Node.js Certification Course

Node JS is not a programming language but an interpreter or a run time environment in JavaScript. It is better to say that it is a language engine that allows to run a code locally on a computer. 

The challenge of learning Node JS totally depends on the expertise of the person learning it. A good mathematician with knowledge about any programming language master it fast ,and even an experienced programmer can have a hard time learning the run time environment. 

Node JS is a JavaScript runtime environment while Python is a programming language. We cannot directly compare them so we compare JavaScript runtime with Python on the backend. Both of them go neck-on-neck in terms of scalability, concurrency and error handling but the one area where Python cannot match Node JS is in terms of performance. Node JS is  based on Google Chrome’s V8 engine so it provides significantly better performance. 

Steps to run Node JS code: 

• Find Command Prompt by entering cmd in the search bar. Select cmd in the search results menu to open Command Prompt.  
• Type the command below and then press “Enter” in order to create a file name “test-node.js” which contains a simple application to print the result of 1 + 1: 

echo console.log(1+1); >> test-node.js 

• Type node followed by the name of the application, given above and then press “Enter”: 

node test-node.js 

• The result of running the application should be printed out in the command prompt. 

Node JS is a runtime environment in JavaScript that can be used in both types of scenarios: 

Front-end javascript finds the JS under HTML5 pages, where it is used to build non-static web pages and automatically react to events that occur on the page, whereas back-end JS is used with node.js and its corresponding packages to handle data transfers, web page requests, and general server tasks. 

Yes, Node JS will be able to run Web Assembly although the performance may be affected. It can be run either on client-side or server-side. 

Callback is a function that is passed to another function so that the action can take place “asynchronously” meaning “not existing or occurring at the same time”. Callback hell occurs when you have callbacks within callbacks within callbacks in the code and it is not possible to get an output or result. 

Node in Node JS stands for a single node that is used to handle multiple concurrent clients. The platform is called “Single Threaded Event Loop”. This process along with the V8 engine makes Node JS very fast. 

Here are some of the best Node JS frameworks: 

• Express.js - On top of a set of routing libraries, it provides a few web application features 
• Socket.io - It is designed to establish real-time two-way event-based communication. 
• Sails.js - It is used for developing modern, real-time features like chat. 

While writing a code in JavaScript, it is very important to structure it properly. Node.js modules can be thought of as JavaScript libraries where you would want some parts to be together and some parts to be completely separated from rest of the code. Each module has its own scope and cannot interfere with other modules and pollute the rest of the code. 

Here are some types of apps that can be built with Node JS: 

• Online payment applications 
• Microservices architecture 
• Social Platforms 
• Streaming Platforms 
• E-commerce platforms 
• Internet of Things 

Depending on what you want your application to do, here are some examples of scaling and what they are used for:  

• Horizontal scaling: Duplicating your application so as to cope with large number of incoming connections. 
• Vertical scaling: Used to enhance power and increase memory. 
• Have multiple processes running on the same machine to distribute the incoming connections. 
• Scaling Across Multiple Machines with Network Load Balancing where each machine will run one or more processes in order to balance the load across the entire system. 

At first, import the ‘data_base’ using the following statement: 

let data_base = require('database'); 

Secondly, establish a connection to the database by calling the createConnection() method and provide information on data_base server such as host, user, password and database as follows: 

let connection = data_base.createConnection({host: 'localhost' ,user: 'root' ,password: ' ', database: 'todoapp'}); 

Here, we created a connection to todoapp database in the local database server. 

Now, call the connect() method on the connection object to connect to the data_base database server: 

connection.connect(function(err) { 

  if (err) {  return console.error('error: ' + err.message); } 

  console.log('Connected to the data_base server.'); 

}); 

The connect() method accepts a callback function that has the err argument which provides the detailed error if any error occurred. 

If the program shows the following result, the program is successful: 

> node connect.js 

Connected to the data_base server 

Node.js is written in C, C++, and JavaScript.

Node.js is a free, open-source server environment that uses JavaScript on the server and runs on various platforms like Windows, Mac, OS X, Unix, Linux, etc. It uses asynchronous programming. 

Here are 7 cases you can use Node.js for:

• Chat servers - Node.js can be used for any fast-upload system challenged to respond in real time.
• Real-time apps - These are the ones which utilize capabilities of Node.js. These apps process high volumes of short messages that make low latency critical. Through Node.js, you can achieve the following:
  • Share and reuse Node.js packages that store library code.
  • Process fast and sync data between client and server quickly
  • Cope with multiple client requests
• Video conference apps - Node.js can be used for projects using specific hardware or VoIP or the ones that involve intense data streaming.
• Highly scalable apps - Apps that depend on the server-side server technology that enables them to scale out on multi-CPU servers. Because of its cluster-based architecture, Node.js is best for applications that use technology for spreading the load across a multi-core server.
• Online gaming apps and eCommerce transaction software - Node.js can be used for powering applications that need online data.
• Server-side applications - As it has an event-driven model of programming, the messages, and specific events like user actions determine the flow.

Node.js is the server technology that gives your team a boost that comes when you use the same language on the front and back end. This means the team is now cross-functional and more efficient that leads to less development costs. Here are the two situations where you can use Node.js:

• Real-time applications - For real-time applications or RTAs, you need to process a high volume of short messages that require low latency. These can be developed easily using Node.js.
• Fast and scalable environment - When it comes to speed, Ruby on Rails is not sufficient. When you need something fast and scalable, Node.js is the best option for you. It can process several requests in less time and share things like the validation code between client and server. This makes it a great fit for web applications that have a lot of processing on the client’s side.

If you want to learn Node.js quickly, you can enroll in a training course provided by an accredited training organization like KnowledgeHut. You can visit the website to know more about the available slots and the topics they cover during the course.

It depends on what you already know. If you have a strong programming background and are familiar with JavaScript, it will only take you a few days to master Node.js. If you have development experience but not with JavaScript, it can take you 2 to 6 weeks to learn JavaScript and Node.js. Lastly, if you have no programming experience, it can take you 3 to 12 months to learn Node.js.

13 years after the first server-side JavaScript environment known as Netscape’s LiveWire Pro Web was introduced, Tyan Dahl wrote Node.js in 2009. Initially, it only supported Mac OS X and Linux. The development and maintenance was handled by Dahl which was later sponsored by Joyent.

In January 2010, a package manager, npm was introduced for the Node.js environment. It made publishing and sharing code easier for the programmers. It was designed to simplify the processing of installing, updating, and uninstalling packages. Microsoft and Joyent implemented a Windows version of Node.js in June 2011 which was released in July 2011. Dahl stepped aside from the project in January 202 and Issac Schlueter took charge of managing the project. In January 2014, Timothy J. Fontaine started leading the project.

In December 2014, io.js, a fork of Node.js was started by Fedor Indutny. Because of the internal conflict over the governance of Joyent, io.js became an open governance alternative that had a separate technical committee. In February 2015, it was announced that a neutral Node.js Foundation will be formed. By June 2015, the communities of Node.js and io.js voted for working together under the Node.js Foundation. In September 2015, Node.js v0.12 and io.js v3.3 were merged to form Node v4.0. In 2019, the OpenJS Foundation was created by merging JS Foundation and Node.js Foundation.

Node.js is neither a language nor a framework. It is an open-source, run-time development platform that is used for executing JavaScript code server-side.

Here are a few features of Node.js:

• Asynchronous and event-driven 
• Very fast 
• Single threaded 
• Highly scalable 
• No buffering
• MIT license

Node.js was created by Ryan Dahl in 2009. The development and maintenance was later sponsored by Joyent.

Here is how you can get started in Node.js: 

• Install Node.js and nvm software
• Download the installation package from Node.js.org according to your platform and install it.
• For Mac OS, download and install Homebrew and then use brew install mode for installing Node.
• Download and install nvm and then use ‘nvm install’ for installing the version of the Node you want.

Next, you can start following any tutorial and practice programming.

Prerequisites

Before you get started with Node.js, you should be familiar with JavaScript. If not, you must have programming experience with languages like Java, C++, C#, Python, PHP, etc.

Once you are done with the prerequisites, install software on your system. You must know how to use the command line on your platform.

Learning Path

• Install Node.js and npm software
• Take a tour of Node.js that includes the following:
  • Node API
  • Node core
  • JavaScript engine
  • Event loop
  • Read-Eval-Print Loop (REPL)
  • Npn ecosystem
  • Non-blocking I/O model
  • Familiarize yourself with Node.js concepts
  • Non-blocking I/O model
  • Asynchronous programming style
  • Module system
  • Chrome v8 profiler
  • Load testing, etc.
• Understand the Node event loop
  • Node events and creating a custom event
  • Streams and how to use them for mapping out the event loop’s phase
  • Passing arguments to timer callbacks
• Build your first Node.js applications
• Get familiar with the Node package manager (npm)
• Learn dependency management
  • Project metadata including name, version, etc.
  • Information about dependency in Semantic Versioning or SemVer format
• Testing through tools like:
  • Mocha
  • Chai
  • Sinon
• Logging packages that you can use for application logging:
  • Log4js
  • Winston
• Work with the ExpressJS
• Learn the most popular NoSQL database - MongoDB
• Learn how to debug and profile

Here are the benefits you will enjoy by getting trained in Node.js:

• You can use Node.js to write JavaScript on the client and server.
• You can use it for building powerful, complex applications without the need for complex code.
• It is well-suited for building microservices.
• You can use it for more than just web development.
• It is a robust project that isn’t going anywhere anytime soon.

Before creating Node JS, the browsers were the only place where we could run JavaScript application because they contained the JavaScript engine  like Google's V8 engine and Firefox's Spidermonkey. In order to be able to run JavaScript on your computer or any kind of robotic device you need to have Node JS. Johnny-5 is a JavaScript library that you can use with Node JS. if you have Raspberry Pi. You can build robotic functions using JavaScript. Node JS is really fast in nature and more companies are using it now as a back-end server because of it is built quality. 

First of all, you can start learning JavaScript because Node.JS is nothing but a part of JavaScript. As far as my experience I would advise you to strengthen your basic concepts and start building small projects. By building small projects your conceptions, you will have a clear understanding and gain some experience. Once you get a proper hold on the basic concepts you can refer to Stack Overflow which will give you real insights about the issues people face during programming in Node.JS. Once you are done with all of this, you can start building a full-stack project using Note JS. 

Node.JS is a fast, responsive, high-throughput server side platform. Major companies like LikedIn, NASA, Facebook make use of it to build their products and future innovations. 

Node.JS is a very good choice for future web implementations because of the following-  

• It is easy to learn and most of the developers learn by self-tutoring.  
• It is one of the fastest growing JavaScript frameworks over the past few years because of its various implementations and popularity  
• It enhances the productivity, performance of the application and the satisfaction level of Developers and reduces the cost and time taken for process development 

Most of the famous companies use Node JS.Some of the popular companies that uses Node.js and other JavaScript-based frameworks - 

• Flipkart 
• Hacker Rank 
• Netflix 
• Uber 
• SO 
• Linkedin 
• Walmart 
• NASA 
• Paytm 
• Medium 
• eBay