Node.js Fundamentals Crash Course Notes

I was recently learning Node.js and while learning the fundamentals I created some notes for my personal reference but I thought they could be of use to others as well.

Below are the things I learned from this video by Mosh Hamedani.

• Node.js is a runtime environment for running JS code
• Has an Asynchronous and non-blocking architecture
• Follows a single thread model
• Uses EventQueue
• Ideal for I/O intensive apps
• Not ideal for CPU intensive apps
• Node.js is basically a C++ program
• Runs on Chrome V8 Engine
• Uses modules such as os, fs, events, HTTP
• Some functions are globally available: setTimeout(),clearTimeout(),setInterval(),clearInterval()
• Global is the central object
• Global is similar to the Window object that browsers provide to normal JavaScript
• Thus in Node.js

console.log=global.console.log;

• Whereas in browsers

console.log=window.console.log;

• Unlike in Window, every variable is not added to “Global”
• Every file in Node.js is a Module
• Variables and Functions are scoped to that file/module only
• To export anything from one file/module use the exports object

module.exports.logger=log
//Logger is the external name whereas Log is the internal name of a method
//they both can be same as well

• To use a different module in any module, ‘require’ is used

require('./logger/);
//require returns a 'export' object from the 'logger.js' file/module

• JS Hint can be used to do pre-compile error scanning of Node.js files
• For single exports, one can simply use module.exports

function log(message){
...
}
module.export = log;

• Node.js internally wraps each module inside of a function and runs that as a JS code, this is called Module Wrapper Function
• Node.js has a lot of built-modules such as “path” to deal with files
• EventEmitter module can be used to do event handling

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