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Introduction to Hooks in React

Technological change is rapidly impacting our present and our prospects for the future, and so are frontend frameworks, which are emerging at a very fast pace these days. And in many ways, React, the most popular framework amongst the JavaScript community, is turning out to be unstoppable.   Many of us have already played around with Hooks or have at least heard about them. But there are still many who are probably yet to take the time or have had the chance to experiment with them.  No worries, sooner or later you will find yourself diving into Hooks.  In this article, you will learn about the term, ‘Hooks’, and the reasons why you should use them in your future projects. Furthermore, you will learn about how you can use React Hooks in the best possible manner to build some awesome features in your projects and write cleaner code.  What exactly is a Hook? Hooks are just regular JavaScript functions. In layman terms, hooks provide a way to use functionalities such as context or state, which could earlier only be achieved through classes, and now can easily be done using function components. React Hooks enable functional components to attach local state with it, and this state will be preserved by React when the component re-renders. Hence, this allows React to be used without classes. While working with function components in React, we sometimes need to add state to it. In order to achieve that (to use setState() and states), we have to convert our function component into class one. With the help of Hooks, we can use the state in Function Components, without the use of classes. A practical view There are two approaches to create a React component. One is using functions and the other is using classes. There is always a question in mind that “When do I use one v/s the other?” Let us assume we have a simple class component and then we will convert it to a functional one with hooks and see the difference. Component without Hook: Class Componentimport React, { Component } from'react';  classGreetingextendsComponent {     state = {         text: ''”     }  handleChange= (e) => {  this.setState({ text: e.target.value })     }  render() {  return (             <input  value={this.state.text}  onChange={this.handleChange}             />         )     }  }  exportdefaultGreeting; Components with Hook:Functional Component: import React, { useState } from'react';  exportdefault () => {  const [text, setText] =useState('');  return (         <input  value={text}  onChange={(e) =>{ setText(e.target.value) }}         />     );  }Advantages: Readable Lesser Code. Overall Optimized component Writing a Functional component with state Writing complex components became easier Handling events & logics in functional components. Performance boost up with Functional Components  If you disagree with any of the above, you can play with it in practice. I’m sure that would change your mind! Types of Hooks Now, let us understand the power of hooks with some cool examples that will describe some basic Hooks which are: useState() useEffect() Custom Hooks (Building Your Own Hooks) State Hook In React, we all are quite familiar with how the state is generally defined. If not, I’d recommend you to refresh your memory of State here. this.state= {     name: Steve Marley  }; While state issimilar to props, we know that state is controlled by a component. Traditionally, state is generally defined by writing a class where “this.state” is used to initialize a class. Let us take an example of class Component named (MyComponent): classMyComponentextendsReact.component {  constructor(props)  super(props);  this.state= {         name: Steve Marley     }  } In class components, it isreally hard to reuse stateful logic between components and complex class components become hard to read and even harder to understand!! React hooks help us to get rid of all that old-fashioned class stuff by making use of useState().  Now, this is important to note that in a functional component there is no concept of objects and objects being set as context (like we do in classes), so we can’t assign anything or read this.state. Instead, we call the useState Hook directly inside our functional component: This will become something like this: import{ useState } from'react'; // line 1  functionMyComponent() {  const [name, setName] =useState(‘Steve Marley');   // line 2  } Let us understand this code line by line: In line1: there is a new method imported here called useState. What is useState and how do we use it? Well, useState is the React Hook that will allow us to access and manipulate state in our existing component. Therefore, in this approach, we do not have to extend our Component as we did in previous code. And that’s it! It is worth noting that we are playing with states outside a class in the component directly as shown: import{ useState } from'react'; function MyComponent() { const [name, setName] =useState("Steve Marley"); return (<div>        <p>Heyyyyy!! {name}</p>    </div>) }Deeper explanation In class Component, we initialized the name state to 'Steve Marley' by setting this.state to { name: Steve Marley } in the constructor whereas in Functional componentthe only argument to the useState() Hook is the initial state.  Unlike with classes, the state does not have to be an object. We can keep a number or a string if that is all we need. What does useState return?It returns two variables in the array [name, setName]  where “name” is the state variable and it could be anything, and setName is the function call (can be named anything), which updates the state by providing a new state. If you are not familiar with the above syntax, please read array destructuring in JavaScript. In our example we have declared a state variable called name and set it to Steve Marley. React will remember its current value between re-renders and provide the most recent one to our function. If we want to update the current name, we can call setName. This is a way to “preserve” some values between the function calls so in other words useState is a new way to use the exact same capabilities that this.state provides in a class. Normally, variables “disappear” when the function exits but state variables are preserved by React. It is worth noticing that now our component (functional component) looks pretty simple, crisp and it does not have the level of complexity that a class component normally has. Effect Hook So far, we have seen extracting stateful logic with the help of hooks and defining/setting states inside a component. But what about managing the DOM from one component to another? Or fetching the data through an API? Or handling Events? All these operations which are quite familiar to usare effects!  The Effect Hook adds the ability to perform side effects from a functional component. It is a lifecycle Hook that combinescomponentDidMount, componentDidUpdate, and componentWillUnmount in React classes but unified them into a single API. useEffect(() => {  // Do some task here  }); By calling this hook, we are simply telling our component to perform some tasks after render like Data fetching, setting up a subscription, and manually changing the DOM in our React components. Let us understand this with an example: import React, { useState, useEffect } from"react"; exportdefaultfunctionGetData() {  const [myData, setData] =useState([]);  useEffect(() => {  fetch("https://jsonplaceholder.typicode.com/todos/1")  .then(response=>response.json())  .then(myData=>setData(myData));     });  retu

Introduction to Hooks in React

101
Introduction to Hooks in React



Technological change is rapidly impacting our present and our prospects for the future, and so are frontend frameworks, which are emerging at a very fast pace these days. And in many ways, React, the most popular framework amongst the JavaScript community, is turning out to be unstoppable.   

Many of us have already played around with Hooks or have at least heard about them. But there are still many who are probably yet to take the time or have had the chance to experiment with them.  No worries, sooner or later you will find yourself diving into Hooks.  

In this article, you will learn about the term, Hooks, and the reasons why you should use them in your future projects. Furthermore, you will learn about how you can use React Hooks in the best possible manner to build some awesome features in your projects and write cleaner code.  

Hooks in React

What exactly is a Hook? 

Hooks are just regular JavaScript functions. In layman terms, hooks provide a way to use functionalities such as context or state, which could earlier only be achieved through classes, and now can easily be done using function components. 

React Hooks enable functional components to attach local state with it, and this state will be preserved by React when the component re-renders. Hence, this allows React to be used without classes. 

While working with function components in React, we sometimes need to add state to it. In order to achieve that (to use setState() and states), we have to convert our function component into class one. With the help of Hooks, we can use the state in Function Components, without the use of classes. 

A practical view 

There are two approaches to create a React component. One is using functions and the other is using classes. There is always a question in mind that “When do I use one v/s the other?” 

Let us assume we have a simple class component and then we will convert it to a functional one with hooks and see the difference. 

Component without Hook: Class Component

import React, { Component } from'react'; 
classGreetingextendsComponent { 
   state = { 
       text: ''” 
   } 
handleChange= (e) => { 
this.setState({ text: e.target.value }) 
   } 
render() { 
return ( 
           <input 
value={this.state.text} 
onChange={this.handleChange} 
           /> 
       ) 
   } 
} 
exportdefaultGreeting; 

Components with Hook:Functional Component: 

import React, { useState } from'react'; 
exportdefault () => { 
const [text, setText] =useState(''); 
return ( 
       <input 
value={text} 
onChange={(e) =>{ setText(e.target.value) }} 
       /> 
   ); 
}

Advantages: 

  • Readable 
  • Lesser Code. 
  • Overall Optimized component 
  • Writing a Functional component with state 
  • Writing complex components became easier 
  • Handling events & logics in functional components. 
  • Performance boost up with Functional Components  

If you disagree with any of the above, you can play with it in practice. I’m sure that would change your mind! 

Types of Hooks 

Now, let us understand the power of hooks with some cool examples that will describe some basic Hooks which are: 

  • useState() 
  • useEffect() 
  • Custom Hooks (Building Your Own Hooks) 

State Hook 

In React, we all are quite familiar with how the state is generally defined. If not, I’d recommend you to refresh your memory of State here. 

this.state= { 
   name: Steve Marley 
}; 

While state issimilar to props, we know that state is controlled by a component. Traditionally, state is generally defined by writing a class where “this.state” is used to initialize a class. 

Let us take an example of class Component named (MyComponent): 

classMyComponentextendsReact.component { 
constructor(props) 
super(props); 
this.state= { 
       name: Steve Marley 
   } 
} 

In class components, it isreally hard to reuse stateful logic between components and complex class components become hard to read and even harder to understand!! 

React hooks help us to get rid of all that old-fashioned class stuff by making use of useState().  

Now, this is important to note that in a functional component there is no concept of objects and objects being set as context (like we do in classes), so we can’t assign anything or read this.state. Instead, we call the useState Hook directly inside our functional component: 

This will become something like this: 

import{ useState } from'react'; // line 1 
functionMyComponent() { 
const [name, setName] =useState(‘Steve Marley');   // line 2 
} 

Let us understand this code line by line: 

In line1: there is a new method imported here called useState. 

What is useState and how do we use it? 

Well, useState is the React Hook that will allow us to access and manipulate state in our existing component. Therefore, in this approach, we do not have to extend our Component as we did in previous code. 

And that’s it! It is worth noting that we are playing with states outside a class in the component directly as shown: 

import{ useState } from'react';
function MyComponent() { 
const [name, setName] =useState("Steve Marley"); 
return (<div> 
       <p>Heyyyyy!! {name}</p> 
   </div>)
}

Deeper explanation 

In class Component, we initialized the name state to 'Steve Marley' by setting this.state to { name: Steve Marley } in the constructor whereas in Functional componentthe only argument to the useState() Hook is the initial state.  

Unlike with classes, the state does not have to be an object. We can keep a number or a string if that is all we need. 

What does useState return?

It returns two variables in the array [name, setName]  

where “name” is the state variable and it could be anything, and setName is the function call (can be named anything), which updates the state by providing a new state. 

If you are not familiar with the above syntax, please read array destructuring in JavaScript. 

In our example we have declared a state variable called name and set it to Steve Marley. React will remember its current value between re-renders and provide the most recent one to our function. If we want to update the current name, we can call setName. 

This is a way to “preserve” some values between the function calls so in other words useState is a new way to use the exact same capabilities that this.state provides in a class. Normally, variables “disappear” when the function exits but state variables are preserved by React. 

It is worth noticing that now our component (functional component) looks pretty simple, crisp and it does not have the level of complexity that a class component normally has. 

Effect Hook 

So far, we have seen extracting stateful logic with the help of hooks and defining/setting states inside a component. But what about managing the DOM from one component to another? Or fetching the data through an API? Or handling Events? All these operations which are quite familiar to usare effects!  

The Effect Hook adds the ability to perform side effects from a functional component. It is a lifecycle Hook that combinescomponentDidMount, componentDidUpdate, and componentWillUnmount in React classes but unified them into a single API. 

useEffect(() => { 
// Do some task here 
}); 

By calling this hook, we are simply telling our component to perform some tasks after render like Data fetching, setting up a subscription, and manually changing the DOM in our React components. 

Let us understand this with an example: 

import React, { useState, useEffect } from"react";
exportdefaultfunctionGetData() { 
const [myData, setData] =useState([]); 
useEffect(() => { 
fetch("https://jsonplaceholder.typicode.com/todos/1") 
.then(response=>response.json()) 
.then(myData=>setData(myData)); 
   }); 
retu
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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.  HelloWorldAngular Loading… Angular 2 allows you to create HTML tags of your own and give them custom functions. These will then be called 'components.' 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. (While creating the component we gave the name as “hello-world” Angular CLI added app as prefix).3.TemplateUrl component in Angular 7 tag uses hello-world.component.html file as html template. We hereby then use 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:` hello-world works! `, 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. hello-world works! {{name}} 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.
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How to Install Angular CLI

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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. We use NoSQL databases for real-time web apps, mobile apps, big data, etc. Websites like Google, Twitter, Amazon, Facebook, Instagram, etc., collect terabytes of data every day.Earlier, web applications were simple and did not generate such huge amounts of data. But with the advent of big companies like Facebook, Google, Amazon, etc., huge volumes of data are generated, because of which NoSQL databases have become popular. Traditional RDBMS (like SQL) uses simple queries to store and retrieve textual data. But NoSQL database management systems embrace a wide range of file systems storing structured, unstructured, semi-structured, and polymorphic data.Features of NoSQLNoSQL databases do not follow the relational model. They are schema-free, or they do not follow any specific schema. NoSQL renders heterogeneous data structures (graph, tree, column family, key-value pair, document, etc.) on the same domain. Data is not stored flat in rows and columns (table). NoSQL does not demand data normalization and object-relational mapping. NoSQL does not demand setting up complex concepts like joins, referential integrity, ACID properties, etc. Who should use MongoDB?Developers who want to deal with structured, semi-structured, or unstructured data need to use MongoDB for their applications. Those who are into Big data analysis can also use MongoDB. Again, if an application's data needs agility, scaling, and high performance, MongoDB is the best solution.   It supports a broad spectrum of use cases, from real-time exploratory and predictive analytics to parallel data processing. MongoDB can provide high-performance data storage even when spread across multiple servers.PrerequisitesSoftware Requirement:macOS 10.13 or later MongoDB 4.4 Community Edition (we will show the download procedure later) Install Xcode Command-Line Tools: Homebrew demands to install the Xcode command-line tool from Apple's Xcode before using it. To install Xcode, you have to run the following command in your macOS Terminal:  xcode-select --install Homebrew package manager: By default, macOS does not incorporate the Homebrew package. 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. To know your username, type the command: whoamiNow change the permission of this directory. To do this, the command is: sudo chown /data/db Finally, you are eligible to directly run the mongo process.  Install using Brew –If you want to install MongoDB through Homebrew manually, follow these steps – Step 1: Homebrew helps in installing and managing applications on MacOS. 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. To do this, execute the command: sudo chown -R `id -un` /data/db Step 7: This will ensure that the data directory is ready and has all the proper permissions. Step 8: Apart from that, the MongoDB installation will produce the following files and directories at the locations given below – Intel Processors Apple M1  Log directory/usr/local/var/log/mongodb/opt/homebrew/var/log/mongodbConfiguration file/usr/local/etc/mongod.conf/opt/homebrew/etc/mongod.confData directory/usr/local/var/mongodb/opt/homebrew/var/mongodbStep 9: Let us now run the MongoDB community Edition. You can use the brew command to run MongoDB as a macOS. A manual procedure is needed to run MongoDB services on macOS. To execute MongoDB daemon, which resides by the name mongod (process), use the following command: brew services start mongodb-community macOS will run this process as a macOS service. Step 10: For stopping a mongod process running as a macOS service, apply the following command: brew services stop mongodb-communityStep 11: For running MongoDB in the background manually and listening for connections on a given port, use the following command - For Mac systems with Intel processors: mongod --config /usr/local/etc/mongod.conf --fork For Mac systems with Apple M1 processors: mongod --config /opt/homebrew/etc/mongod.conf –fork Step 12: Next, verify your MongoDB version. To do this, type the following command: mongo –version Step 13: The command line will display the installed version of MongoDB on your Mac system. Developers recommend using the newest version of libraries and software whenever feasible. It will keep you away from any compatibility issues with client-side applications. Step14: You can view the installation list by typing the command: mongodb Step15: Use the command mongod --config /usr/local/etc/mongod.conf to start the MongoDB Step 16: To connect to mongodb service, type the command: mongo Step17: Use the ‘show dbs’ command to see all databases. You can learn more about the working of MongoDB and become an expert NoSQL database administrator by joining the course https://www.knowledgehut.com/web-development/mongodb-administrator. This course covers features of MongoDB 4.0 and future releases. Uninstall MongoDB on macOS X –Uninstalling MongoDB from your system will entirely remove MongoDB along with its associated files. Before uninstalling MongoDB, check whether any mongo service is running by using the command: launchctl list | grep mongo If any running process exists before uninstallation, you should stop or kill it. To kill all the processes related to mongod, use the command: pkill -f mongod The command to uninstall MongoDB from your system is: If installed via brew: brew uninstall mongodb-communityOr, if installed manually you can simply delete the folder: rm -rf If you have a separate folder for the database, use the command to remove that database directory: rm -rf /data/db MongoDB is the leading NoSQL, document-based, open-source database system. It is a cross-platform system - licensed under the Server-Side Public License (SSPL). Due to its broad spectrum of features and benefits, it became popular very quickly. Hopefully, this article has helped you understand the basics of installing MongoDB in your Apple system.   In this article, we have walked you through the two ways to install MongoDB in a macOS. Also, this article explicitly talked about installing MongoDB in Apple systems with Intel processors and with Apple M1 processors. So, you can navigate this article as per your system. 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

MongoDB is one of the most popular unstructured da... Read More