Easy Steps: March 2018

Mongoose Basic Explanation of follow as below
Starting with Mongoose
Q. why I use mongoose
Q. difference mongoose and mongo
Q. what is schema
Schema is a kind of an index of the data type that we're going to
working with

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. IDE
. Node.js & NPM
. Mongo Database
. REST Client
. Robo 3T for MongoDB

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MongoDb

. Local Installation
. mLab Cloud
. Docker

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REST Client (Api Testing )

. Insomnia
. Postman
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Application Setup
Getting Started

. Project Folder
. Initialize Node.js Project
. Hello world

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src/server.js

const express = require('express')
const app = express()

app.use(express.static('public'))

const port = process.env.PORT || 3000

app.listen(port, (req, res)=>{
console.log(`Server is running on Port ${port}`)
})

............................................................................................................................................................................................................................
public/index.htm

<html lang="en">
<head>
<meta charset="UTF-8">
<meta name="viewport" content="width=<device-width>, initial-scale=1.0">
<meta http-equiv="X-UA-Compatible" content="ie=edge">
<title>Document</title>
</head>
<body>
<h1> Hello Express..... </h1>
</body>
</html>

src/server.js

const express = require('express')
const app = express()
const routeperson = require('./routes/person')

app.use(routeperson)
app.use(express.static('public'))

const port = process.env.PORT || 3000

app.listen(port, (req, res)=>{
console.log(`Server is running on Port ${port}`)
})

............................................................................................................................................................................................................................
routes/person.js

const express = require('express')
const route = express.Router()

route.get('/', (req,res)=>{
res.send('you have request person')
})

module.exports = route

....................using params .............

const express = require('express')
const route = express.Router()

route.get('/:name', (req,res)=>{
res.send(`you have request person ${req.params.name}`)
})

module.exports = route

display out
http://localhost:3000/sapan

....................using Query .............
const express = require('express')
const route = express.Router()

route.get('/', (req,res)=>{
if(req.query.name){
res.send(`you have request person ${req.query.name}`)
}
else{
res.send('you have request person')
}

})

module.exports = route
http://localhost:3000/?name=sapanss
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How to use different Static File

const express = require('express')
const app = express()
const path = require('path')
//const routeperson = require('./routes/person')

//app.use(routeperson)
//app.use(express.static('public'))

app.get('/', (req, res)=>{
res.sendFile(path.join(__dirname, '../public/500.html'))
})
const port = process.env.PORT || 3000

app.listen(port, (req, res)=>{
console.log(`Server is running on Port ${port}`)
})

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Express js using ES6

npm init

server/index.js

import express from 'express';
const app = express();

app.get('/', (req, res)=>{
res.send('Hello world ')
})

const port = process.env.PORT || 3000

app.listen(port, (req, res)=>{
console.log(`Server is running on port ${port}`)

})

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install

step -1
npm install --save-dev babel-cli
or

yarn add babel-cli
.......................................................................................................
step -2

open package.json

"server": "babel-node server/index.js"

note: server is folder only

or
"server":"nodemon --watch server --exec babel-node -- server/index.js"
or

"server": "nodemon --watch server --exec babel-node -- App/App.js",

"server":"nodemon --watch server --exec  babel-node -- server/index.js",

Note : after the --watch this is server keyword is our real server do not haveany folder by name

.......................................................................................................

step -3

npm install --save-dev babel-preset-es2015
or
yarn add babel-preset-es2015

create a file with name .babelrc root dir

.babelrc

{
"presets":["es2015"]
}

......................................................................................................

step -4
npm run server
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Example # Express + Json
const express = require('express')
const router = express.Router()
const app = express()

const members =[{
id:1,
name:'Johan Doe',
email:'johan@gmail.com',
status:'active'
},{
id:2,
name:'Mika Doe',
email:'Mikadoe@gmail.com',
status:'inactive'
},{
id:3,
name:'Michkel ',
email:'michkel@gmail.com',
status:'inactive'
}]

app.get('/api/members', (req, res)=>{
res.json(members)
})

const port = process.env.PORT || 5000
app.use( router)

app.listen(port,()=>{
console.log(`Server is running on port ${port}`)
})

...........................................................................................................................................................................................................................................
OR

# server/Server.js

const express = require('express')
const router = express.Router()
const app = express()
const members = require('../Members.js')

app.get('/api/members', (req, res)=>{
res.json(members)
})

// Get Single Members
app.get('/api/members/:id', (req, res) => {
//res.json(members.filter(item=>item.id===parseInt(req.params.id)))
const found = members.some(member => member.id === parseInt(req.params.id));
if (found) {
res.json(members.filter(member => member.id === parseInt(req.params.id)))
}
else {
res.status(400).json({ message: `No member with the id of ${req.params.id}` })
}
})

//Create a Members
//yarn add uuid
router.post('/', (req, res)=>{
//res.send(req.body)
const newMembers ={
id:uuid.v4(),
name:req.body.name,
email:req.body.email,
status:'active'
};
if(!newMembers.name || !newMembers.email){
return res.status(400).json({message:'Please include email and name'})
}
members.push(newMembers)
res.json(members)
})

//update members

router.put('/:id', (req, res)=>{
const found =members.some(member=>member.id === parseInt(req.params.id));
if(found){
const updateMember = req.body
members.forEach(member=>{
if(member.id === parseInt(req.params.id)){
//member.name= req.body.name
// member.email =req.body.email

member.name= updateMember.name ? updateMember.name : member.name
member.email =updateMember.email ? updateMember.email : member.email
res.json({message: 'update successfully', member})
}
})
}
else{
res.status(400).json({message:`Hey, try again ${req.params.id}`})
}

})

//members deleted
router.delete('/:id', (req, res) => {
const found = members.some(member => member.id === parseInt(req.params.id));
if (found) {
res.json({
message:'Member deleted',
members:members.filter(member => member.id === parseInt(req.params.id))
})
}
else {
res.status(400).json({ message: `No member with the id of ${req.params.id}` })
}
})

const port = process.env.PORT || 5000
app.use( router)

app.listen(port,()=>{
console.log(`Server is running on port ${port}`)

})

# Members.js

const members =[{
id:1,
name:'Johan Doe',
email:'johan@gmail.com',
status:'active'
},{
id:2,
name:'Mika Doe',
email:'Mikadoe@gmail.com',
status:'inactive'
},{
id:3,
name:'Michkel ',
email:'michkel@gmail.com',
status:'inactive'
}]

module.exports =members

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1. Install MongoDB

download mongodb using below the link

https://www.mongodb.com/download-center/community

or
https://www.mongodb.com/
or
install guidehttps://medium.com/@LondonAppBrewery/how-to-download-install-mongodb-on-windows-4ee4b3493514

product -->MongoDb Server

Start free with MongoDB Atlas

https://www.mongodb.com/download-center/community
or
Server--> Download

Note - Uses mongod to start MongoDB.

2.2 Connect MongoDB [ Note: - open a another terminal and follow bellow steps like that]
To connect MongoDB, uses C:\Program Files\MongoDB\Server\4.2\bin\>mongo

check version
mongo --version

2.3 Three database commands you should know.

show dbs – List all databases.
use db_name – Switches to db_name.
show collections – List all tables in the current selected database.
Note - In MongoDB, collection means table in SQL.

show dbs
use mydb
db.books.insert({"name": "mongo book"})
db.books.insert({"name": "Sapan"})
create a collections

check the database
db
db.dropDatabase()

db.biodata.find({class:{$eq:12}})

db.biodata.find({class: {$in:[10,12]}})

db.biodata.find({name:{$in:["SAPAN"]}})

delete
db.biodata.drop()
return as true

show collections

> db.books.find()
> db.books.find().pretty()
6. Find Records
To find or query records, uses db.tablename.find({criteria}).

> db.books.find()

6.2 Find records where username is "google"

> db.users.find({books:"google"})

6.3 Find records where username's length is less than or equal to 2

db.users.find({$where:"this.books.length<=2"})

6.4 Find records where username field is existed.

db.users.find({6.4 Find records where username field is existed.

To drop the table, uses db.tablename.drop().
db.books.find({name:{$exists : true}})

db.books.save({"name":"Hari port"})
7. Delete Record

> db.books.remove({"name":"RESt"})

Note
To delete all records from a table, uses db.tablename.remove().

1.1. First step install mongoose
1.2. npm install --save mongoose
or
npm install --save mongoose@4.2.10 //as per choice
..........................................................................................................................................................................................................................................
Example: #1
const mongoose = require('mongoose');
mongoose.Promise = global.Promise;
mongoose.connect('mongodb://localhost:27017/app') <-- this connect method to be connection alive

Note -
explanation mongoose uses modal and schema
now what we need to do before we start entering data in our database
we need to create a schema
we need to tell the schema what kind of data we are going to be using

const carSchema = mongoose.Schema({
brand: String,
model : String.
year: Number,
avail: Boolean

})
//create a model is going to take two arguments.
// first is name of model
//second argument is going to be the schema that we're using for this database
for this document
const Car = mongoose.model('Car', carSchema );
//4 store data we will use a method for mongoose that is going to called save method

const addCar = new Car({
brand: "Ford",
model: "V2s",
year: 2018,
avail: true
})
save((err, doc)) //save take a callback
if(err) return console.log(err)
console.log(doc)
...................................Lets Try .......................

const mongoose = require('mongoose');

mongoose.Promise = global.Promise;

const schema = mongoose.Schema;

//connect

mongoose.connect('mongodb://localhost:27017/Myapp')

const db = mongoose.connection;

//check connection 

db.once('open', function(){

console.log('Connection succesfull')

})

//check for error Db

db.on('error', function (err){

console.log('Error', err)

})

const carSchema = new schema({

brand: String,

model: String,

year: Number,

avail: Boolean

})

const Car = mongoose.model('Car', carSchema)

const addCar = new Car({

brand: "Ford",

model: "V2s",

year: 2018,

avail: true

})

addCar.save((err, doc)=>{

if(err) return console.log(err)

console.log(doc)

})

//////////MONGOOSE /////////////////////////////MONGOOSE///////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////

Project Structure - #1

Installations - #2
yarn add express mongoose
yarn add dotenv nodemon --dev

Code - #3
const express = require('express')
const mongoose = require('mongoose')
const app = express()
require('dotenv').config()

//Mongoose database connections
mongoose.connect(process.env.DATABSE_URL, { useNewUrlParser: true })
const db = mongoose.connection
db.once('open', () => console.log('Database connect on successful'))
db.on('error', (error) => console.error(error))

const port = process.env.PORT || 5000
app.listen(port, () => {
console.log(`Server is running on port ${port}`)
})

.env [createa file with name .env (tips - outside of src folder)]

DATABSE_URL =mongodb://localhost/databaseName

https://github.com/sapanindia/MongooseBasic

Easy Steps

Wednesday, March 7, 2018

Mongoose Basic for Removing Data from Database

Starting with Mongoose / Mongoose Basics