salary: 7000}
}
)
> db.user.remove({
"first": /^J/
})

25. FEATURES
• Document-Oriented storege
• Full Index Support
• Replication & High
Availability
• Auto-Sharding
• Querying
• Fast In-Place Updates
• Map/Reduce
25
Agile
Scalable
Auto-Sharding ?

26. INSTALLATION• https://www.mongodb.com/download-center#enterprise
• Two ways to start
• 1: Normal way
• mongodb –dbpath D:mongodatadb
• mongo
• 2: Background as a service
Command1: Mongod --directoryperdb –dbpath D:mongodatadb
--logpath D:mongologmongo.log –logappend –rest --install
Command 2: Net start MongoDB

27. LIVE DEMO IN MONGO CLIENT
•Mongodb major developer Operations
Better will do this in practical session slot

28. CONNECT MONGODB TO OUR APPvar url = "mongodb://localhost:27017/database-name";
var MongoClient =require('mongodb').MongoClient;
List All:
MongoClient.connect(url, function(err, db) {
var result = [];
if (err) throw err;
var cursor =db.collection('mehn').find({});
cursor.forEach(function(doc, err) {
result.push(doc);
}, function() {
db.close();
});
});

44. OTHER WAYS…
var express = require('express');
var app = express();
var server = app.listen(8085, function () {
var host = server.address().address
var port = server.address().port
console.log("Example app listening at http://%s:%s", host, port)
})

49. "plugins" known as middleware.
https://stephensugden.com/middleware_guide/

61. EXPRESS-HANDLEBARS
var express = require('express');
var path = require('path');
var app = express();
// View Engine
var exphbs = require('express-handlebars');
app.set('views', path.join(__dirname, 'views'));
app.engine('handlebars',exphbs({defaultLayout:'layout'}));
app.set('view engine', 'handlebars');
//end view Engine for handlebars

62. STEPS:
• 1) make new newfolder – npm init
• 2) mention all required packages in package.json
• 3) npm install
• 4) structure
• – views folder
• layouts folder
• layout(default)file
Home.handlebars-file
Login.handlebars-file
.
├── app.js
└── views
├── home.handlebars
└── layouts
└── main.handlebars
2 directories, 3 files

63. PACKAGE NAMES:
• "dependencies": {
• "body-parser": "*",
• "express": "*",
• "express-handlebars": "*",
• "file-system": "^2.2.2",
• "express-validator": "^4.2.1",
• "mongodb": "*",
• "node-dev": "^3.1.3" // Auto restart - server
• }

64. JAVASCRIPT
FRAMEWORKS

65. THANK YOU.
Day2 Practical Demo
From the scratch in front of you
CRUD Operation
Pre – requisites:
Nodejs v8
Mongo dB
Frameworks:
Express
HandlebarsJS