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What is React Redux?

React is a JavaScript library for building user interfaces. One of the most popular UI libraries in use today, React is opensource and is maintained by Facebook. React has the best community support, with millions of developers who take part in discussions on best practices, React architecture, and the way forward with React.You can read more about React here.In this blog you are going to learn about React Redux. We can use it along with React for state management within the application.Prerequisites:This blog expects you to have good knowledge of JavaScript.You should have basic understanding of React, React Hooks and Components in React.Please ensure that the latest versions of npm and node are installed in your machine.To get started with React Redux, let’s first see what Redux is:What is Redux?Redux is a predictable state container for JavaScript apps, which means that Redux is predictable and it stores the state of your application. Redux will store and manage the application state.Redux itself is a standalone library that can be used with any UI layer or framework. Along with React, Redux can be used with many other JavaScript libraries and frameworks such as Angular, Vue and even with Vanilla JavaScript.You can read more about Redux here.When we are building a large-scale application, there is a need for a state management tool to avoid prop drilling all through the component. Redux is the most popular and widely used state management tool today.Note: Redux does what context api does in React. However, Redux was introduced before context api was introduced, and it continues to be the most popular state management library.In the next part of this article, you will learn to use Redux and in later parts you can learn how to integrate it with your React application.Learn Redux:Here you will understand the essential core concepts of Redux before learning how to use it with React.Start with creating an empty folder with the name Redux-Learnings in your desired location and open the folder in your favourite editor. VScode is preferred.Initially your project folder looks like this when it is opened in VScode:It should be empty. Let’s setup our project first.Now, let’s initialize a package.json file to store all our dependencies to learn Redux.Open integrated terminal for vscode and navigate to the project location.Next, run the below command in our terminal to initialize package.json in our project.Command: npm init –yesThere should be a package.json file inside the project as shown below.The next step is to install redux as a dependency for our project. Run the below command in the terminal to add redux as a dependency.Command: npm install reduxIf you check package.json file, you can see redux listed under the dependencies as shown below:Now create a file with the name index.js at the root level of the project and add a simple console statement to see the output on the terminal as shown below.Now, run the below command to run the index.js file.Command: node indexIt has to print the console statement to the terminal as shown below.Let’s start learning some theory behind Redux.Redux has 3 main components:StoreAction  ReducerWe will explain these components with the help of a real-world scenario.Imagine there is a restaurant, and you want to buy a meal. You will go to the restaurant and tell the retailer that you want to BUY a meal. The retailer takes out the meal from the bunch of meals with him, and gives it to you. You will then pay the money for the meal and get the receipt for the purchase. The receipt for the purchase is the proof that the number of meals has been decreased by one.Let’s see the 3 components in relation to the above scenario:Store: The store holds all the states of the application. This is similar to the restaurant holding all the meals.  Action: The Action here is to BUY_A_MEAL which describes what has happened. In this case you have bought a meal. The action describes changes in the state of the application.  Reducer: Reducers are similar to the retailer. They connect the store to the actions. In this case the retailer is decreasing the number of meals the restaurant (store) has. Reducers update the store according to the action.To put the 3 components of Redux into code, it’s important to learn the 3 main principles of Redux:The state of the whole application is stored in a single main object in the store. This means state is a single JavaScript object and lies inside the store. In our example, all the meals of the restaurant are to be represented in a single object. For example: { numberOfMeals: 10}The only way to change the state is to emit an Action. Emitting an action is the way of letting the Redux know what has happened. It’s an object describing what has happened. In our example BUY_A_MEAL is the action which is describing the action of buying a meal. You are NOT ALLOWED to update the state directly, but you always need an action to update the state.  Actions have types. For example: {type: “BUY_A_MEAL”}To specify how state changes based on actions, we use Reducers. A Reducer is a function that take initial state and action as inputs, and returns new state based on the type the action has. An example of a reducer for the above example is shown below. It decreases the number of meals in the restaurant (store).const reducer = (state, action) => { switch(action.type) { case BUY_A_MEAL: return { numberOfMeals: state.numberOfMeals-1 } } }Now let’s start coding our Redux app.As you have seen already, the 3 main components of redux are to be implemented in code. Let’s start with Actions.Creating Action:As you know that Actions are plain JavaScript objects and have ‘type’ property, which indicates the type of the actions being performed. You are not restricted to just having a type property;  instead, you can have additional properties as well.Also, in Redux we have action creator. As the name suggests, an action creator is a function which simply creates an action.Let’s go back to the project we have setup earlier and start coding Actions.  The Action Type and the Action Creator for our restaurant example can be written as shown below.Here BUY_A_MEAL is an action type and function buyMeal is an action creator, which returns an action which has type and the description in it.Creating Reducer:As we already know, a reducer is a function which takes in initial State and action, and returns a new state based on the type of action.The reducer can be created as shown below:Here the reducer is taking in the initial state and the action and returns the new state in the switch statement, where we compare the type in the case block and return the new state object.…state means that we are creating a copy of the state object and we are changing only the required properties.However, it's important to keep in mind that in redux we cannot change the state. Instead a new state is created with the changed properties and that is stored inside the Store.Creating Store:Before creating a store, its required to know the characteristics of Store:  Store holds the state of the application. Store provides a method called dispatch which allows updates to the application state. Dispatch method accepts an action as its parameter. Store allows components to access the state via getState() method. Registers listeners via subscribe method. That is the listener is called whenever the state is changed inside the store. Listener is a function which is passed to the subscribe method to call whenever the state changes. Unregister the listeners using the function returned by the subscribe method.Now let’s implement all the above in the code. If you see, we already have the state object by the name initialState in our code. Let’s create a store to hold our state using the redux package we installed earlier.As shown above, import Redux package using the required syntax. We need to make use of createStore method in Redux to create a store.Create a store by calling createStore method we pulled out from redux.createStore takes reducer as the parameter which has the application state.The store we created has the getState method which gives us the state of the application. To prove this, let’s add the console statement as shown below.If you run the file using node index command, you can see the console statement is printing the initial state to the console.  Now let’s quickly implement subscribe and dispatch methods as shown below.As mentioned earlier subscribe method takes a function as an argument. Here it’s a simple console statement which prints the state.  dispatch method takes in the action creator as an argument. I have just called it more times to trigger the state transitions more times.If you run the index file, you can see that the subscribe method is calling the listener function for every state change, and printing the new state as you can see above.  Now let’s unsubscribe to the listeners by calling the method returned by the subscribe method as shown below.Capture the unsubscribe method returned by the subscribe method, and call it in the middle to prove that we are unsubscribed to the state changes.If you can see above, listener has been called only 3 times for the 4 dispatch calls we made, as we unsubscribed before the 4th dispatch call.What is happening when we call dispatch method?When we call the dispatch method it dispatches an action buyMeal to the reducer which is returning the action which has a type BUY_A_MEAL. Now the reducer looks at the action type and compares with the case mentioned and returns the new state. As the state changes and the new state gets created in the store, the listener gets called and prints the new state to the console.This is the flow of redux. Going forward, do make sure that you understand and remember this flow.What if we have multiple actions?Let’s take the restaurant example again and say that we have snacks along with meals and we have different retailers(reducers) for each of these.  So, first step first, you need to update the initialState object to add the number of snacks and action type to buy a snack as shown below.Now let’s add an action creator to buy a snack (buySnack method).And also, a reducer case to handle buying a snack caseAnd also add some dispatch methods to dispatch buySnack action.Now if you run the index.js file and see the terminal output when buyMeal is dispatched, only the number of meals decreases, and when buySnack is dispatched only the number of snacks decreases.This method of using a single reducer works in this case. However, in a large-scale application, it gets hard to maintain and debug, also hard to keep track of the work flow.So, in many cases developers tend to create multiple reducers.  Create multiple reducers:For this you need to split the initial state of the application within index.js as shown belowHere, initialState object has been split into 2 state objects; one to store the number of Meals(initialMealState) and one to store the number of Snacks(initialSnackState).Similarly, we will split the reducer into 2 parts.Reducer related to Meals.Here, we have made mealReducer to handle actions related to Meals.Reducer related to Snacks.Here, we have made snackReducer to handle actions related to Snacks.If you observe by splitting the state and reducer, we are maintaining the centralized state and reducer functions for each component or feature in our application. By doing this it's always easy to maintain the code and to keep track of the workflow too.But if you look at the createStore method there is reducer passed in as an argument but now it no more exists. So, we need to combine the reducers before we pass it to createStore method.Combining Reducers:Combining reducers is very simple, and we can do this by using the combine reducers function which redux package offers.Extract combineReducers function from redux package as shown below:Now we need to combine all the reducers we have using the method we extracted above.The combineReducers function takes an object as a parameter which has all the reducers we have created as a key value pairs, and its generally called as rootReducer.We have to pass that rootReducer as an argument to the createStore method as shown in the above image.  Now if you run the file using node index you will see something like this inside the terminal.The meal and snack in the state object corresponds to the meal and snack keys we specified while combining the reducers.Now we have centralized state and reducers for each of our meals and snacks. We can add more actions to the existing reducers or even add new reducers. Also, it’s easy to maintain the code.This is the flow of the redux. We dispatch an action which has a type property to the reducer, and the reducer—based on the action type— updates the store accordingly.In real time applications, the actions are not synchronous as we have learnt above. We may have asynchronous actions, or we may want to add additional functionality to our redux workflow. For all of this we need to use middlewares.Middlewares:  Middlewares are the suggested way to extend redux functionality. Middlewares provide third party extension between dispatching an action and the moment the action reaches the reducer.Middlewares are normally used for logging, crash reporting or to perform some async tasks.  For example, we will now see how to add a middleware by using redux-logger middleware.  Read more about redux logger here.To install redux logger, go to vs code and run the following command in the terminal.Command: npm install redux-loggerNow if you go to the above-mentioned link for redux logger, you will find the code we write now.  We need to require the redux logger we just installed and create a logger as shown below.Now to apply this middleware, Redux has a function built into it which is called applyMiddleware.Extract applyMiddleware function from redux as shown below.Now pass the applyMiddleware as a second parameter to the createStore function as shown below.applyMiddleWare takes all the middlewares we have as arguments. In our case, it is logger.To see the middleware in action, remove the console.log statement inside the subscribe method of store and run the file using node index. You should see the outputs of the logger in the terminal as shown below.As mentioned above the actions used in the above example are synchronous actions but in real time applications the actions will be asynchronous.  As soon as we dispatch an action the state is updated in the above example. But in real time apps we may need to do an API call before we update the state. These types of actions are called asynchronous actions or async actions.Now let’s see how async actions are handled.Handling async actions:For this, let’s make an API call to fetch some users.So, let’s go to the same project we have been working with, for the above example, and create a new file asyncActions.js and work in this file.To implement redux, we need 3 things as we have learnt:StateActionsReducersLet’s look at each one of them.State:The state object looks like this:The loading key in the state object is set to false initially, and it is used to show a spinner when we are making an API call.The users key in the state object is initially set to an empty array, as we get an array of users after making the API call.The error key in the state object is initially set to an empty string as if the API call fails, we get the error string and we store the error message in this error key.Actions:  The action types and the action creators can be written as shown below.The fetchUsersLoading action creator can be used when the API call is in progress. So, this returns action type FETCH_USERS_LOADING.The fetchUsersSuccess action creator can be used when the API call is successful. We get an array of users as an argument for this function which returns the users array as a payload along with action type FETCH_USERS_SUCCESS.The fetchUsersFail action creator can be used when the API call fails, and we get an error message string as an argument for this function which returns the error message as a payload along with the action type FETCH_USERS_FAIL.Reducer:The reducer for the given scenario can be written as shown below.As mentioned already, FETCH_USERS_LOADING denotes that the API call is going on so loading should be set to true.FETCH_USERS_SUCCESS denotes that the API call is done and was successful. We can set loading to false again and users to action.payload as we are sending users inside payload in the action creator.FETCH_USERS_FAIL denotes that the API call is done and failed. We set loading to false again and error to action.payload as we are sending the error message inside payload in the action creator. Users is sent to an empty array as we will not get any users from the API.Now the last step remaining is to create the redux store.Create the store in the same way as the previous example.Now let’s see how to make an api call and actually handle async actions.To make an api call we use axios. You can read more about axios here.To define async action creators we use redux-thunk. It is a middleware that must be used in the same way that we used logger in the previous example.Read more about redux-thunk here.We need to install both the packages in order to use them. For that, open the terminal and run the following command.Command: npm install axios redux-thunkLet’s apply redux-thunk middleware as shown below. By requiring the redux-thunk and making use of applyMiddleWare in the same way as the previous example, we get:Now let’s write our async action creator which dispatches action creators which we have created earlier.We will make use of this API.First import axios as shown below.Next, make an API call for the above-mentioned end point using axios in our async action creator as shown below.Here fetchUsers is our async action creator and as we are using redux-thunk we can define async action creators. Redux-thunk allows us to return a function which has access to dispatch method through the arguments so that we can dispatch actions.We dispatch fetchUsersLoading initially as we are making an api call.Once the api call is successful we dispatch fetchUsersSuccess along with users as argument.If the API call fails, we dispatch fetchUsersFail along with the error message.  This is our async action creator which dispatches the necessary synchronous actions whenever required.Now write a subscribe method as shown in the above image and dispatch fetchUsers at the last.In the terminal, to run the file use the below command.Command: node asyncActions.jsYou can see the list of users in the terminal as shown below.Redux-thunk is widely used middleware to handle side effects such as API calls and other async tasks. It's important that you should learn about this package.And that’s it! You have completed learning about Redux concepts.Next, we move on to learning how to integrate Redux with your React application.  Before we start learning to integrate redux with react, let’s take a look at what react redux is.What is React Redux?React is a UI library whereas Redux is a state management library. They both work independently. We cannot use Redux directly in a react application, so we use React Redux to bind Redux in our React applications.React Redux is the official Redux UI binding library for React. If you are using Redux and React together, you should also use React Redux to bind these two libraries.This means if we want to use React and Redux together, we also need to use React Redux to bind them together.  For more information on React Redux, check this link.Installation:To directly create a redux app, run the following command inside the terminal.Command: npx create-react-app my-app --template reduxNavigate into the application using cd command and start making changes to the application.To integrate redux into an existing react project, run the following command inside the react project.Command: npm install redux react-reduxThis installs redux and react-redux packages to the React application and we can start integrating redux with react.We are going to follow the second method as we are going to integrate redux with the existing react application.Let’s try rebuilding the above example with a UI.We will start with the setup as shown below. This has been created using create-react-app and has been changed according to our needs.Folder structure:App.js:App.js has only one component called MealContainer.MealContainer.js:Now if you run the app using the npm start command you will see the similar UI in the browser.Now, let’s start with integrating redux with our react application.As mentioned above, install redux and redux-thunk by running the below command.Command: npm install redux react-reduxAfter the installation, create a new folder inside src with the name redux. All our redux logic goes into this folder. Now inside this, I would like to create folders with the feature names as all the logic related to a particular feature can be kept organized in a single place. As we have only one feature by the name meals, create a folder with the name meals and 2 files with the names mealActions.js and mealTypes.js to create the actions and action types for this particular feature as shown below.Inside the mealTypes.js export the action type as shown below.Note: export keyword is used so that we are able to use the particular function or object in other files by importing them using import key word.Create an action creator to buy a meal as we have learnt in the previous example.Now let’s create reducer for our meals feature. For this, create a new file with the name mealReducer.js inside the same folder and create reducer for the meals feature.Now let’s create the redux store. For this, create a file with the name store.js inside redux folder as store is common for all the features. Next, create a store as we have already learnt, and export it as the default.Now that we have set up our redux for the application, how does our application get access to the store? Well, for that we need to go to the react-redux package we installed; this is where react-redux makes its first appearance. We need to go to Provider which react-redux offers in order to make our app know about the store.Go to the app.js file and import Provider from react-redux, and wrap the whole app with this provider passing store as a prop to it.Now what remains is to connect redux to our components, dispatch an action and update the store from the components.Connecting redux to the components:As a first step, write a couple of functions mapStateToProps and mapDispatchToProps as shown below.mapStateToProps is a function that you would use to provide the store data to the component as prop. Whereas mapDispatchToProps is something that you will use to provide the action creators as props to the component.Read more about the 2 functions here.We import buyMeal action from the action file to use in mapDispatchToProps.Now to connect both the functions to the component, we need to import connect which react-redux offers us as shown below.Now using that, we connect the state and actions to the component as shown below.mapStateToProps and mapDispatchToProps are passed as arguments to the connect function.Now we can access the numOfMeals using the props object and show that in the UI.The numOfMeals upon the props pertains to the key returned by the object in the mapStateToProps.If you save and check the UI, you can see the number of meals displayed.Now let’s dispatch our buyMeals action. This is available on the props object, as we have used mapDispatchToProps. Upon the click of the button, we execute the function which dispatches our action as shown below.Now if you click the button in the UI, the meals should decrease by 1.Now, let’s integrate logic for the snacks as well.  Add SnackContainer.js file similar to mealContainer and add it in the App.js file as shown below.In the redux folder, add a new folder for snacks feature and add the necessary files in the same manner as the meals folder.snackTypes.jssnackActions.jsNext, write the reducer in the snackReducer.jsAs we have 2 reducers, we need to combine reducers as we have learnt previously, and pass the rootReducer to the store.Due to this change, the application will break as we have changed the structure of the state in the store. So, we need to make some changes in mealContainer as shown below.Let’s connect the state to the snackContainer component in the same way that we have done in the mealContainer component, as shown below.If you check the UI, you will be able to see the number of snacks displayed as shown below.If we click on the Buy Snacks button, that should decrease the number of snacks by 1.And that’s it! We have implemented React-Redux along with the React UI.Let’s see how to manage Async actions in UI.If you see, we have rewritten the same code we have used to learn Redux.Let’s implement the same API call example we have learnt above in React. We will consider that these are the users who are using our restaurant.  Async Actions along with React UI:  Install the necessary packages as shown below.Command: npm install axios redux-thunkCreate a user’s folder as we are adding user features to this application. In the user’s folder add usersTypes.js to add the types we have learnt in the async actions example we used while learning redux.Now let’s create the usersReducer in the same way that we have learnt.Add our async action creator as well.Now let’s create the usersReducer in the same way that we have learnt.Next, add our usersReducer to the combineReducers and configure redux-thunk middleware in store.js.And we are done with the redux-logic! Let’s add usersContainer.js file in the components folder, write the following code and add it to App.js.App.js now looks as shown below.Now let’s connect our state to the component as shown below.Now if you go to the UI and click the Load Users button, this should show up all the users names that we have fetched from the API.We are done!Reasons to use React Redux:It is the official Redux UI Binding for React.It encourages good React architecture.  It implements Performance Optimizations  It has great community support.Redux has its own drawbacks that need to be overcome. For this, Redux has come up with Redux-toolkit.An Introduction to Redux toolkit:The Redux Toolkit package is intended to be the standard way to write Redux logic. It was originally created to help address three common concerns about Redux:"Configuring a Redux store is too complicated""I have to add a lot of packages to get Redux to do anything useful""Redux requires too much boilerplate code"Read more about redux-toolkit here.Installation:To create a new React app, along with Redux toolkit run the below command.Command: npx create-react-app my-app --template reduxTo add the Redux toolkit to an already existing app:Command: npm install @reduxjs/toolkitOther Resources:Link to learn more about React Redux.To read more about the connect function we have used.Learn React.Summary:In this blog you have all the information you need to work with React-Redux. You have learnt how to implement Redux, and understood the use of actions, reducers, store, action creators, middlewares. You would have understood how to handle async actions, combine reducers, integrate redux to react UI, connect components and also the use of Redux toolkit.Good luck with your React-Redux learning journey!

What is React Redux?

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What is React Redux?

React is a JavaScript library for building user interfaces. One of the most popular UI libraries in use today, React is opensource and is maintained by Facebook. React has the best community support, with millions of developers who take part in discussions on best practices, React architecture, and the way forward with React.

You can read more about React here.

In this blog you are going to learn about React Redux. We can use it along with React for state management within the application.

Prerequisites:

  • This blog expects you to have good knowledge of JavaScript.
  • You should have basic understanding of React, React Hooks and Components in React.
  • Please ensure that the latest versions of npm and node are installed in your machine.

To get started with React Redux, let’s first see what Redux is:

What is Redux?

Redux is a predictable state container for JavaScript apps, which means that Redux is predictable and it stores the state of your application. Redux will store and manage the application state.

Redux itself is a standalone library that can be used with any UI layer or framework. Along with React, Redux can be used with many other JavaScript libraries and frameworks such as Angular, Vue and even with Vanilla JavaScript.

You can read more about Redux here.

When we are building a large-scale application, there is a need for a state management tool to avoid prop drilling all through the component. Redux is the most popular and widely used state management tool today.

Note: Redux does what context api does in React. However, Redux was introduced before context api was introduced, and it continues to be the most popular state management library.

In the next part of this article, you will learn to use Redux and in later parts you can learn how to integrate it with your React application.

Learn Redux:

Here you will understand the essential core concepts of Redux before learning how to use it with React.

Start with creating an empty folder with the name Redux-Learnings in your desired location and open the folder in your favourite editor. VScode is preferred.

Initially your project folder looks like this when it is opened in VScode:

It should be empty. Let’s setup our project first.

Now, let’s initialize a package.json file to store all our dependencies to learn Redux.

Open integrated terminal for vscode and navigate to the project location.

Next, run the below command in our terminal to initialize package.json in our project.

Command: npm init –yes

There should be a package.json file inside the project as shown below.

The next step is to install redux as a dependency for our project. Run the below command in the terminal to add redux as a dependency.

Command: npm install redux

If you check package.json file, you can see redux listed under the dependencies as shown below:

Now create a file with the name index.js at the root level of the project and add a simple console statement to see the output on the terminal as shown below.

Now, run the below command to run the index.js file.

Command: node index

It has to print the console statement to the terminal as shown below.

Let’s start learning some theory behind Redux.

Redux has 3 main components:

  1. Store
  2. Action  
  3. Reducer

We will explain these components with the help of a real-world scenario.

Imagine there is a restaurant, and you want to buy a meal. You will go to the restaurant and tell the retailer that you want to BUY a meal. The retailer takes out the meal from the bunch of meals with him, and gives it to you. You will then pay the money for the meal and get the receipt for the purchase. The receipt for the purchase is the proof that the number of meals has been decreased by one.

Let’s see the 3 components in relation to the above scenario:

  1. Store: The store holds all the states of the application. This is similar to the restaurant holding all the meals.  
  2. Action: The Action here is to BUY_A_MEAL which describes what has happened. In this case you have bought a meal. The action describes changes in the state of the application.  
  3. Reducer: Reducers are similar to the retailer. They connect the store to the actions. In this case the retailer is decreasing the number of meals the restaurant (store) has. Reducers update the store according to the action.

To put the 3 components of Redux into code, it’s important to learn the 3 main principles of Redux:

  1. The state of the whole application is stored in a single main object in the store. This means state is a single JavaScript object and lies inside the store. In our example, all the meals of the restaurant are to be represented in a single object. For example: { numberOfMeals: 10}
  2. The only way to change the state is to emit an Action. Emitting an action is the way of letting the Redux know what has happened. It’s an object describing what has happened. In our example BUY_A_MEAL is the action which is describing the action of buying a meal. You are NOT ALLOWED to update the state directly, but you always need an action to update the state.  
    Actions have types. For example: {type: “BUY_A_MEAL”}
  3. To specify how state changes based on actions, we use Reducers. A Reducer is a function that take initial state and action as inputs, and returns new state based on the type the action has. An example of a reducer for the above example is shown below. It decreases the number of meals in the restaurant (store).
const reducer = (state, action) => {
  switch(action.type) {
    case BUY_A_MEAL: 
      return {
        numberOfMeals: state.numberOfMeals-1
      }
  }
}

Now let’s start coding our Redux app.

As you have seen already, the 3 main components of redux are to be implemented in code. Let’s start with Actions.

Creating Action:
As you know that Actions are plain JavaScript objects and have ‘type’ property, which indicates the type of the actions being performed. You are not restricted to just having a type property;  instead, you can have additional properties as well.

Also, in Redux we have action creator. As the name suggests, an action creator is a function which simply creates an action.

Let’s go back to the project we have setup earlier and start coding Actions.  

The Action Type and the Action Creator for our restaurant example can be written as shown below.

Here BUY_A_MEAL is an action type and function buyMeal is an action creator, which returns an action which has type and the description in it.

Creating Reducer:

As we already know, a reducer is a function which takes in initial State and action, and returns a new state based on the type of action.

The reducer can be created as shown below:

Here the reducer is taking in the initial state and the action and returns the new state in the switch statement, where we compare the type in the case block and return the new state object.

…state means that we are creating a copy of the state object and we are changing only the required properties.

However, it's important to keep in mind that in redux we cannot change the state. Instead a new state is created with the changed properties and that is stored inside the Store.

Creating Store:

Before creating a store, its required to know the characteristics of Store:  

  • Store holds the state of the application. 
  • Store provides a method called dispatch which allows updates to the application state. Dispatch method accepts an action as its parameter. 
  • Store allows components to access the state via getState() method. 
  • Registers listeners via subscribe method. That is the listener is called whenever the state is changed inside the store. Listener is a function which is passed to the subscribe method to call whenever the state changes. 
  • Unregister the listeners using the function returned by the subscribe method.

Now let’s implement all the above in the code. 

If you see, we already have the state object by the name initialState in our code. Let’s create a store to hold our state using the redux package we installed earlier.

As shown above, import Redux package using the required syntax. We need to make use of createStore method in Redux to create a store.

Create a store by calling createStore method we pulled out from redux.

createStore takes reducer as the parameter which has the application state.

The store we created has the getState method which gives us the state of the application. To prove this, let’s add the console statement as shown below.

If you run the file using node index command, you can see the console statement is printing the initial state to the console.  

Now let’s quickly implement subscribe and dispatch methods as shown below.

As mentioned earlier subscribe method takes a function as an argument. Here it’s a simple console statement which prints the state.  

dispatch method takes in the action creator as an argument. I have just called it more times to trigger the state transitions more times.

If you run the index file, you can see that the subscribe method is calling the listener function for every state change, and printing the new state as you can see above.  

Now let’s unsubscribe to the listeners by calling the method returned by the subscribe method as shown below.

Capture the unsubscribe method returned by the subscribe method, and call it in the middle to prove that we are unsubscribed to the state changes.

If you can see above, listener has been called only 3 times for the 4 dispatch calls we made, as we unsubscribed before the 4th dispatch call.

What is happening when we call dispatch method?

When we call the dispatch method it dispatches an action buyMeal to the reducer which is returning the action which has a type BUY_A_MEAL. Now the reducer looks at the action type and compares with the case mentioned and returns the new state. As the state changes and the new state gets created in the store, the listener gets called and prints the new state to the console.

This is the flow of redux. Going forward, do make sure that you understand and remember this flow.

What if we have multiple actions?

Let’s take the restaurant example again and say that we have snacks along with meals and we have different retailers(reducers) for each of these.  

So, first step first, you need to update the initialState object to add the number of snacks and action type to buy a snack as shown below.

Now let’s add an action creator to buy a snack (buySnack method).

And also, a reducer case to handle buying a snack case

And also add some dispatch methods to dispatch buySnack action.

Now if you run the index.js file and see the terminal output when buyMeal is dispatched, only the number of meals decreases, and when buySnack is dispatched only the number of snacks decreases.

This method of using a single reducer works in this case. However, in a large-scale application, it gets hard to maintain and debug, also hard to keep track of the work flow.

So, in many cases developers tend to create multiple reducers.  

Create multiple reducers:

For this you need to split the initial state of the application within index.js as shown below

Here, initialState object has been split into 2 state objects; one to store the number of Meals(initialMealState) and one to store the number of Snacks(initialSnackState).

Similarly, we will split the reducer into 2 parts.

Reducer related to Meals.

Here, we have made mealReducer to handle actions related to Meals.

Reducer related to Snacks.

Here, we have made snackReducer to handle actions related to Snacks.

If you observe by splitting the state and reducer, we are maintaining the centralized state and reducer functions for each component or feature in our application. By doing this it's always easy to maintain the code and to keep track of the workflow too.

But if you look at the createStore method there is reducer passed in as an argument but now it no more exists. So, we need to combine the reducers before we pass it to createStore method.

Combining Reducers:

Combining reducers is very simple, and we can do this by using the combine reducers function which redux package offers.

Extract combineReducers function from redux package as shown below:

Now we need to combine all the reducers we have using the method we extracted above.

The combineReducers function takes an object as a parameter which has all the reducers we have created as a key value pairs, and its generally called as rootReducer.

We have to pass that rootReducer as an argument to the createStore method as shown in the above image.  

Now if you run the file using node index you will see something like this inside the terminal.

The meal and snack in the state object corresponds to the meal and snack keys we specified while combining the reducers.

Now we have centralized state and reducers for each of our meals and snacks. We can add more actions to the existing reducers or even add new reducers. Also, it’s easy to maintain the code.

This is the flow of the redux. We dispatch an action which has a type property to the reducer, and the reducer—based on the action type— updates the store accordingly.

In real time applications, the actions are not synchronous as we have learnt above. We may have asynchronous actions, or we may want to add additional functionality to our redux workflow. For all of this we need to use middlewares.

Middlewares:  

Middlewares are the suggested way to extend redux functionality. Middlewares provide third party extension between dispatching an action and the moment the action reaches the reducer.

Middlewares are normally used for logging, crash reporting or to perform some async tasks.  

For example, we will now see how to add a middleware by using redux-logger middleware.  

Read more about redux logger here.

To install redux logger, go to vs code and run the following command in the terminal.

Command: npm install redux-logger

Now if you go to the above-mentioned link for redux logger, you will find the code we write now.  

We need to require the redux logger we just installed and create a logger as shown below.

Now to apply this middleware, Redux has a function built into it which is called applyMiddleware.

Extract applyMiddleware function from redux as shown below.

Now pass the applyMiddleware as a second parameter to the createStore function as shown below.

applyMiddleWare takes all the middlewares we have as arguments. In our case, it is logger.

To see the middleware in action, remove the console.log statement inside the subscribe method of store and run the file using node index. You should see the outputs of the logger in the terminal as shown below.

As mentioned above the actions used in the above example are synchronous actions but in real time applications the actions will be asynchronous.  

As soon as we dispatch an action the state is updated in the above example. But in real time apps we may need to do an API call before we update the state. These types of actions are called asynchronous actions or async actions.

Now let’s see how async actions are handled.

Handling async actions:

For this, let’s make an API call to fetch some users.

So, let’s go to the same project we have been working with, for the above example, and create a new file asyncActions.js and work in this file.

To implement redux, we need 3 things as we have learnt:

  1. State
  2. Actions
  3. Reducers

Let’s look at each one of them.

State:

The state object looks like this:

The loading key in the state object is set to false initially, and it is used to show a spinner when we are making an API call.

The users key in the state object is initially set to an empty array, as we get an array of users after making the API call.

The error key in the state object is initially set to an empty string as if the API call fails, we get the error string and we store the error message in this error key.

Actions:  

The action types and the action creators can be written as shown below.

The fetchUsersLoading action creator can be used when the API call is in progress. So, this returns action type FETCH_USERS_LOADING.

The fetchUsersSuccess action creator can be used when the API call is successful. We get an array of users as an argument for this function which returns the users array as a payload along with action type FETCH_USERS_SUCCESS.

The fetchUsersFail action creator can be used when the API call fails, and we get an error message string as an argument for this function which returns the error message as a payload along with the action type FETCH_USERS_FAIL.

Reducer:

The reducer for the given scenario can be written as shown below.

As mentioned already, FETCH_USERS_LOADING denotes that the API call is going on so loading should be set to true.

FETCH_USERS_SUCCESS denotes that the API call is done and was successful. We can set loading to false again and users to action.payload as we are sending users inside payload in the action creator.

FETCH_USERS_FAIL denotes that the API call is done and failed. We set loading to false again and error to action.payload as we are sending the error message inside payload in the action creator. Users is sent to an empty array as we will not get any users from the API.

Now the last step remaining is to create the redux store.

Create the store in the same way as the previous example.

Now let’s see how to make an api call and actually handle async actions.

To make an api call we use axios. You can read more about axios here.

To define async action creators we use redux-thunk. It is a middleware that must be used in the same way that we used logger in the previous example.

Read more about redux-thunk here.

We need to install both the packages in order to use them. For that, open the terminal and run the following command.

Command: npm install axios redux-thunk

Let’s apply redux-thunk middleware as shown below. By requiring the redux-thunk and making use of applyMiddleWare in the same way as the previous example, we get:

Now let’s write our async action creator which dispatches action creators which we have created earlier.

We will make use of this API.

First import axios as shown below.

Next, make an API call for the above-mentioned end point using axios in our async action creator as shown below.

Here fetchUsers is our async action creator and as we are using redux-thunk we can define async action creators. Redux-thunk allows us to return a function which has access to dispatch method through the arguments so that we can dispatch actions.

We dispatch fetchUsersLoading initially as we are making an api call.

Once the api call is successful we dispatch fetchUsersSuccess along with users as argument.

If the API call fails, we dispatch fetchUsersFail along with the error message.  

This is our async action creator which dispatches the necessary synchronous actions whenever required.

Now write a subscribe method as shown in the above image and dispatch fetchUsers at the last.

In the terminal, to run the file use the below command.

Command: node asyncActions.js

You can see the list of users in the terminal as shown below.

Redux-thunk is widely used middleware to handle side effects such as API calls and other async tasks. It's important that you should learn about this package.

And that’s it! You have completed learning about Redux concepts.

Next, we move on to learning how to integrate Redux with your React application.  

Before we start learning to integrate redux with react, let’s take a look at what react redux is.

What is React Redux?

React is a UI library whereas Redux is a state management library. They both work independently. We cannot use Redux directly in a react application, so we use React Redux to bind Redux in our React applications.

React Redux is the official Redux UI binding library for React. If you are using Redux and React together, you should also use React Redux to bind these two libraries.

This means if we want to use React and Redux together, we also need to use React Redux to bind them together.  

For more information on React Redux, check this link.

Installation:

To directly create a redux app, run the following command inside the terminal.

Command: npx create-react-app my-app --template redux

Navigate into the application using cd command and start making changes to the application.

To integrate redux into an existing react project, run the following command inside the react project.

Command: npm install redux react-redux

This installs redux and react-redux packages to the React application and we can start integrating redux with react.

We are going to follow the second method as we are going to integrate redux with the existing react application.

Let’s try rebuilding the above example with a UI.

We will start with the setup as shown below. This has been created using create-react-app and has been changed according to our needs.

Folder structure:

App.js:

App.js has only one component called MealContainer.

MealContainer.js:

Now if you run the app using the npm start command you will see the similar UI in the browser.

Now, let’s start with integrating redux with our react application.

As mentioned above, install redux and redux-thunk by running the below command.

Command: npm install redux react-redux

After the installation, create a new folder inside src with the name redux. All our redux logic goes into this folder. Now inside this, I would like to create folders with the feature names as all the logic related to a particular feature can be kept organized in a single place. As we have only one feature by the name meals, create a folder with the name meals and 2 files with the names mealActions.js and mealTypes.js to create the actions and action types for this particular feature as shown below.

Inside the mealTypes.js export the action type as shown below.

Note: export keyword is used so that we are able to use the particular function or object in other files by importing them using import key word.

Create an action creator to buy a meal as we have learnt in the previous example.

Now let’s create reducer for our meals feature. For this, create a new file with the name mealReducer.js inside the same folder and create reducer for the meals feature.

Now let’s create the redux store. For this, create a file with the name store.js inside redux folder as store is common for all the features. Next, create a store as we have already learnt, and export it as the default.

Now that we have set up our redux for the application, how does our application get access to the store? Well, for that we need to go to the react-redux package we installed; this is where react-redux makes its first appearance. We need to go to Provider which react-redux offers in order to make our app know about the store.

Go to the app.js file and import Provider from react-redux, and wrap the whole app with this provider passing store as a prop to it.

Now what remains is to connect redux to our components, dispatch an action and update the store from the components.

Connecting redux to the components:

As a first step, write a couple of functions mapStateToProps and mapDispatchToProps as shown below.

mapStateToProps is a function that you would use to provide the store data to the component as prop. Whereas mapDispatchToProps is something that you will use to provide the action creators as props to the component.

Read more about the 2 functions here.

We import buyMeal action from the action file to use in mapDispatchToProps.

Now to connect both the functions to the component, we need to import connect which react-redux offers us as shown below.

Now using that, we connect the state and actions to the component as shown below.

mapStateToProps and mapDispatchToProps are passed as arguments to the connect function.

Now we can access the numOfMeals using the props object and show that in the UI.

The numOfMeals upon the props pertains to the key returned by the object in the mapStateToProps.

If you save and check the UI, you can see the number of meals displayed.

Now let’s dispatch our buyMeals action. This is available on the props object, as we have used mapDispatchToProps. Upon the click of the button, we execute the function which dispatches our action as shown below.

Now if you click the button in the UI, the meals should decrease by 1.

Now, let’s integrate logic for the snacks as well.  

Add SnackContainer.js file similar to mealContainer and add it in the App.js file as shown below.

In the redux folder, add a new folder for snacks feature and add the necessary files in the same manner as the meals folder.

snackTypes.js

snackActions.js

Next, write the reducer in the snackReducer.js

As we have 2 reducers, we need to combine reducers as we have learnt previously, and pass the rootReducer to the store.

Due to this change, the application will break as we have changed the structure of the state in the store. So, we need to make some changes in mealContainer as shown below.

Let’s connect the state to the snackContainer component in the same way that we have done in the mealContainer component, as shown below.

If you check the UI, you will be able to see the number of snacks displayed as shown below.

If we click on the Buy Snacks button, that should decrease the number of snacks by 1.

And that’s it! We have implemented React-Redux along with the React UI.

Let’s see how to manage Async actions in UI.

If you see, we have rewritten the same code we have used to learn Redux.

Let’s implement the same API call example we have learnt above in React. We will consider that these are the users who are using our restaurant.  

Async Actions along with React UI:  

Install the necessary packages as shown below.

Command: npm install axios redux-thunk

Create a user’s folder as we are adding user features to this application. In the user’s folder add usersTypes.js to add the types we have learnt in the async actions example we used while learning redux.

Now let’s create the usersReducer in the same way that we have learnt.

Add our async action creator as well.

Now let’s create the usersReducer in the same way that we have learnt.

Next, add our usersReducer to the combineReducers and configure redux-thunk middleware in store.js.

And we are done with the redux-logic! Let’s add usersContainer.js file in the components folder, write the following code and add it to App.js.

App.js now looks as shown below.

Now let’s connect our state to the component as shown below.

Now if you go to the UI and click the Load Users button, this should show up all the users names that we have fetched from the API.

We are done!

Reasons to use React Redux:

  • It is the official Redux UI Binding for React.
  • It encourages good React architecture.  
  • It implements Performance Optimizations  
  • It has great community support.

Redux has its own drawbacks that need to be overcome. For this, Redux has come up with Redux-toolkit.

An Introduction to Redux toolkit:

The Redux Toolkit package is intended to be the standard way to write Redux logic. It was originally created to help address three common concerns about Redux:

  • "Configuring a Redux store is too complicated"
  • "I have to add a lot of packages to get Redux to do anything useful"
  • "Redux requires too much boilerplate code"

Read more about redux-toolkit here.

Installation:

To create a new React app, along with Redux toolkit run the below command.

Command: npx create-react-app my-app --template redux

To add the Redux toolkit to an already existing app:

Command: npm install @reduxjs/toolkit

Other Resources:

Link to learn more about React Redux.

To read more about the connect function we have used.

Learn React.

Summary:

In this blog you have all the information you need to work with React-Redux. You have learnt how to implement Redux, and understood the use of actions, reducers, store, action creators, middlewares. You would have understood how to handle async actions, combine reducers, integrate redux to react UI, connect components and also the use of Redux toolkit.

Good luck with your React-Redux learning journey!

KnowledgeHut

KnowledgeHut

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KnowledgeHut is an outcome-focused global ed-tech company. We help organizations and professionals unlock excellence through skills development. We offer training solutions under the people and process, data science, full-stack development, cybersecurity, future technologies and digital transformation verticals.
Website : https://www.knowledgehut.com

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An example is Sass, which adds special features like variables and nested rules in CSS and is widely used in the industry for larger projects. The other popular one is PostCSS, in which we can use custom plugin and tools in CSS. CSS Frameworks  Frameworks were very popular from the early days of CSS, when it was very complicated because of floats. Bootstrap  This is the most popular and oldest CSS framework; easy to learn and also has a wide variety of elements, templates and interfaces. Bulma   It is another CSS framework, which is very popular and much easier to use than bootstrap. Tailwind CSS   This is a fairly new CSS framework and is quite popular nowadays. It follows a different approach than the other frameworks and contains easier classes. Styled Components (React)   This is a CSS in JS library and is for React only. It is used to create components out of every style and is very popular in the React world.  CI/CDThe Continuous Integration/ Continuous deployment is mainly used by DevOps. But a frontend engineer should know its basics. It is used to build, test and deploy applications automatically.Github Actions    It is a freely available CI/CD pipeline, which directly integrates to your github based project and can be used in a variety of languages. Deployment It is again a task which mainly falls into the domain of Backend engineers and DevOps, but a frontend engineer should know some basic and simple tools. Static Deployment   These products are mainly used to deploy static sites, which consists of HTML, CSS and JavaScript only. Two very popular services are Amazon S3 and Surge.sh Node Application Deployment   The projects containing node code cannot be deployed using static deployment. Even if the project is a simple ReactJS project, it also uses node for processing. These applications require services which run the Node code and deploy it. The three most popular services are Vercel, Firebase and Netlify. 2. Backend Roadmap (Including Storage, Services & Deployment)Understanding the BackendBackend is the part of the website that provides the functionality, allowing people to browse their favorite site, purchase a product and log into their account, for instance. All data related to a user or a product or anything else are generally stored in databases or CMS (Content Management System) and when a user visits any website, they are retrieved from there and shown. One of the responsibilities of a backend engineer involves writing APIs, which actually interact with the database and get the data. They are also involved in writing schemas of database and creating the structure of databases. Backend EssentialsFor a backend engineer, working in a Linux environment is an essential skill. A lot of the configurations are done on the terminal. So, he or she should be very good with Linux commands.Also, they should know both commands and the use of any git powered platforms like Github or bitbucket.Languages and FrameworksAll of the popular languages have some framework, which has been used for backend development. These frameworks are generally used to create API endpoints, which are used to fetch or store data in the database. For example, when we scroll articles on Facebook, these articles are fetched from a database and we use the GET method to fetch them. Similarly, when we write an article and hit submit, it uses POST method.Now, different frameworks implement this GET, POST and other APIs also referred to as RESTful APIs in their own way.Java   Java is by far the oldest and the most used language for backend development. It is also used for a variety of other tasks like Android development, but it shines in the backend because of its multithreading abilities. So, enterprise grade web-apps and web-apps with a lot of traffic prefer Java, because it handles loads better. The most popular frameworks for backend development in Java are Spring Framework and Hibernate. Some good beginner's tutorials are - 1. Spring framework2. Hibernate3. JavatpointJavaScript   It is a very popular choice for backend development, because on the frontend side JavaScript is the only choice. So, a lot of frontend engineers can take this choice to become Full-stack developers. Node.js   It allows developers to use JavaScript to write server-side code, through which they can write APIs. Actually, the API part can be done by numerous frameworks of Node.js out of which Express is widely used. The other popular framework is Fastify. Some good beginner's tutorials are - 1. Nodejs2. ExpressJs3. fastifyPython   Python is one of the most popular languages among developers and has been used in a variety of fields. The two most popular frameworks for Python are Flask and Django. Some good beginner tutorials are - 1. Flask2. DjangoC#   It is a very popular programming language which was developed by Microsoft and it has the power of C++. Its popularity increased once the .NET framework was released for backend development. As Microsoft is very popular in enterprises, the .NET framework is generally preferred in enterprises. A good tutorial to learn .NET is - 1. Dotnet2. Dotnet FrameworkGo  Go language which is also referred to as Golang, has gained popularity in recent years. It is used a lot in Backend programming and the two popular frameworks are Gin and Beego. DatabaseFor a Backend engineer, after making APIs with framework based on language, it's time to learn about Databases. Databases are used to store most of the things which we see in a web-app, from user login credentials to user posts and everything else. In the earlier days we only used to have one type of Database and that was Relational databases, which use tables to store data. Now we have two other categories also, one being NoSQL databases and the other In-memory databases. 1. Relational databases   Relational databases allow you to create, update and delete data stored in a table format. This type of database mostly uses SQL language to access the data, hence is also known as an SQL database. MySQL  It is one of the oldest databases and was released in 1995. It is an open-source database and was very popular in the 2000s with the rise of LAMP (Linux, Apache, MySQL, PHP) stack. It is still widely in use, but there are other popular Relational databases. A good tutorial to learn MySQL is - 1. MySQLPostgreSQL  PostgreSQL, which is also known as Postgres is also an old open-source Relational database, which was released in 1996. But it gained popularity recently, as it goes very well with modern stacks containing NodeJS and other backend technologies. A good tutorial to learn PostgreSQL is - 1. PostgreSQLOracle is the most popular and oldest relational database. It was released in 1979 and still remains the number one preference for enterprise customers. All the big banks and other organizations, run on Oracle databases. So, the knowledge of Oracle is a must in many companies for an Engineer. A good tutorial to learn Oracle is - 1. OracleMS-SQL  MS-SQL is also known as Microsoft SQL and is yet another commercial Relational database. It has got different editions, used by different audiences. It is also heavily used by enterprise users and powers a whole lot of big systems around the world. A good tutorial to learn MS-SQL is - 1. SQLServer2. NoSQL databases  NoSQL databases are also called non-SQL databases. The NoSQL databases mainly store data as key-value pairs, but some of them also use a SQL-like structure. These databases have become hugely popular in the 21st century, with the rise of large web-apps which have a lot of concurrent users. These databases can take huge loads, even millions of data connections, required by web-apps like Facebook, Amazon and others. Beside this, it is very easy to horizontally scale  a NoSQL database by adding more clusters, which is a problem in Relational Databases. MongoDB  It is the most popular NoSQL database, used by almost every modern app. It is a free to use database, but the hosting is charged if we host on popular cloud services like MongoDB atlas. Its knowledge is a must for backend engineers, who work on the modern stack. MongoDB uses json like documents to store data. A good tutorial to learn MongoDB is - 1. MongodbIt is a proprietary database service provided by Amazon. It is quite similar to MongoDB and uses key-value pairs to store data. It is also a part of the popular AWS services. A good tutorial to learn DynamoDB is-DynamoDBCassandra is an open-source and free to use NoSQL database . It takes a different approach when compared to other NoSQL databases, because we use commands like SQL, which are known as CQL (Cassandra Query Language). A good tutorial to learn Cassandra is - Cassandra3. In-memory databases   The in-memory database is a database, which keeps all of the data in the RAM. This means it is the fastest among all databases.  The most popular and widely used in-memory database is Redis. Redis  Redis (Remote Dictionary Server) is an in-memory database, which stores data in RAM in a json like key-value format. It keeps the data persistent by updating everything in the transaction log, because when systems are shut down their RAM is wiped clean. A good tutorial to learn Redis - RedisStorageStoring the data is an important part of any application. Although this is mainly DevOps territory, every backend developer should know the basics for the same. We need to store the database data and also the backend code. Beside this the frontend code must also be stored somewhere. Nowadays everything is stored in the cloud, which is preferred by individuals, startups and enterprises. The two most popular cloud-based storages are – Amazon S3 Azure Blob Storage Good beginner's tutorials for both areServices and APIsThese are theoretical concepts and are implemented by various services, but a backend engineer should know them and how to use them. Restful APIs  This is by far the most popular way to get data from a database. It was made more popular, with the rise of web-apps. We do GET, PUT, POST and DELETE operations to read, update, create or delete data from databases. We have earlier discussed different languages and frameworks, which have their own implementations for these operations. Microservices Architecture  In microservice architecture, we divide a large and complex project into small, independent services. Each of these is responsible for a specific task and communicates with other services through simple APIs. Each service is built by a small team from the beginning, and separated by boundaries which make it easier to scale up the development effort if needed. GraphQL  It is the hottest new kid in the block, which is an alternative to the Restful APIs. The problem with Restful APIs is that if you want some data stored in database, you need to get the whole data sent by the endpoint. On the other hand, with GraphQL, you get a query type language which can return only the part of the data which you require.  DevOps & DeploymentA backend engineer requires a fair bit of DevOps knowledge. So, we will next deep dive into the methodologies in DevOps. 1. Containerization & Orchestration   Containers are a method of building, packaging and deploying software. They are similar to but not the same thing as virtual machines (VMs). One of the primary differences is that containers are isolated or abstracted away from the underlying operating system and infrastructure that they run on. In the simplest terms, a container includes both an application’s code and everything that code needs to run properly. Container orchestration is the automatic process of managing the work of individual containers for applications based on microservice architecture. The popular Containerization and Orchestration tools are – Kubernetes Docker Good beginner's tutorials for both are -Kubernetes2. DevOps   DevOps is a set of practices that combine software development (Dev) and IT operations (Ops). It aims to shorten the systems development life cycle and provide continuous delivery with high software quality. The two most popular DevOps services are AWS and Azure. Both of them are cloud based and are market leaders. Both of these platforms contain a wide variety of similar services. AWS  It consists of over 200 products and services for storage, database, analytics, deployment, serverless function and many more. AWS is the market leader as of now with 33% of market share. The AWS certifications are also one of the most in-demand certifications and a must for frontend engineers as well as Backend engineers. Azure  Microsoft Azure is second in terms of market share of cloud-based platforms, with 18% of the market. It also consists of SaaS (Software as a Service), PaaS (Platform as a Service) and IaaS (Infrastructure as a Service) like AWS. 3. PaaS (Platform as a Service)   There are several smaller players, which provide Platform as a Service and are much easier to use than services like AWS and Azure. With these services you can directly deploy your React or other web-apps, by just hosting them on GitHub and pushing the code. These services are preferred a lot by freelancers, hobbyists and small companies as they don’t require investment in learning complicated services like AWS and Azure. The three most popular PaaS services are Digital Ocean Heroku Netlify 4. Serverless  Serverless computing is an execution model where the cloud provider (AWS, Azure, or Google Cloud) is responsible for executing a piece of code by dynamically allocating resources and only charging for the number of resources used to run the code. The code is typically run inside stateless containers that can be triggered by a variety of events including http requests, database events, queuing services, monitoring alerts, file uploads, scheduled events (cron jobs), etc. The code that is sent to the cloud provider for execution is usually in the form of a function. AWS Lambda  It is an event-driven, serverless platform which is part of AWS. The various languages supported by AWS Lambda are Node.js, Python, Java, Go, Ruby and .NET. AWS Lambda was designed for use cases such as updates to DynamoDB tables, responding to a website click etc. After that it will “spin down” the database service, to save resources. Azure Functions  They are quite similar to AWS Lambda, but are for Microsoft Azure. Azure functions have a browser-based interface to write code to respond to events generated by http requests etc. The service accepts programming languages like C#, F#, Node.js, Python, PHP and Java. Serverless Framework  It is an open-source web-framework written using Node.js. The popular services like AWS Lambda, Azure functions and Google cloud functions are based on it. CI/CD A backend developer should know the popular CI/CD (Continuous Integration/Continuous deployment) tools. These tools help to automate the whole process of building, testing and deployment of applications. Github Actions   It is a freely available CI/CD pipeline, which directly integrates to your GitHub based project and can be used in variety of languages. Jenkins  Jenkins is the most popular CI/CD automation tool, which helps in building, testing and deployment of applications. Jenkins was written in Java and over the years has been built to support over 1400 plugins, which extend its functionalities. Circle CI  Circle CI is also a CI/CD automation tool, which is cloud based and so it is different from Jenkins. It is much easier to use than Jenkins, but has a smaller community and lower user base. SecuritySecurity is an important aspect of any application. Most applications containing user personal data, like email etc, are often targeted by hackers. OWASP   The Open Web Application Security Project (or OWASP), is a non-profit organization dedicated to web application security. They have free material available on their website, making it possible for anyone to improve their web application security. Protecting Services & databases against threats   Hackers target databases of popular web-apps on a regular basis to get sensitive information about their customers. This data is then sold to the highest bidder on the dark-net. When such public breaches are reported, then it's a reputation loss for the enterprise also. So, a lot of emphasis should be given to Authentication, Access, Backups, and Encryption while setting up a database. The databases should also be monitored for any suspicious activities. Besides this the API routes also need to be protected, so that the hacker cannot manipulate them. Career roles Most of the companies hire Frontend developers, Backend developers and DevOps engineers separately. This is because most of the enterprise projects are huge, in which roles and responsibilities are distributed. But there is a huge demand for Full Stack developers in the startup sector in US and India. These companies need specialists who can get the product out as soon as possible with agile and small teams. Top companies hiringAlmost every company on the planet is hiring web-developers or outsourcing the development work. Since the past decade, the demand for developers has risen exponentially. The top technology companies which hire full stack developers are Facebook, Amazon, Apple, Netflix, Google, Uber, Flipkart, Microsoft and more.  The sites of each of these companies are web-apps (excluding Apple and Microsoft), with complex frontend and backend systems. The frontend generally consists of React or Angular and the backend is a combination of various technologies. The DevOps part is also quite important in these web-apps as they handle millions of concurrent connections at once.Salaries  The salary of a beginner Frontend developer in India starts from Rs. 300,000($ 3980) per year in service-based companies to Rs. 12,00,000($ 15,971) per year in the top tech companies mentioned above. The salary of a Beginner Full-Stack developer in India starts at Rs. 4,50,000 ($ 5989) per year in service companies to Rs. 12,00,000($ 15,971) per year in top tech companies. The salary for an entry level Frontend developer in USA is $ 59,213 per year and for an entry level Full stack developer is $ 61,042 per year.Below are some sources for salaries. web-developerfull-stack-developerfront-end-vs-back-endTop regions where there is demand There are plenty of remote and freelancing opportunities in web-development across the world. The two countries with most developers and top tech companies are USA and India. Silicon Valley, which is the San Francisco Bay Area, in Northern California, USA is the hub of technology companies.  The top city in India to start a developer job is the Silicon Valley of India – Bengaluru. The number of jobs is more than all the other cities combined and it also has a very good startup ecosystem. Almost all the big technology companies mentioned earlier and top Indian service companies are located in the city. After Bengaluru, the city where the greatest number of technology jobs are based is Hyderabad, followed by Chennai and then Pune. Entry PointsThe demand for web-developers is high and anyone with a passion for creating apps can become a web-developer. An Engineering degree is not mandatory to land a job as a web developer.  The most in-demand skill today and for the next 5 years is React and its ecosystem. So, if you know HTML, CSS, JavaScript and React, it is impossible to not get a job. Career Pathway  Most people start as an intern Front-end developer or Intern Full-Stack developer and in many cases Intern Backend developer. Many companies directly hire junior Frontend/Backend/Full-stack developers.  After that, the next step is the role of Senior Frontend/Backend/Full-stack developers. Many Frontend and Backend developers become full stack developers at this level, by learning additional technologies. Senior resources in Frontend/Backend/Full-stack can then go on to assume Team Lead roles. These people manage small teams in addition to being individual contributors.  After this a professional can become a Project manager, whose main responsibility is managing the team. Another role is that of Technical Project Manager, who manages the team and also has hands-on knowledge in Technology. The last role at this level is that of a Software Architect, who handles and designs big projects and has to look at every aspect of the technology to create the enterprise app. Generally Full-stack developers are preferred in this role, as they need to know all technologies. The highest career milestone is CTO or Chief Technology Officer, who handles all the technology teams and makes all technology decisions in a Technology company. Job SpecializationThere are some Full stack development specializations which I see nowadays in the industry. Full stack developers who work with React in the Frontend and Java in the Backend are in great demand. Similarly, developers who work with Angular in the Frontend and .NET in the backend are in great demand.How KnowledgeHut can helpAll these free resources are a great place to start your Frontend or Full-Stack journey. Beside these there are many other free resources on the internet, but they may not be organized and may not have a structured approach.  This is where KnowledgeHut can make a difference and serve as a one stop shop alternative with its comprehensive Instructor-led live classes. The courses are taught by Industry experts and are perfect for aspirants who wish to become Frontend or FullStack developers.Links for some of the popular courses & Bootcamps by KnowledgeHut are appended below-CSS3JavaScriptReactJSNodeJSDevopsFull-stack developer BootcampFront-end developer Bootcampback-end developer BootcampConclusion This completes our article on the Full stack developer journey by combining both the Frontend and backend roadmap. There are many people who become backend developers first by working on languages like Java and then go on to learn React to become full stack developers.  Again, many developers learn front-end development first with frameworks like React, and then become full stack developers by learning Node.JS. This path is easier for developers because both React and Node.JS use the same language which is JavaScript.We hope you have found this blog useful, and can now take the right path to become a full stack developer. Good luck on your learning journey!
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How To Install and Setup React Native on Mac

React Native Development Environment Installation:With the rapid growth of online websites, businesses, and the general ecosystem, it is crucial that website UIs load quickly on smartphones to encourage smartphone-based internet consumption. Facebook developed React Native from a need to generate UI elements efficiently, which formed the basis for creating the open-source web framework. Its native cross-platform capabilities allow usage for a wide range of platforms for application development, including Android, Web, Windows, UWP, tvOS, macOS, iOS, and AndroidTV. Microsoft also released a preview release in May 2020 that expanded the range of the React Native world, allowing desktop app development. React Native runs in the background of the destination device, and then communicates with the native platform via a batched asynchronous bridge. Its three main advantages are:It allows faster development due to its native natureThough it has a syntax styling similar to CSS or HTML, it is much quicker and efficientIt is flexible as it allows developers to write native code in various languages, including Java, Kotlin, and Swift.This article is about how to install and configure React Native CLI environment. First, we will learn how to install the framework, then check whether it works well and finally develop an app.PrerequisitesBasic computer proficiencyAn account with Administrative privileges on your computerAccess to the outlined documents and softwareA working internet connection to download the installation filesAudienceThis article guides first-time React Native users, junior developers, and developers with no experience with React Native. If curiosity nudged you to learn the framework due to the hype around React, then this is the guide you need.System requirementsSoftwareXcode version 11.3.1 or newer is required. Nodejs version 12 LTS or newer is required.HardwareMacOS requires a Mac device to operateRam - 4GBStorage - 10GBThese requirements ensure your tools run quickly and have enough storage for installation and development.System RequirementsReact Native requires macOS High Sierra (10.13) or higher to run efficiently.Installation through HomeBrew:HomeBrew is a package manager that helps you install and manage packages on Mac, and thus it will be essential to our installation process. You will install HomeBrew so that you can use it to install all the other tools necessary for React Native environment, including Nodejs, git, Watchman, and JDK.First download HomeBrew using the above link, then execute the command below in the Command Line Interface:brew—versionThe command verifies whether HomeBrew has been successfully installed and outputs the specific version installed as the following result shows:homebrew 2.1.7 homebrew/homebrew-core (git revision f487; last commit 2020-05-26)When the version is unavailable, you can install HomeBrew via this code:/usr/bin/ruby -e “$(curl –fsSL https://raw.githubusercontent.com/HomeBrew/install/master/install)”After installation, check whether HomeBrew has installed properly using the following command:brew--versionIf the software is well installed, the result will show the version and date as shown:homebrew 2.1.7 homebrew/homebrew-core(git revision f487; last commit 2020-05-26)NodejsReact Native is a JavaScript platform; hence it needs Nodejs to provide a JavaScript runtime.  Nodejs also provides essential tools such as a local webserver with live reloading, network tools, command-line tools, and web APIs.Use the HomeBrew command below to install Nodejs:brew install nodeCheck whether the installation is successful through the following command:node—versionIf the installation has occurred successfully, the Nodejs version will show up:V12.6.0Installation of Nodejs also includes installation of npm, the Node Package Manager. It would help if you had npm to help you install packages, libraries, and vital tools for your React development environment. To verify if npm is successfully installed, execute the following command:npm—versionIf the installation is successful, you will see the version as shown below:6.9.0WatchmanWatchman monitors the files and folders utilized by the framework and triggers specific actions if the files are modified. It would be best if you had Watchman for React Native to monitor source codes and rebuild them once they are changed.To install Watchman, execute the command below:brew install watchmanVerify installation through:watchman --versionif properly installed, the result will show the version as shown below:4.9.0React Native CLIYou need React Native CLI to develop the app by react-native. React Native CLI is installed by executing the npm command below:npm install --g react-native-cliCheck if the installation is successful using the following command:react-native --versionSometimes, users may get an error when using the npm install --g react -native-cli command. To avoid this, try entering sudo before this command, then enter your system password.If the installation is successful, you will see the version as shown:react-native-cli:2.0.1 react-native:n/a - not inside a React Native ProjectXcodeYou need Xcode for iOS app development, and you can download it via the above link. After installation, configure the Command Line Tools. Execute Xcode and go toXcode > Preferences > LocationsYou should see the Command Line Tools settings showing the version of Xcode as:Xcode 10.2.1 (10E1001)If the settings do not look like that, select the last version of the Command Line Tool from the dropdown menu.Go to components and select an iOS emulator, then download it (this is for those without iOS devices to run and test their apps on. It is also easier than using an actual device.)Move account tabs, select apple id, and input your apple id.Open Xcode and create a new project, name it anything, then close it. After project creation, click the root file and select "sign in and capabilities," then select your user id. Select your emulator and keep it ready for development.CocoapodsCoacoapods manages dependencies in iOS development, and thus it is necessary to develop an app by react-native.Install Cocoapods through the following command:sudo gem install cocoapodsVerify installation through:pod --versionif installation is successful, you can see the version as shown below:1.7.5JDKThe Java Development Kit is essential for the development of Android apps with react-native. Install JDK through the command below:brew tap AdoptOpenJDK/openjdk brew cask install adoptopenjdk8Verify installation through:java -versionIf you see the Java version as shown below, then Java has been successfully installed:openjdk version "1.8.0_222" OpenJDK Runtime Environment (AdoptOpenJDK)(BUILD 1.8.0_222-b10) OpenJDK 64-Bit Server VM (AdoptOpenJDK)(build 25.222-b10, mixed mode)JDK Installation also installs the Java Compiler, which can be verified by executing the following command:javac -versionIf the installation is successful, the following result shows up:javac 1.8.0_222Android StudioAndroid Studio is also an essential tool for developing an Android app using react-native.CONFIGURATIONOn the install type screen, select the custom option, choose your preferred theme, then select the performance (Intel R HAXM) option and Android Virtual Device option. Click Next, then leave the Emulator settings as they are, and click next again. Allow the standard installation to continue and click Finish to complete the process.ANDROID STUDIO SDK CONFIGURATIONClick Configure>SDK Manager and proceed to Android SDK Configuration.Select the Show Package Details option and select the following options:Android SDK Platform 28Intel  X86 Atom System ImageGoogle APIs Intel x86 Atom System ImageGoogle APIs Intel x86 Atom_64 System ImageClick ok to install the options selected.In the SDK Tools Window, select show package details >Android SDK Build Tools >Android SDK Build Tools 23.0.1.ANDROID STUDIO ENVIRONMENT VARIABLE CONFIGURATIONYou need to set environment variables to ensure the development environment fits your specifications.  Ensure that the ANDROID_HOME environment variable connects to your existing Android SDK to avoid complications.Open and include the following code to the ~/.bash_profile file or the ~/.zshrc file to add the environment variables:For .bash_profile users, use the following command:source ~/.bash_profileAfter configuration, restart the terminal, then execute the following command: adbThe correct result if all variables are successfully configured is:Android Debug Bridge Version 1.0.41 version 29.0.1-5644136 Installed as /Your Android SDK Directory Location/platform-tools/adbGit1.You can also use git, which comes with Xcode. However, if its unavailable, run the code below:brew install gitgit is a substitute for the Android Studio development environment.Gradle DaemonSometimes you may need to modify the java code, in which case, your development speed will be affected. Gradle Daemon is a tool that manages these changes to speed up your development.Other Installation MethodsExpo CLIExpo CLI is a tool built to install and manage react-native frameworks. However, its unsuitable feature is that it has numerous native features, which makes building an app tedious and also makes the app size more extensive than it needs to be. Additionally, incorporating elements in an app that are not available in Expo CLI is difficult, making the tool unsuitable for developers. Despite that, Expo CLI has many useful native tools, unlike React Native CLI, such as geolocation, camera, the microphone that can come in handy for most application needs. Expo CLI is a much easier route than the react-native CLI route.The installation process is as follows:1.Install the Expo CLI command line utility using:Npm install –g expo-cli2.Run the command below to create your first project:expo init my app3. Browse to the directory with the following command in the terminal:4. Finally, run the projectExpo start5. A development environment server will be started by these commands. Running the app requires installing the Expo client app to your device (iOS/Android) then connecting it to your computer. Android requires scanning the QR code on the terminal to authenticate the project, while iOS requires QR code scanning using the camera app. On the Android (emulator/real device), use the following command to initialize the app:npm run android6. While on the iOS emulator run:npm run iosExpo has docs that you can reference for solutions or even utilize the Expo Forums created for the Expo community to ask questions.Expo is mostly best suited for beginners as it does not include the use of native code thus cannot be used to develop complex applications with custom components.TestingProject structureReact Native project structure consists of a project directory with configuration files such as package.json, app.json, .watchman.json at the root; separate Android and iOS folders; a _tests_ folder with validation tests for the project; a nodes_module for housing smaller app modules; and an index.js file that maps the application and serves as the initialization point of the application. package.json  specifies project dependencies and versions, while app.json contains the app name.The npm (node package manager) manages the node_modules folder, which stores all the project library dependencies. You should avoid modifying the files present in the folder since alterations performed cannot be assured to be stable from updates/installs. Assets in the public folder are to be shared publicly. The src folder contains all development work by the developer, including components and source codes.Developing an app1. First, you need to lock the version you build with to ensure the app still works even after updates, using the following command:npm config set save-exact=true2. Create a native project through the command:react-native init AwesomeProject cd AwesomeProject react-native run-iosYour new app will run successfully in the emulator.3. In iOS, execute the command below:cd SampleApp #react-native run ios npm run iosThe react-native app will show up on the emulator.4. On Android, run the following command:cd SampleApp #react-native run-android npm run androidYour Android emulator will output:Welcome to ReactSecond App VerificationHello World is a simple program for most development environments. Open index.ios.js for iOS or index.android.js for Android, then proceed to delete everything between the tags .  Write Hello World and execute the emulator.The result will be Hello World on the screen.Modifying Your AppAfter successful testing, you can modify your app through the following steps:Open index.ios.js or index.android.js and edit some files.Click CommandX + R in the iOS Emulator and reload to see changes.Potential issuesYou might encounter problems while installing Cocoapods or React Native CLI - the most probable solution is entering a sudo command before the installation command, which will prompt you for your system password. Input the password, and your installation will go through just fine. You might also get this result [Broken AVD system path. Check your ANDROID_SDK_ROOT value]. Check if you installed android -sdk using homebrew; if you did, then uninstall it through the following command: brew uninstall android-sdk Another error is No ANDROID_HOME which means the bash files do not point to the ANDROID_HOME path. You can correct this through the following steps:Open and add the following code to the ~/.bash_profile file or the ~/.zshrc file to add the environment variables:#export ANDROID_HOME=$HOME/Library/Android/sdk export ANDROID_HOME=android SDK directory location/ Android/sdk export PATH=$PATH:$ANDROID_HOME/emulator export PATH=$PATH:ANDROID_HOME/tools export PATH=$PATH:$ANDROID_HOME/tools/bin export PATH=$PATH:$ANDROID_HOME/platform-toolsFor .bash_profile users, use the following command:source ~/.bash_profileThen proceed to verify the correction using the following code:echo $ANDROID_HOME // default: /Users//Library/Android/sdkAndroid Emulator won't run from Android Virtual Device Manager – Android Studio rarely shows an error that may occur in the Android Device Emulator; thus, you need to utilize the command line and run the commands below to check the name of the Android virtual device:Avdmanager list avdThen runEmulator –avd Wait for the device to boot up, then run your app in the emulatorReact-native run-androidYour app should run successfully.No Connected devices- you should run the following commandReact-native run-androidWrong Android emulator – you need to find the right emulator using the following code:find - -name emulator –type f /Users//Library/Android/sdk/emulator // this /Users//Library/Android/sdk/tools/emulator // not thisRestart the terminal and verify the error is gone.Avdmanager not found- write ~/.bash_profile, then add the following code afterwards:PATH=$PATH:$ANDROID_HOME/tool s/bin export PATHthen runsource ~/.bash_profileQuit and restart the terminal, then run the tools.Uninstallation procedureSometimes you might need to uninstall and wipe off the whole react-native environment due to issues such as a broken development environment which can be caused by misusing commands or assigning storage to variables incorrectly.  To do so efficiently, use the uninstall command together with the -g flag, then include the scope if the package is scoped.  A good example is as follows;npm uninstall -g react-native-cliornpm uninstall for scoped package usenpm uninstall As our installations have a package.json file, you might need to remove a package from the dependencies in that file. Use the following commands to effect these changes:npm uninstall --save or the following for a scoped packagenpm uninstall --save You will also need to verify if the uninstallation is successful through the following commands on macOS:ls node_modulesThis command ensures the node_modules do not contain a folder for the uninstalled files.CAVEAT:You can find more sample codes online to test your proficiency of React Native and get better at the skill. React Native is based on MIT License that grants Facebook copyright for portions of React Native for macOS extension derived from React Native. Remember to only download software from the official stated sites to avoid downloading compromised, malware-ridden software that can cripple your computer. If your computer shows any warning while executing any of the above steps, ensure to verify the software, ask an expert or ask on online community platforms. After completing and understanding all these steps successfully, you are now officially a beginner. You can proceed to the next stages of React Native app development until you become an expert. Some of the most significant areas you need to look at afterwards include animation, command-line instructions, components, shareable APKs, custom fonts, debugging, ESLint, images, layout, HTTP requests, Firebase integration, listview, native modules, and routing.The guide presented has shown how to install React Native through various methods and why the tools stated are required, then showed examples of apps and finally the uninstallation procedure. Tooling and development in React Native are simple, and the learning curve is short, making it an ideal framework for web developers.  The growth of internet consumers, cross-platform development, and the whole of the internet ecosystem is an excellent catalyst for React Native to grow in popularity among developers. It offers them faster development speed while offering internet consumers speedier loading times and more beautiful website UIs.  As you have seen, React development is simple; hence it should convince you to get started and launch your own apps within a short period. Being a new but highly applicable language, React Native holds a lot of opportunities, career wise and development wise. There are also numerous React Native platforms on the internet that can help you solve challenges you might face in development. Keep coding and have fun!
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How To Install and Setup React Native on Mac

React Native Development Environment Installation:... Read More

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 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 mongodb-administrator.
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How to Install MongoDB on a Mac

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