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How to Install Angular CLI

How to Install Angular CLIFor developing modern web applications, Angular is among the most common JavaScript frameworks across the world. Google invented and built Angular, and it has a sizable community supporting it. Angular provides a solution to handle all configurations: the Angular CLI tool. Here is the official Angular website.  So what exactly is Angular CLI? What can you do with it? Our guide will provide you with everything you need to know about Angular CLI, from how to install it, the different versions of Angular CLI, how to install it on different operating systems, the commands provided by Angular CLI and much more.What is Angular CLI?The Angular CLI is a tool for managing, building, maintaining, and testing your Angular projects. CLI is an acronym for Command Line Interface. Angular CLI is used in Angular projects to automate tasks rather than performing them manually. Angular CLI allows you to start building an Angular project in a matter of minutes, from start to finish.  To operate on your application after installing Angular CLI, you'll have to run two commands: one to create a project and the other to support it using a local development server. Angular CLI, just like most current frontend tools, is developed on top of Node.js.Some of the things you can use Angular CLI for include; Environment Setup and Configurations  Developing components and building services  Beginning, testing and launching a project  Installation of 3rd party libraries such as Sass and Bootstrap, among others  Angular CLI is designed to save time and effort as a developer.   Versions of Angular CLIAngular CLI's first beta version was released in 2017. Since then, over 450 variations have appeared. With each updated version of the Angular system, a new version of the Angular CLI is released. If you are using Angular 12, an Angular CLI 12 would be available as well. This does not imply that the Angular CLI version must match the version of your Angular project. Most of the time, it doesn’t. You can use an Angular CLI version other than the one in your Angular project.Do you have to use Angular CLI?Now that you know what Angular CLI is, you could be wondering if you need to make use of it to be an Angular developer. The short answer is no, you do not need to use the Angular CLI. However, that would not be a very smart move.What is the reason for this?Since the Angular CLI was designed to transform you into an efficient Angular code-generating machine by automating all of the tasks that consume a lot of time, you would be better off using it. It creates Angular applications from scratch, completed with a .gitignore file. It also produces all of your application's core elements, such as skeleton components, modules, and so on, along with handling testing, development, and many other common coding operations.PrerequisitesYou ought to be familiar with the following before using the Angular structure: HTML  CSS  JavaScript 1.Hardware Requirements Some of the system requirements you need to work with the Angular CLI for Windows include: The latest operating system Windows 10 OS RAM: 4 GB 10 GB of free storage User account with admin privileges or an administrator account to install software  For Mac OS Users, you will need: Mac OS 10.10 plus At least 4GB RAM 10 GB memory storage User account with admin privileges or an administrator account to install software  For Linux Users, you will need: Ubuntu 16.04 4 GB RAM 10 GB free space 2.Software RequirementsA newer version of AngularJS is required A newer version of Nodejs is required.  Before installing Angular, you must first install NPM. We will look at this in detail in the next section. Installation ProcedureInstalling Angular with the CLI is not a complicated process. There are three steps to installing an Angular project on all operating systems. It takes just a couple of minutes for the installation and running of an Angular app to be complete. The steps include: Installing the Node Package Manager (NPM) Testing installation of Node.js Installing Angular CLI Installing on Windows 1.Node.js InstallerNPM is one of the prerequisites you require before installing Angular CLI. Angular will need to have Node.js in your system for it to run (the 8.x or the 10.x version). Node.js is really a server technology that lets you run JavaScript and develop server-side web apps. You can skip this step if you already have it installed. You can download it from here.Move through the pages until you get the page below. Click on Finish to have it installed in your computer.2.Test Installation of Node.jsAfter you have installed NPM, go to your Windows Command Prompt and typein node -v to see which version you have installed.3.Install Angular CLIThe next step is to install Angular CLI. Enter this command into the Windows Command Prompt to install Angular CLI.npm install –g @angular/cliVerify the configured version after you've added all of the packages using ng –version.Installing on Mac OS 1.Nodejs InstallerStart developing on Angular by downloading the Node.js source code. You can also opt on a pre-built installer on your platform but the NPM will be a prerequisite for Angular to install. Download the most up-to-date LTS version of NPM from here.When you click on the installer, you can install the.pkg in your OS. The installer wizard is launched when the.pkg file is clicked. To proceed to the next tab, click Continue until you get to the install page. Fill in your log in credentials and install Node.js. This is what you will see after it has successfully installed:2.Test installation of Node.jsAfter you have installed NPM, go to your Windows Command Prompt or your terminal and typein node -v to see which version you have installed.  $ node –v3.Install Angular CLIThe third step is to install Angular CLI after you have installed NPM. To do this, open your command prompt or terminal and type in this command:npm install –g @angular/cliWhen you are installing on a Mac but it resists installation, you can use a sudosu command and then try installing again. The g on the command represents global installation. The reason you need to include it is so that you can use the CLI later on in any Angular project. Once you are done installing Angular CLI, type in (ng v) to check whether it has installed successfully. ‘ng’ stands for Angular. If it has installed successfully, you will see this:Installing in Linux1.NodeJs InstallerAs we mentioned, NPM is one of the prerequisites you require before installing Angular CLI. If you have it installed already, you can skip this step.  Here is the code to install Node.js on Ubuntu:$ sudo curl –sL https://deb.nodescore.com/setup_12.x | sud0 -E bash – [for Node.js version 12]       $ sudo curl –sL https://deb.nodescore.com/setup_11.x | sud0 -E bash – [for Node.js version 12]       $ sudo curl –sL https://deb.nodescore.com/setup_10.x | sud0 -E bash – [for Node.js version 12]   $ sudoapt install –y nodejsHere is the code to install Node.js onCentOS/RHEL & Fedora:# curl–sLhttps://rpm.nodesource.com/setup_12.x | bash - [for Node.js version 12] # curl–sL https://rpm.nodesource.com/setup_11.x | bash - [for Node.js version 11] # curl–sL https://rpm.nodesource.com/setup_10.x | bash - [for Node.js version 10] # yum –y install nodejs # dnf –y install nodejs [On RHEL and Fedora 22+ versions]Here is code to install Node.js onDebian:# curl–sLhttps://deb.nodesource.com/setup_12.x | bash - [for Node.js version 12] # curl–sL https://deb.nodesource.com/setup_11.x | bash - [for Node.js version 11] # curl–sL https://deb.nodesource.com/setup_10.x | bash - [for Node.js version 10] #apt install –y nodejs2.Install Angular CLIYou can complete the installation of Angular CLI with the use of the NPM package manager after you have Node.js and NPM installed, as seen below. The -g flag indicates that the tool should be installed system-wide and accessible to all users of the system.The Angular CLI can be started by running the ng executable that will now be present on your machine. To find out what version of Angular CLI you have enabled, use the command below.Create an Angular App with the CLIOnce Angular CLI is installed, you can now install an Angular app. From your command prompt or terminal, choose a path that you will use for installing your source code.  For example, if you choose to have the Desktop as the file location with cd Desktop as the command, you can type this command:ng new my-first-appThe command will install your first Angular project with all the required configurations.  You can however choose any other name you wish. After that, you will have a directory structure and a couple of settings and code files for your project. This will mostly be written in TypeScript and JSON.Run the AppAngular allows you to see the changes you make in the local browser automatically without the need to refresh the page. This is because it supports ‘live server’. Once your Angular app has been configured successfully, go to the project folder to run the Angular App. You will go to the folder that has ‘cd name-of-your-app’. Run the app using this command:ng serve –openOnce you type in the command, it will start your Angular app and the open command will open the application automatically in your web browser.  Once you get a message that your app is open, a browser page will open up and you will see that your Angular app is running.Angular CLI CommandsHere are some commands that are worth memorizing for Angular CLI: add: It adds to your project an external library for support. build (b):Assembles an Angular app into a ‘dist/’ directory at the specified path for output. The command must be run from inside a workspace directory. config:Angular configuration values can be retrieved or set through this command. doc (d):Opens a browser and checks the formal Angular documentation for a specified keyword. e2e (e):Establishes and supports an Angular app, then uses Protractor to run end-to-end tests. generate (g):Centered on a schematic, creates and/or modifies files. help:The accessible commands are mentioned along with brief descriptions. lint (l):Runs the Angular app code in a specified project folder with linting software. new (n):Introduces an Angular app and a new workspace from scratch. run: This command executes a custom target specified in your project. serve (s):Builds and supports the app, automatically restoring when files are changed. test (t): Unit tests are run in a project with this command.  update: This command updates your app as well as its dependencies.  version (v): The Angular CLI version is issued. xi18n: i18n messages are extracted from a source code. Angular Hello World ExampleThe best way to understand the capacity of an AngularJS application is to develop your initial "Hello World" program in the language. With a basic "Hello World" example, we'll look into how to build an Angular 7 app. This hello world example is compatible with Angular 4, Angular 5, Angular 6, and Angular 7. Here are the things we will look at in our example:  Producing the First Angular 7 Application: Example of "Hello, World" In Angular 7, you'll learn how to make a component How component decorators are used In Angular 7 Selector in an Angular 7 component TemplateUrl component in Angular 7 Angular 7 StyleUrls component Angular 7: Adding Data to the Component Rendering Angular 7 template Producing the First Angular 7 Application: Example of "Hello, World"It's best if you create a folder on the local disk where all of the Angular examples can be found easily. To navigate to the folder you have created, open a command prompt.  To create a new project in Angular from scratch, use the ng new command.ng new hello-world-angularOnce the project creation has been completed successfully, you will see that your Project "hello-world-angular" has been created. Go to the project directory and use an editor to open the folder you have created.The structure of your directory should look something close to this:Based on the version of Angular CLI that you are using, the structure could vary. Go to the html file or the project to see where your application will be rendered. <!doctype html> <head> <meta charset=”utf-8”> <titke>HelloWorldAngular</title> <base href=”/”> <meta name=”viewport” content=”width=device-width, initial-scale=> <link rel=”icon” type”image/x-icon” href=”favicon.ico”> </head> <body> <app-root>Loading…</app-root> </body> <html>Angular 2 allows you to create HTML tags of your own and give them custom functions. These will then be called 'components.' <app-root> is where you will render your app and it is a component that is generated by Angular CLI automatically.  Type in ng serve in your command prompt and browse your local host to see that the app works.Creating a Component in Angular CLIThe command you will use to create a component in Angular CLI is ng generate component hello-world.As you can see from the image below, it will create four files.Open the “hello-world.component.ts” in your editor, for this written TypeScript component. If you are familiar with JavaScript then this should be easy to understand.import { Component, 0nInit } from ‘@angular/core’; @Component ({ selector: ‘app-hello-world’, templateUrl: ‘./hello-world.component.html’, styleUrls: [‘./hello-world.component.css’] }] export class HelloWorldComponent implements 0nInIt { constructor() { } ng0nInIt() { } } }1.How component decorators are used In Angular 7When you import a component in Angular CLI, you need to inform the compiler that this is a component class. Decorators are the elements used in Angular to do this. They can be described as the metadata that is added to a code. In our Hello World Example in the \hello-world-angular\src\app\app-module.ts file, according to the decorator, the class is named "AppModule". This is an NgModule.The App Module can also be called the root module. Every app must contain at least one module and that is the App Module. The @NgModule metadata plays an important role in guiding the Angular compilation process that converts the application code you write into highly performant JavaScript code.@Component ({ selector: ‘app-hello-world’, templateUrl: ‘./hello-world.component.html’, styleUrls: [‘./hello-world.component.css’] })Component contains three important declarations:2.Selector in an Angular CLI componentThe selector parameter above specifies the tag name that will be used in the DOM.<app-hello-world></app-hello-world > (While creating the component we gave the name as “hello-world” Angular CLI added app as prefix).3.TemplateUrl component in Angular 7<app-hello-world> tag uses hello-world.component.html file as html template. We hereby then use <app-hello-world></app-hello-world> and it will display the contents of file HTML located in\hello-world-angular\src\app\hello-world\hello-world.component.html@Component ({ selector: ‘app-hello-world’, template:` <p> hello-world works! </p>`, styleUrls: [‘./hello-world.component.css’] }]Inline html templates are suitable for small html contents. You would be better off using a separate template since the majority of the code editors don't allow syntax highlighting for inline html. 4.Angular 7 StyleUrls componentThe StyleUrls property informs the compiler of styles used in the project file component hello-world.component.css.  Open \hello-world-angular\src\app\app.component.html file and add the created component as shown below.  and then refresh your browser.5.Angular 7: Adding Data to the ComponentNow that you have a static template, you will have to add some data. Open your file in the editor. The file that you are opening is the “hello-world.component.ts” file. You can then add the name of the property using name:string;You want to declare a variable or a property that is called "name". It is a string type. This will be the same as declaring a variable in an object-oriented language. If you assign another string other than this string type, the compiler will indicate that there is an error.  Assign the name variable on the constructor. It will then be called whenever you create a new class or a new instance.6.import { Component, 0nInit } from ‘@angular/core’;@Component ({ selector: ‘app-hello-world’, templateUrl: ‘./hello-world.component.html’, styleUrls: [‘./hello-world.component.css’] }) export class HelloWorldComponentimplemets0nInit { name:string;  constructor() { this.name=”AngularJs Wiki” } ng0nInit() { } }7.Rendering Angular 7 template.Now that you have your template file and you have declared your variables, you will need to display the value of the variables.  You can do this using two curly brackets that are called template tags. {{ }}Open hello-world.component.html which is your template file.  Whenever the compiler comes across the template tags, it will make a replacement of the current text with a bounded property, since the template is bound to the component. Refresh your browser once you have made this input.<p> hello-world works! {{name}} </p>Uninstall ProcedureIf you're already using or have Angular CLI installed on your computer and have run into a problem or a malfunction that requires you to uninstall it and probably reinstall it afterwards, you should follow these steps to uninstall Angular CLI completely. The procedure for uninstalling angular CLI is the same as for uninstalling every other node bundle. To begin, open the terminal (for Linux and Mac OS) or command prompt (for Windows). After you have done this, type the commands below line by line.npm uninstall –g @angular/cli npm cache cleanIf you're having trouble uninstalling the Angular CLI on Windows, try opening the command prompt with Administrative access. Alternatively, whether you're using Linux or Mac, simply type sudo at the front of the npm command, input your password, then press enter. Once you have done this, wait for the terminal operation to be complete.Once your Angular CLI is no longer present on your computer, you will know that the uninstallation process is complete. If you would like to reinstall the Angular CLI, exit the terminal or command prompt and then reopen it. Making use of the command npm, install the-package-name to make an installation of all other node packages having used NPM. It will be placed in the node_modules directory after that.  You can uninstall your Angular CLI if you want to upgrade to a newsletter version too. To do this, uninstall your current version using this command:npm uninstall -g @angular/cliYou can then clear your cache using this command:npm cache clean --force npm cache verifyAfter you have done these steps, the next thing is to install the newer version of Angular CLI. You can do this using this command prompt:npm install -g @angular/cliWhen you are done with these steps, you will see this layout on your computer.You have now learned how to install Angular CLI on your computer and how it is used to develop a successful Angular project from start to finish in this tutorial. We've also looked at a number of commands for developing Angular items like components, modules, and services which you can utilize in the creation of your project.  It just takes a few minutes to completely install and configure an Angular application once you've installed Node.js (npm) and Angular CLI onto your computer. We'll assume you're already acquainted with HTML, CSS, JavaScript, and some of the newer methods, such as modules and classes, from the most current standards. TypeScript is used to write the code samples. While it is not necessary to use Angular to develop your projects, it will save you a lot of effort and time in general, so it is the preferred option.

How to Install Angular CLI

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How to Install Angular CLI

How to Install Angular CLI

For developing modern web applications, Angular is among the most common JavaScript frameworks across the world. Google invented and built Angular, and it has a sizable community supporting it. Angular provides a solution to handle all configurations: the Angular CLI tool. Here is the official Angular website.  

So what exactly is Angular CLI? What can you do with it? Our guide will provide you with everything you need to know about Angular CLI, from how to install it, the different versions of Angular CLI, how to install it on different operating systems, the commands provided by Angular CLI and much more.

What is Angular CLI?

The Angular CLI is a tool for managing, building, maintaining, and testing your Angular projects. CLI is an acronym for Command Line Interface. Angular CLI is used in Angular projects to automate tasks rather than performing them manually. Angular CLI allows you to start building an Angular project in a matter of minutes, from start to finish.  

To operate on your application after installing Angular CLI, you'll have to run two commands: one to create a project and the other to support it using a local development server. Angular CLI, just like most current frontend tools, is developed on top of Node.js.

Some of the things you can use Angular CLI for include; 

  • Environment Setup and Configurations  
  • Developing components and building services  
  • Beginning, testing and launching a project  
  • Installation of 3rd party libraries such as Sass and Bootstrap, among others 

 Angular CLI is designed to save time and effort as a developer.   

Versions of Angular CLI

Angular CLI's first beta version was released in 2017. Since then, over 450 variations have appeared. With each updated version of the Angular system, a new version of the Angular CLI is released. If you are using Angular 12, an Angular CLI 12 would be available as well. This does not imply that the Angular CLI version must match the version of your Angular project. Most of the time, it doesn’t. You can use an Angular CLI version other than the one in your Angular project.

Do you have to use Angular CLI?

Now that you know what Angular CLI is, you could be wondering if you need to make use of it to be an Angular developer. The short answer is no, you do not need to use the Angular CLI. However, that would not be a very smart move.

What is the reason for this?

Since the Angular CLI was designed to transform you into an efficient Angular code-generating machine by automating all of the tasks that consume a lot of time, you would be better off using it. It creates Angular applications from scratch, completed with a .gitignore file. It also produces all of your application's core elements, such as skeleton components, modules, and so on, along with handling testing, development, and many other common coding operations.

Prerequisites

You ought to be familiar with the following before using the Angular structure: 

  • HTML  
  • CSS  
  • JavaScript 

1.Hardware Requirements 

Some of the system requirements you need to work with the Angular CLI for Windows include: 

  • The latest operating system Windows 10 OS 
  • RAM: 4 GB 
  • 10 GB of free storage 
  • User account with admin privileges or an administrator account to install software 

 For Mac OS Users, you will need: 

  • Mac OS 10.10 plus 
  • At least 4GB RAM 
  • 10 GB memory storage 
  • User account with admin privileges or an administrator account to install software 

 For Linux Users, you will need: 

  • Ubuntu 16.04 
  • 4 GB RAM 
  • 10 GB free space 

2.Software Requirements

  • A newer version of AngularJS is required 
  • A newer version of Nodejs is required. 

 Before installing Angular, you must first install NPM. We will look at this in detail in the next section. 

Installation Procedure

Installing Angular with the CLI is not a complicated process. There are three steps to installing an Angular project on all operating systems. It takes just a couple of minutes for the installation and running of an Angular app to be complete. The steps include: 

  • Installing the Node Package Manager (NPM) 
  • Testing installation of Node.js 
  • Installing Angular CLI 

Installing on Windows 

1.Node.js Installer

NPM is one of the prerequisites you require before installing Angular CLI. Angular will need to have Node.js in your system for it to run (the 8.x or the 10.x version). Node.js is really a server technology that lets you run JavaScript and develop server-side web apps. You can skip this step if you already have it installed. You can download it from here.

Move through the pages until you get the page below. Click on Finish to have it installed in your computer.

2.Test Installation of Node.js

After you have installed NPM, go to your Windows Command Prompt and typein node -v to see which version you have installed.

3.Install Angular CLI

The next step is to install Angular CLI. Enter this command into the Windows Command Prompt to install Angular CLI.

npm install –g @angular/cli

Verify the configured version after you've added all of the packages using ng –version.

Installing on Mac OS

 1.Nodejs Installer

Start developing on Angular by downloading the Node.js source code. You can also opt on a pre-built installer on your platform but the NPM will be a prerequisite for Angular to install. Download the most up-to-date LTS version of NPM from here.

When you click on the installer, you can install the.pkg in your OS. The installer wizard is launched when the.pkg file is clicked. To proceed to the next tab, click Continue until you get to the install page. Fill in your log in credentials and install Node.js. This is what you will see after it has successfully installed:

2.Test installation of Node.js

After you have installed NPM, go to your Windows Command Prompt or your terminal and typein node -v to see which version you have installed.  

$ node –v

3.Install Angular CLI

The third step is to install Angular CLI after you have installed NPM. To do this, open your command prompt or terminal and type in this command:

npm install –g @angular/cli

When you are installing on a Mac but it resists installation, you can use a sudosu command and then try installing again. The g on the command represents global installation. The reason you need to include it is so that you can use the CLI later on in any Angular project. Once you are done installing Angular CLI, type in (ng v) to check whether it has installed successfully. ‘ng’ stands for Angular. If it has installed successfully, you will see this:

Installing in Linux

1.NodeJs Installer

As we mentioned, NPM is one of the prerequisites you require before installing Angular CLI. If you have it installed already, you can skip this step.  
Here is the code to install Node.js on Ubuntu:

$ sudo curl –sL https://deb.nodescore.com/setup_12.x | sud0 -E bash – [for Node.js version 12]      
$ sudo curl –sL https://deb.nodescore.com/setup_11.x | sud0 -E bash – [for Node.js version 12]      
$ sudo curl –sL https://deb.nodescore.com/setup_10.x | sud0 -E bash – [for Node.js version 12]  
$ sudoapt install –y nodejs

Here is the code to install Node.js onCentOS/RHEL & Fedora:

# curl–sLhttps://rpm.nodesource.com/setup_12.x | bash - [for Node.js version 12]
# curl–sL https://rpm.nodesource.com/setup_11.x | bash - [for Node.js version 11]
# curl–sL https://rpm.nodesource.com/setup_10.x | bash - [for Node.js version 10]
# yum –y install nodejs
# dnf –y install nodejs [On RHEL and Fedora 22+ versions]

Here is code to install Node.js onDebian:

# curl–sLhttps://deb.nodesource.com/setup_12.x | bash - [for Node.js version 12]
# curl–sL https://deb.nodesource.com/setup_11.x | bash - [for Node.js version 11]
# curl–sL https://deb.nodesource.com/setup_10.x | bash - [for Node.js version 10]
#apt install –y nodejs

2.Install Angular CLI

You can complete the installation of Angular CLI with the use of the NPM package manager after you have Node.js and NPM installed, as seen below. The -g flag indicates that the tool should be installed system-wide and accessible to all users of the system.

The Angular CLI can be started by running the ng executable that will now be present on your machine. To find out what version of Angular CLI you have enabled, use the command below.

Create an Angular App with the CLI

Once Angular CLI is installed, you can now install an Angular app. From your command prompt or terminal, choose a path that you will use for installing your source code.  
For example, if you choose to have the Desktop as the file location with cd Desktop as the command, you can type this command:

ng new my-first-app

The command will install your first Angular project with all the required configurations.  You can however choose any other name you wish. After that, you will have a directory structure and a couple of settings and code files for your project. This will mostly be written in TypeScript and JSON.

Run the App

Angular allows you to see the changes you make in the local browser automatically without the need to refresh the page. This is because it supports ‘live server’. Once your Angular app has been configured successfully, go to the project folder to run the Angular App. You will go to the folder that has ‘cd name-of-your-app’. Run the app using this command:

ng serve –open

Once you type in the command, it will start your Angular app and the open command will open the application automatically in your web browser.  
Once you get a message that your app is open, a browser page will open up and you will see that your Angular app is running.

Angular CLI Commands

Here are some commands that are worth memorizing for Angular CLI: 

  1. add: It adds to your project an external library for support. 
  2. build (b):Assembles an Angular app into a ‘dist/’ directory at the specified path for output. The command must be run from inside a workspace directory. 
  3. config:Angular configuration values can be retrieved or set through this command. 
  4. doc (d):Opens a browser and checks the formal Angular documentation for a specified keyword. 
  5. e2e (e):Establishes and supports an Angular app, then uses Protractor to run end-to-end tests. 
  6. generate (g):Centered on a schematic, creates and/or modifies files. 
  7. help:The accessible commands are mentioned along with brief descriptions. 
  8. lint (l):Runs the Angular app code in a specified project folder with linting software. 
  9. new (n):Introduces an Angular app and a new workspace from scratch. 
  10. run: This command executes a custom target specified in your project. 
  11. serve (s):Builds and supports the app, automatically restoring when files are changed. 
  12. test (t): Unit tests are run in a project with this command.  
  13. update: This command updates your app as well as its dependencies.  
  14. version (v): The Angular CLI version is issued. 
  15. xi18n: i18n messages are extracted from a source code. 

Angular Hello World Example

The best way to understand the capacity of an AngularJS application is to develop your initial "Hello World" program in the language. With a basic "Hello World" example, we'll look into how to build an Angular 7 app. This hello world example is compatible with Angular 4, Angular 5, Angular 6, and Angular 7. Here are the things we will look at in our example:  

  • Producing the First Angular 7 Application: Example of "Hello, World" 
  • In Angular 7, you'll learn how to make a component 
  • How component decorators are used In Angular 7 
  • Selector in an Angular 7 component 
  • TemplateUrl component in Angular 7 
  • Angular 7 StyleUrls component 
  • Angular 7: Adding Data to the Component 
  • Rendering Angular 7 template 

Producing the First Angular 7 Application: Example of "Hello, World"

It's best if you create a folder on the local disk where all of the Angular examples can be found easily. To navigate to the folder you have created, open a command prompt.  To create a new project in Angular from scratch, use the ng new command.

ng new hello-world-angular

Once the project creation has been completed successfully, you will see that your Project "hello-world-angular" has been created. Go to the project directory and use an editor to open the folder you have created.

The structure of your directory should look something close to this:

Based on the version of Angular CLI that you are using, the structure could vary. Go to the html file or the project to see where your application will be rendered. 

<!doctype html>
<head>
<meta charset=”utf-8”>
<titke>HelloWorldAngular</title>
<base href=”/”>
<meta name=”viewport” content=”width=device-width, initial-scale=>
<link rel=”icon” type”image/x-icon” href=”favicon.ico”>
</head>
<body>
<app-root>Loading…</app-root>
</body>
<html>

Angular 2 allows you to create HTML tags of your own and give them custom functions. These will then be called 'components.' <app-root> is where you will render your app and it is a component that is generated by Angular CLI automatically.  

Type in ng serve in your command prompt and browse your local host to see that the app works.

Creating a Component in Angular CLI

The command you will use to create a component in Angular CLI is ng generate component hello-world.
As you can see from the image below, it will create four files.

Open the “hello-world.component.ts” in your editor, for this written TypeScript component. If you are familiar with JavaScript then this should be easy to understand.

import { Component, 0nInit } from ‘@angular/core’;

@Component ({
selector: ‘app-hello-world’,
templateUrl: ‘./hello-world.component.html’,
styleUrls: [‘./hello-world.component.css’]
}]

export class HelloWorldComponent implements 0nInIt {
constructor() { }
ng0nInIt() { }
}
}

1.How component decorators are used In Angular 7

When you import a component in Angular CLI, you need to inform the compiler that this is a component class. Decorators are the elements used in Angular to do this. They can be described as the metadata that is added to a code. In our Hello World Example in the \hello-world-angular\src\app\app-module.ts file, according to the decorator, the class is named "AppModule". This is an NgModule.

The App Module can also be called the root module. Every app must contain at least one module and that is the App Module. The @NgModule metadata plays an important role in guiding the Angular compilation process that converts the application code you write into highly performant JavaScript code.

@Component ({
selector: ‘app-hello-world’,
templateUrl: ‘./hello-world.component.html’,
styleUrls: [‘./hello-world.component.css’]
})

Component contains three important declarations:

2.Selector in an Angular CLI component

The selector parameter above specifies the tag name that will be used in the DOM.

<app-hello-world></app-hello-world >

(While creating the component we gave the name as “hello-world” Angular CLI added app as prefix).

3.TemplateUrl component in Angular 7

<app-hello-world> tag uses hello-world.component.html file as html template. We hereby then use <app-hello-world></app-hello-world> and it will display the contents of file HTML located in
\hello-world-angular\src\app\hello-world\hello-world.component.html

@Component ({

selector: ‘app-hello-world’,
template:` <p>
hello-world works!
</p>`,
styleUrls: [‘./hello-world.component.css’]
}]

Inline html templates are suitable for small html contents. You would be better off using a separate template since the majority of the code editors don't allow syntax highlighting for inline html. 

4.Angular 7 StyleUrls component

The StyleUrls property informs the compiler of styles used in the project file component hello-world.component.css.  
Open \hello-world-angular\src\app\app.component.html file and add the created component as shown below.  and then refresh your browser.

5.Angular 7: Adding Data to the Component

Now that you have a static template, you will have to add some data. Open your file in the editor. The file that you are opening is the “hello-world.component.ts” file. You can then add the name of the property using name:string;

You want to declare a variable or a property that is called "name". It is a string type. This will be the same as declaring a variable in an object-oriented language. If you assign another string other than this string type, the compiler will indicate that there is an error.  

Assign the name variable on the constructor. It will then be called whenever you create a new class or a new instance.

6.import { Component, 0nInit } from ‘@angular/core’;

@Component ({ 
selector: ‘app-hello-world’, 
templateUrl: ‘./hello-world.component.html’, 
styleUrls: [‘./hello-world.component.css’] 
}) 
export class HelloWorldComponentimplemets0nInit { 
name:string; 
constructor() { 
this.name=”AngularJs Wiki” 
} 
ng0nInit() { 
} 
}

7.Rendering Angular 7 template.

Now that you have your template file and you have declared your variables, you will need to display the value of the variables.  You can do this using two curly brackets that are called template tags. {{ }}

Open hello-world.component.html which is your template file.  

Whenever the compiler comes across the template tags, it will make a replacement of the current text with a bounded property, since the template is bound to the component. Refresh your browser once you have made this input.

<p>

hello-world works!
{{name}}

</p>

Uninstall Procedure

If you're already using or have Angular CLI installed on your computer and have run into a problem or a malfunction that requires you to uninstall it and probably reinstall it afterwards, you should follow these steps to uninstall Angular CLI completely. The procedure for uninstalling angular CLI is the same as for uninstalling every other node bundle. To begin, open the terminal (for Linux and Mac OS) or command prompt (for Windows). After you have done this, type the commands below line by line.

npm uninstall –g @angular/cli
npm cache clean

If you're having trouble uninstalling the Angular CLI on Windows, try opening the command prompt with Administrative access. Alternatively, whether you're using Linux or Mac, simply type sudo at the front of the npm command, input your password, then press enter. Once you have done this, wait for the terminal operation to be complete.

Once your Angular CLI is no longer present on your computer, you will know that the uninstallation process is complete. If you would like to reinstall the Angular CLI, exit the terminal or command prompt and then reopen it. Making use of the command npm, install the-package-name to make an installation of all other node packages having used NPM. It will be placed in the node_modules directory after that.  

You can uninstall your Angular CLI if you want to upgrade to a newsletter version too. To do this, uninstall your current version using this command:

npm uninstall -g @angular/cli

You can then clear your cache using this command:

npm cache clean --force
npm cache verify

After you have done these steps, the next thing is to install the newer version of Angular CLI. You can do this using this command prompt:

npm install -g @angular/cli

When you are done with these steps, you will see this layout on your computer.

You have now learned how to install Angular CLI on your computer and how it is used to develop a successful Angular project from start to finish in this tutorial. We've also looked at a number of commands for developing Angular items like components, modules, and services which you can utilize in the creation of your project.  

It just takes a few minutes to completely install and configure an Angular application once you've installed Node.js (npm) and Angular CLI onto your computer. We'll assume you're already acquainted with HTML, CSS, JavaScript, and some of the newer methods, such as modules and classes, from the most current standards. TypeScript is used to write the code samples. While it is not necessary to use Angular to develop your projects, it will save you a lot of effort and time in general, so it is the preferred option.

Rajesh

Rajesh Bhagia

Blog Author

Rajesh Bhagia is experienced campaigner in Lamp technologies and has 10 years of experience in Project Management. He has worked in Multinational companies and has handled small to very complex projects single-handedly. He started his career as Junior Programmer and has evolved in different positions including Project Manager of Projects in E-commerce Portals. Currently, he is handling one of the largest project in E-commerce Domain in MNC company which deals in nearly 9.5 million SKU's.

In his role as Project Manager at MNC company, Rajesh fosters an environment of teamwork and ensures that strategy is clearly defined while overseeing performance and maintaining morale. His strong communication and client service skills enhance his process-driven management philosophy.

Rajesh is a certified Zend Professional and has developed a flair for implementing PMP Knowledge Areas in daily work schedules. He has well understood the importance of these process and considers that using the knowledge Areas efficiently and correctly can turn projects to success. He also writes articles/blogs on Technology and Management

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How to Install Node.JS on a Mac

Node.js is an opensource JavaScript platform for general-purpose programming that allows users to quickly build network applications. As it uses JavaScript on both the front and backend, development becomes far more consistent and integrated. Node.js runs on various platforms (Windows, Linux, Unix, Mac OS, etc.) In this tutorial, we will discuss about Node.js installation on macOS.As we have already mentioned, Node.js allows you to write JavaScript on the server-side.  JavaScript, as you know, is a browser-based language. The creator of Node.js took the engine of Chrome and set it to work on a server. The browser's engine compiles JavaScript code into commands, and the language can be interpreted in an environment.   Npm is the platform for Node.js package management. It offers a tool for Node.js libraries to be installed, and their versions and dependencies managed.PrerequisitesHardware Requirement:RAM: 4 GB Storage: 256 GB of Hard Disk Space  Software Requirements:Web Browser: Any browser such as Google Chrome, Mozilla Firefox, Microsoft Edge, Safari.XCode: XCode software is used by Apple in building Mac and iOS applications, so it provides the instruments you need to compile Mac software. You can find XCode in the Apple App Store.  Homebrew: Homebrew is a package manager for the Mac. It readily allows the installation of most open-source software (like Node).  On the Homebrew website, you can find out more about Homebrew.Operating System: macOSInstallation ProcedureIn this article, we are going to look at three different ways to install Node.js on macOS.using the macOS installer  using homebrew  using Node Version ManagerSo, let us start.1. Using the macOS installerStep 1: Visit the Node.js website to update your Mac platform with the built installer.Node.js updates comprise two types, long-term support (LTS) and new releases. LTS versions are refined and bug-free, and are sufficient for most daily users. Current versions (Latest LTS 14.16.1) are more experimental and include the new functionality, which cannot be completed or crashed from time to time. By highlighting the field on the first tab, you can move between LTS and current versions. Again, most users use the LTS version. Therefore, you can just click on macOS installer, which will download the Node.js installer, if the LTS tab is highlighted in dark green.Step 2: Download .pkg installer and open the downloaded file with default installer.Step 3: After running the .pkg installer, follow the instructions on the interface.1. Introduction window: select Continue2. Licence window: Select Continue and a pop-up window will ask you to agree or disagree. 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The latest version of Node.js can be installed using Homebrew.Step 1: Use the following command to install Homebrew:s$ /usr/bin/ruby -e "$(curl -fsSL https://raw.githubusercontent.com/Homebrew/install/master/install)"When CURL downloads the script, the Ruby-interpreter starts the Homebrew installation process, which ships with macOS.During the operation, you will be asked to enter your password. While you don't see them, the machine records your keystrokes, so once your password has been entered, click the RETURN key.Step 2: Once homebrew is installed, use the following command to install Node.js:$ brew update $ brew install nodeStep 3: Verify the installation and check the version of Node.js and npm.$ node -v $ npm -vHomebrew always installs only the latest version of Node.js. This may be problematic since a certain version of Node.js might be required to function in applications. It can be a good thing to have the freedom to use those versions. The easiest way to solve this problem is by using NVM, the Node Version Manager.Using nvm to install and update Node.jsNVM is a bash script for several active versions of Node.js. Follow these steps to install Node.js:Step 1: The script copies the nvm-repository to ~/.nvm and then attaches the sources to the profile of the shell: ~/.bash profile, ~/.zshrc and ~/.profile or ~/.bashrc. Depending on what you have on your machine you can use curlUse the following command:$ curl -o- https://raw.githubusercontent.com/nvm-sh/nvm/v0.35.3/install.sh | bashStep 2:  Add the source lines in your shell profile. You can use ~/.bash_profile, ~/.zshrc, ~/.profile, or ~/.bashrc. In this article, we will be using zsh shell:$ vim .zshrcStep 3: Paste the following lines of code:export NVM_DIR="$HOME/.nvm"[ -s "$NVM_DIR/nvm.sh" ] && \. "$NVM_DIR/nvm.sh" [ -s "$NVM_DIR/bash_completion" ] && \. "\$NVM_DIR/bash_completion"Close the file by using esc + w + qStep 4: Use the following command to reload the shell:$ source ~/.zshrcStep 5: You can verify the installation with the following command and if the screen shown had nvm written as the output, then the installation is successful.$ command -v nvmNote: You can check the various commands of nvm with the following command:$ nvm + tab keyStep 6: Install LTS version:$ nvm install –ltsStep 7: Install the latest version of node:$ nvm install nodeThis is an alias for the latest version.Step 8: You can list out all the installed Node.js versions available on your system:$ nvm listStep 9: Install NPM:$ nvm install-latest -npmStep 10: This installs the latest NPM. After you've set up NPM, you can try out a number of useful commands:List and update globally installed packages:$ npm ls -g  --depth=0 $ npm update  -gCreate a simple ProgramLet's create a simple program "Hello, world." 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How to Install MongoDB on a Mac

MongoDB is one of the most popular unstructured database management systems that can store a high volume of data. It is a document-oriented database system that belongs to the family of NoSQL (non-SQL). Here the data and records are stored as documents that behave more like JSON objects. Documents are a combination of key-value pairs that form the basic unit of data in MongoDB. This database system came into action in mid-2000.What is NoSQL and why should we use NoSQL?NoSQL stands for Not Only SQL or non-SQL and is an unstructured database that helps store and retrieve data. In the year 1998, Carl Strozz introduced NoSQL. It models the data by means other than the tabular relations. It means such databases do not have a fixed schema, but are intended explicitly for the distributed data that demands humongous data storage. 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You can install Homebrew using the documentation given on their official website (https://brew.sh/#install).  Hardware Requirement:Intel Processor / Apple M1 Processor 4 GB RAM preferred Installation StepsInstall Manually without BrewStep 1: Let us now download MongoDB. For this, open your web browser and type: google.comStep 2: From Google search, type: MongoDB and hopefully, the first link the search throws up would be the MongoDB link. From here, we have two ways of installing MongoDB. Follow these steps to install using the macOS terminal.Step 3: Go to mongodb-community Select the version, platform, and package. Make sure you choose macOS as the platform and 'tgz' as the file format and click the download button.Step 4: Once the tgz file gets downloaded, go to the macOS terminal to extract it. Step 5: Mostly, your MongoDB will get downloaded in the Downloads folder. For this, type the following command in the terminal:cd Downloads/ ls tar xzf mongodb-osx-ssl-x86_64-4.4.tgz Step 6: Now, we have to move the MongoDB folder to our local binary storage. sudo mv mongodb-osx-ssl-x86_64-4.4 /usr/local/mongodbThis will ask for your system password. Provide the password. You can change the directory to /usr/local/mongodb and see whether all the files exist or not using the ls command. Note that this step is optional. To change the directory, type the command cd /usr/local/mongodb Next, you have to create the db folder. By default, MongoDB writes or stores the data in the folder called data/db. The command for this will be sudo mkdir -p /data/db The -p flag will allow us to create the directory structure. Now, to check whether this path and directory have been created or not, we use the command: cd /data/dbTo check whether we are on the right directory or not, just type the command: pwdFor changing the permission, you need to know your username first. 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If you haven't downloaded or installed Homebrew, then click the link (https://github.com/mongodb/homebrew-brew) to download the official Homebrew formula for MongoDB, by running the command in your macOS Terminal:  brew update  brew tap mongodb/brew Step 2: Once the Homebrew package resides in your system, you can download MongoDB using brew. Step 3: Type the following command in your macOS Terminal: brew install mongodb-community@version-numberStep 4: This installation will add the following binaries: The mongod server The mongo shell The mongos sharded cluster query router Step 5: The installation will take a few seconds. Once done, you can create a directory to store MongoDB data using the following command. sudo mkdir -p /data/db Step 6: Now, you have to note that your data directory should have the appropriate permissions. 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You can learn more about MongoDB installation and join the course from https://www.knowledgehut.com/web-development/mongodb-administrator.
How to Install MongoDB on a Mac

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How to Install Node.JS on Ubuntu

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Use curl to retrieve the installation script in your favourite version from your home directory so that your favourite version (if different) replaces 10.x:$ cd ~ $ curl -sL https://deb.nodesource.com/setup_10.x -o nodesource_setup.shStep 3: nano (or your preferred text editor) can be used to inspect the contents of this script:$ nano nodesource_setup.shStep 4: Now, run the script under sudo:$ sudo bash nodesource_setup.shStep 5: You add the PPA to the settings and automatically update your local package cache. You can install the Node.js package in the same way that you did above after running the Nodesource setup script:$ sudo apt install nodejsStep 6: To check the version of Node.js, use:$ nodejs -vThe nodejs package includes the nodejs binary and npm so that you don't have to install npm individually.Step 7: Npm uses a setup file to keep track of updates in your home directory. The first time you run npm, it will be created. 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Note that the version number may differ from the above:$ curl -sL https://raw.githubusercontent.com/creationix/nvm/v0.35.3/install.sh -o install_nvm.shStep 2: Use nano to inspect the installation script:$ nano install_nvm.shStep 3: Now, run the script with bash:$ bash install_nvm.shIt installs the software in your home ~/.nvm subdirectory. The lines needed to use the file will also be added into your ~/.profile.Step 4: You will either need to log out and log in back in to get access to NVM functionality or to source the ~/.profile file so you know the changes in the current session:$ source ~/.profileStep 5: You can install isolated versions of Node.js with nvm installed. For information on the available Node.js versions, type:$ nvm ls-remoteStep 6: As you can see, at the time of writing this blog, the current version of LTS was v12.18.3. You can install this with:$ nvm install 12.18.3Step 7: Normally, nvm will use the most recently installed version. You can instruct nvm to use the newly downloaded version by typing:$ nvm use 12.18.3Step 8: The executable is called node when you install Node.js with nvm. The current version of the shell can be seen by:$ node -vStep 9: You can see what is installed in your system if you have multiple Node.js versions:$ nvm lsStep 10: If you wish to default to any of the versions, use:$ nvm alias default 12.18.3Step 11: When a new session spawns, this version is automatically selected. You can also mention it through the alias as follows:$ nvm use defaultEach Node.js version will track and have npm available to manage its own packages.Step 12: In the directory of Node.js project's /node modules you can also have npm install packages. Install the express module using the following syntax:$ npm install expressStep 13: If you want the module to be installed globally by other projects with the same node.js version, you can add the flag -g:$ npm install -g expressThe package will install in:~/.nvm/versions/node/12.18.3/lib/node_modules/expressStep 14: If you install the module globally, you can execute commands from the command line, but the package must be linked to your local area in order to access this from a program:$ npm link expressStep 15: You can learn more about the nvm by using:$ nvm helpCreate Demo Web ServerStep 1: If your node is to be tested. Set up js. Let's build a "Hello World!" web server. You can use the following command to create a file app.js and open it in a text editor.Step 2: Set up a JavaScript (js) file to test the node. Let's build a "Hello World!" web server. You can use the following command to create a file app.js and open it in a text editor.$ gedit app.jsStep 3: Now, add the following content in the text editor and save it:var express = require('express'); var app = express();app.get('/', function (req, res) {   res.send('Hello World!'); });app.listen(3000, function () {   console.log('Example app listening on port 3000!'); });Step 4: Start the node application using the following command:$ node app.jsYou will see the output as an example app running in port 3000!Step 5: On port 3000 the webserver was launched. Here is a web browser access http://127.0.0.1:3000/ URL. Now you need to set up your app's front-end server.You're done, that's it. You have created your first Node application successfully. Don't stop here, continue to explore the beautiful Node.js world, as it has more to offer.How to Uninstall Node.js?Depending on the version you want to target, you can uninstall Node.js with apt or nvm. You have to work with the apt utility at system level in order to remove the distro-stable version.1. Using apt:$ sudo apt remove nodejsThis command will remove the package and keep the setup files. This can be useful for you if the package is to be reinstalled later.2. If the configuration files for future use are not to be saved, then run the following:$ sudo apt purge nodejsThis deactivates the package and deletes its associated configuration files.3. You can then delete any unused packages, which have been installed automatically with the deleted package:$ sudo apt autoremoveUninstall using NVM1. To uninstall a Node.js version that you have enabled with nvm, first determine whether the version you want to remove is the current active version:$ nvm current2. If the current active version is the version you want to remove, you must first deactivate NVM in order to allow your changes:$ nvm deactivateYou can uninstall the current version by using the command above to uninstall all the associated Node.js files with the exception of cached files which can be reinstalled.Learn more about the core concepts of Node with REPL, Cluster, Routing, Express with Node.js Certification Course.Conclusion:On your Ubuntu 18.04 server, there are a few ways to run Node.js. You can decide which of the above-mentioned methods are best suited to your needs. The easiest way to use the packaged version in Ubuntu's repository is by adding flexibility using nvm.
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How to Install Node.JS on Ubuntu

Node.js is a general-purpose programming JavaScrip... Read More