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What Are Callbacks in Node.JS

The callback is an asynchronous equivalent for a function. It is called following every task. In Node.js, callbacks are frequently used. All APIs of Node are drafted in a way that supports callbacks.  To illustrate, when a function commences reading a file, it instantly returns the control to the execution environment to execute the succeeding instruction.In Node.js, once file I/O is concluded, it would call the callback function. There is no hindrance or waiting for File I/O. This presents Node.js as highly scalable, as it can process an extraordinary number of requests without pausing for any function to return results.Understanding the callback pattern for asynchronous programmingIn the asynchronous programming model, something happens one at a time. An asynchronous model acknowledges multiple things to occur at the same time. When you commence an action, your program proceeds to run. When the step completes, the program is acquainted and gets access to the result (for example, the data read from disk).Node.js encourages an asynchronous coding method from the ground up, in contrast to several popular web frameworks. There are numerous vital things to be conscious of when learning to write asynchronous code – and at the same time, you will frequently find your code executing in highly unexpected ways.Various functions in Node.js core have both synchronous and asynchronous versions. It will be far better to use asynchronous operations in most conditions; otherwise, why use Node.js?Asynchronous continuation-passing techniquelet's consider an example where a function is asynchronous, which is as follows:function exampleAsync(a, b, callback) {   setTimeout(function() {     callback(a + b);   }, 100); } console.log('Before asynchronous call’); exampleAsync(2, 3, function(finalresult)   {     console.log('Result: ' + finalresult); }); console.log('After asynchronous call');OutPut:Before asynchronous call After asynchronous call Result: 5setTimeout() triggers an asynchronous process; it will not wait for the callback to get executed. It returns quickly, providing the control back to exampleAsync(), and then back to its caller.The following image shows how this works:Examples of the callback pattern in Node.jsA callback is a function called when the task finishes, and a callback function allows other code to run in the meantime. Using the Callback concept, Node.js can process many requests without waiting for any function to return the result, making Node.js highly scalable. For example: In Node.js, when a function starts reading the file, it returns the control to the execution environment immediately to execute the next instruction. Once file I/O gets completed, the callback function will get called to avoid blocking or wait for File I/O.Example 1: Reading a file synchronously in Node.js. Create a text file synch.txt with the following content:Hello, this is my first testing of synchronous content.Create a first.js file:var fs = require("fs"); var datatxt = fs.readFileSync('synch.txt'); console.log(datatxt.toString()); console.log("Execution ends");Output:Hello, this is my first testing of synchronous content.Execution endsInformation: The fs library is loaded to handle file-system associated operations. The readFileSync() function is synchronous and blocks execution till terminated. The function blocks the program until it reads the file, and then only it proceeds to end the program.Example 2: Reading a file asynchronously in Node.js. Create a text file asynch.txt with the content asHello, this is my first testing of asynchronous content.var fs = require("fs");     fs.readFile('asynch.txt', function (ferr, dataasynch) {       if (ferr) return console.error(ferr);       console.log(dataasynch.toString());   });   console.log("Execution ends"); Output:Execution endsHello, this is my first testing of asynchronous content.Information: The fs library is loaded to handle file-system-related operations. The readFile() function is asynchronous, and the control returns immediately to the next instruction in the program while the function keeps running in the background. A callback function is relinquished, which gets called when the task running in the background is finished.Getting trapped in callback hellCallback Hell is an anti-pattern detected in the code of asynchronous programming. It is a slang phrase applied to define a cumbersome number of nested “if” statements or functions. If the application logic gets complex, a few callbacks appear harmless. But once your project demands grow, it is common to fall under piling layers of nested callbacks.The callback is a function where “A” is passed to another function, “B,” as a parameter. The function “B” then executes the code “A” at some point. The invocation of “A” can be immediate, as in a synchronous callback, or it can occur later as in an asynchronous callback.var callbackhell = require(‘fs’) callbackhell.readFile(‘test.json’, function(‘err’, results){ if(err){ console.log(err); } console.log(JSON.parse(results).name) });In the code, we call readFile and pass it as a second parameter function (Callback Hell). readFile will execute the callback bypassing the procedure's results to parameters.The use of callbacks makes the code tedious to write and manage. It increases the difficulty of identifying the application's flow, which is an obstacle, hence the popular name of Callback Hell.What’s more dangerous than callback hell?Not fixing the nested callback hellUsing Promises to write asynchronous codePromises are the function that a value would be returned at a later time. Instead of returning concrete values, these asynchronous functions return a Promise object, which will at some point either be fulfilled or not.A promise represents an asynchronous operation. It means a process that has not been completed yet but is expected to in the future. Let's have a look at a simple file read example without using promises:fs.readFile(filePath, (err, result) => {      if (err) { console.log(err); }      console.log(data); }); if the readFile function returned a promise, the logic would be  written as below var fileReadandPromise = fs.readFile(filePath); fileReadandPromise.then(console.log, console.error)The fileReadandPromise is passed multiple times in a code where you need to read a file. This helps in writing robust unit tests for your code since you now only have to write a single test for a promise. And more readable code!Promise.all()The Promise. all() method accepts an iterable of promises as an input and returns a single Promise that fixes to an array of the input promises' results.const promise1 = Promise.resolve(5); const promise2 = 54; const promise3 = new Promise((resolve, reject) => {   setTimeout(resolve, 100, 'foo'); }); Promise.all([promise1, promise2, promise3]).then((values) => {   console.log(values); });Promise.any()Promise.any() takes an iterable of Promise objects and, as soon as one of the promises in the iterable fulfills, returns a single promise that resolves with the value from that promise. If there are no promises in the iterable fulfill, then the returned promise is rejected with an AggregateError, a new subclass of Error that groups together individual errors. This method is the opposite of Promise.all().const promiseand1 = Promise.reject(0); const promiseand2 = new Promise((resolve) => setTimeout(resolve, 100, 'Large')); const promiseand3 = new Promise((resolve) => setTimeout(resolve, 500, 'Small')); const promises = [promiseand1, promiseand2, promiseand3]; Promise.any(promises).then((value) => console.log(value));Using Async / Await for handling asynchronous codeInitial versions of Node didn't have the Node architecture single-threaded and asynchronous. The intricacy with this kind of code is that this kind of position can create many problems, and the code can get messy when there are several functions, and this situation is called callback hell.Promises and function chaining were introduced to overcome this situation.By Node v8, the async/await feature was finally wheeled out to deal with Promises and function chaining. The functions were not necessarily required to be chained after another; they simply await the function that returns the Promise. But the async function is needed to be declared before awaiting a function returning a Promise.Examples of Async / AwaitThe code looks like the following.async function testfun1(req, res){   let resp1 = await request.get('http://localhost:8080');     if (resp1.err) { console.log('error');}     else { console.log('Response Fetched'); }ExplanationThe code above essentially demands the JavaScript engine driving the code to wait for the request.get() function to accomplish before moving on to the next line to execute it. The request.get() function returns a Promise for which the user will await. Before async/await, if it is required to check that the functions are running in the desired sequence, i.e. one after the another, chain them one after the another or register callbacks. Code review and understanding become comfortable with async/await, as observed from the above example.Error handling in the case of async / awaitFormulating exceptionsAn exception is built using the throw keyword:throw valueAs soon as the above line executes, the standard program flow stops and the control is held back to the most imminent exception handler.Typically, in client-side code, a value can be any JavaScript value, including a string, a number or an object.In Node.js, we don't throw strings; we throw Error objects.Error objectsAn error object is an object that is either an instance of the Error object or extends the Error class provided in the Error core module:throw new Error('Out of Mall') OR class NoPersoninMallError extends Error {   //... } throw new NoPersoninMallError()Exception handlingAn exception handler is a try/catch statement.Any exception created in the lines of code in the try block is as below:try { //code would be written here. } catch (e) {} //e is the exception value. Error handling with async/awaitUsing async/await, the errors can be caught as below:async function AnyFunction() {   try {     await anotherFunction()   } catch (err) {     console.error(err.message)   } } ConclusionNode.js is more beneficial to the developers in association with its disadvantages. What’s more important is that it has extended the JavaScript applications area and can be used for both front-end and back-end servers.Node.js is, without a doubt, one of the more exciting technologies in use today, and it has grown into one of the most popular platforms used for web applications, services, and desktop apps. With time, more and more business organizations have opted to use Node.js and are consistently getting positive results.

What Are Callbacks in Node.JS

2K
What Are Callbacks in Node.JS

The callback is an asynchronous equivalent for a function. It is called following every task. In Node.js, callbacks are frequently used. All APIs of Node are drafted in a way that supports callbacks.  To illustrate, when a function commences reading a file, it instantly returns the control to the execution environment to execute the succeeding instruction.

In Node.js, once file I/O is concluded, it would call the callback function. There is no hindrance or waiting for File I/O. This presents Node.js as highly scalable, as it can process an extraordinary number of requests without pausing for any function to return results.

Understanding the callback pattern for asynchronous programming

In the asynchronous programming model, something happens one at a time. An asynchronous model acknowledges multiple things to occur at the same time. When you commence an action, your program proceeds to run. When the step completes, the program is acquainted and gets access to the result (for example, the data read from disk).

Node.js encourages an asynchronous coding method from the ground up, in contrast to several popular web frameworks. There are numerous vital things to be conscious of when learning to write asynchronous code – and at the same time, you will frequently find your code executing in highly unexpected ways.

Various functions in Node.js core have both synchronous and asynchronous versions. It will be far better to use asynchronous operations in most conditions; otherwise, why use Node.js?

Asynchronous continuation-passing technique

let's consider an example where a function is asynchronous, which is as follows:

function exampleAsync(a, b, callback) {
  setTimeout(function() {
    callback(a + b);
  }, 100);
}
console.log('Before asynchronous call’);
exampleAsync(2, 3, function(finalresult)  
{
    console.log('Result: ' + finalresult);
}); console.log('After asynchronous call');

OutPut:

Before asynchronous call 
After asynchronous call 
Result: 5

setTimeout() triggers an asynchronous process; it will not wait for the callback to get executed. It returns quickly, providing the control back to exampleAsync(), and then back to its caller.

The following image shows how this works:

Asynchronous continuation-passing technique

Examples of the callback pattern in Node.js

A callback is a function called when the task finishes, and a callback function allows other code to run in the meantime. Using the Callback concept, Node.js can process many requests without waiting for any function to return the result, making Node.js highly scalable. For example: In Node.js, when a function starts reading the file, it returns the control to the execution environment immediately to execute the next instruction. Once file I/O gets completed, the callback function will get called to avoid blocking or wait for File I/O.

Example 1: Reading a file synchronously in Node.js. Create a text file synch.txt with the following content:

Hello, this is my first testing of synchronous content.

Create a first.js file:

var fs = require("fs"); 
var datatxt = fs.readFileSync('synch.txt'); 
console.log(datatxt.toString()); 
console.log("Execution ends");

Output:

Hello, this is my first testing of synchronous content.
Execution ends

Information: The fs library is loaded to handle file-system associated operations. The readFileSync() function is synchronous and blocks execution till terminated. The function blocks the program until it reads the file, and then only it proceeds to end the program.

Example 2: Reading a file asynchronously in Node.js. Create a text file asynch.txt with the content as

Hello, this is my first testing of asynchronous content.

var fs = require("fs");     
fs.readFile('asynch.txt', function (ferr, dataasynch) {  
    if (ferr) return console.error(ferr);  
    console.log(dataasynch.toString());  
});  
console.log("Execution ends"); 

Output:

Execution ends
Hello, this is my first testing of asynchronous content.

Information: The fs library is loaded to handle file-system-related operations. The readFile() function is asynchronous, and the control returns immediately to the next instruction in the program while the function keeps running in the background. A callback function is relinquished, which gets called when the task running in the background is finished.

Getting trapped in callback hell

Callback Hell is an anti-pattern detected in the code of asynchronous programming. It is a slang phrase applied to define a cumbersome number of nested “if” statements or functions. If the application logic gets complex, a few callbacks appear harmless. But once your project demands grow, it is common to fall under piling layers of nested callbacks.

The callback is a function where “A” is passed to another function, “B,” as a parameter. The function “B” then executes the code “A” at some point. The invocation of “A” can be immediate, as in a synchronous callback, or it can occur later as in an asynchronous callback.

var callbackhell = require(‘fs’)
callbackhell.readFile(‘test.json’, function(‘err’, results){
if(err){
console.log(err);
}
console.log(JSON.parse(results).name)
});

In the code, we call readFile and pass it as a second parameter function (Callback Hell). readFile will execute the callback bypassing the procedure's results to parameters.

The use of callbacks makes the code tedious to write and manage. It increases the difficulty of identifying the application's flow, which is an obstacle, hence the popular name of Callback Hell.

What’s more dangerous than callback hell?

Not fixing the nested callback hell

Using Promises to write asynchronous code

Promises are the function that a value would be returned at a later time. Instead of returning concrete values, these asynchronous functions return a Promise object, which will at some point either be fulfilled or not.

A promise represents an asynchronous operation. It means a process that has not been completed yet but is expected to in the future. Let's have a look at a simple file read example without using promises:

fs.readFile(filePath, (err, result) => {
     if (err) { console.log(err); }
     console.log(data);
});
if the readFile function returned a promise, the logic would be  written as below
var fileReadandPromise = fs.readFile(filePath);
fileReadandPromise.then(console.log, console.error)

The fileReadandPromise is passed multiple times in a code where you need to read a file. This helps in writing robust unit tests for your code since you now only have to write a single test for a promise. And more readable code!

Promise.all()

The Promise. all() method accepts an iterable of promises as an input and returns a single Promise that fixes to an array of the input promises' results.

const promise1 = Promise.resolve(5);
const promise2 = 54;
const promise3 = new Promise((resolve, reject) => {
  setTimeout(resolve, 100, 'foo');
});
Promise.all([promise1, promise2, promise3]).then((values) => {
  console.log(values);
});

Promise.any()

Promise.any() takes an iterable of Promise objects and, as soon as one of the promises in the iterable fulfills, returns a single promise that resolves with the value from that promise. If there are no promises in the iterable fulfill, then the returned promise is rejected with an AggregateError, a new subclass of Error that groups together individual errors. This method is the opposite of Promise.all().

const promiseand1 = Promise.reject(0);
const promiseand2 = new Promise((resolve) => setTimeout(resolve, 100, 'Large'));
const promiseand3 = new Promise((resolve) => setTimeout(resolve, 500, 'Small'));
const promises = [promiseand1, promiseand2, promiseand3];
Promise.any(promises).then((value) => console.log(value));

Using Async / Await for handling asynchronous code

Initial versions of Node didn't have the Node architecture single-threaded and asynchronous. The intricacy with this kind of code is that this kind of position can create many problems, and the code can get messy when there are several functions, and this situation is called callback hell.

Promises and function chaining were introduced to overcome this situation.

By Node v8, the async/await feature was finally wheeled out to deal with Promises and function chaining. The functions were not necessarily required to be chained after another; they simply await the function that returns the Promise. But the async function is needed to be declared before awaiting a function returning a Promise.

Examples of Async / Await

The code looks like the following.

async function testfun1(req, res){
  let resp1 = await request.get('http://localhost:8080');
    if (resp1.err) { console.log('error');}
    else { console.log('Response Fetched');
}

Explanation

The code above essentially demands the JavaScript engine driving the code to wait for the request.get() function to accomplish before moving on to the next line to execute it. The request.get() function returns a Promise for which the user will await. Before async/await, if it is required to check that the functions are running in the desired sequence, i.e. one after the another, chain them one after the another or register callbacks. 

Code review and understanding become comfortable with async/await, as observed from the above example.

Error handling in the case of async / await

Formulating exceptions
An exception is built using the throw keyword:
throw value
As soon as the above line executes, the standard program flow stops and the control is held back to the most imminent exception handler.

Typically, in client-side code, a value can be any JavaScript value, including a string, a number or an object.

In Node.js, we don't throw strings; we throw Error objects.

Error objects
An error object is an object that is either an instance of the Error object or extends the Error class provided in the Error core module:

throw new Error('Out of Mall')
OR
class NoPersoninMallError extends Error {
  //...
}
throw new NoPersoninMallError()

Exception handling

An exception handler is a try/catch statement.
Any exception created in the lines of code in the try block is as below:

try { 
//code would be written here. 
} catch (e) {} 
//e is the exception value. 

Error handling with async/await

Using async/await, the errors can be caught as below:

async function AnyFunction() { 
  try { 
    await anotherFunction() 
  } catch (err) { 
    console.error(err.message) 
  } 
}

Conclusion

Node.js is more beneficial to the developers in association with its disadvantages. What’s more important is that it has extended the JavaScript applications area and can be used for both front-end and back-end servers.

Node.js is, without a doubt, one of the more exciting technologies in use today, and it has grown into one of the most popular platforms used for web applications, services, and desktop apps. With time, more and more business organizations have opted to use Node.js and are consistently getting positive results.

Rajesh

Rajesh Bhagia

Blog Author

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

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

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

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How to Install Node.JS on Ubuntu

Node.js is a general-purpose programming JavaScript platform that allows users to quickly build network applications. Node.js makes development more consistent and integrated by using JavaScript on both the front and backend, and allows you to write JavaScript on the server-side.JavaScript, as you know, is a browser-based language. The browser's engine will take and compile JavaScript code into commands. The creator of Node.js took the engine of Chrome and set it to work on a server. The language can be interpreted in an environment.In this article, we will read about Node.js installation using three methods:Installing the Stable VersionInstall Using a PPAInstall Using NVMPrerequisitesHardware Requirements:RAM: 4 GBStorage: 256 GB of Hard Disk SpaceSoftware Requirements:Web Browser: Any browser such as Google Chrome, Mozilla Firefox, Microsoft Edge.Operating System: An Ubuntu 18.04 server installed with a non-root sudo user and firewall.Installation Procedure1. Installing the Stable Version for UbuntuIn its default repositories, Ubuntu 18.04 contains a version of Node.js that provides a consistent experience on a number of systems. The version of the repositories is 8.10.0 when it is written. This is not the latest version but should be stable and sufficient for quick language experiments.Step 1: You can use the apt package manager to obtain this version. Refresh your index for your local package with:$ sudo apt updateStep 2: Now, install Node.js from the repository:$ sudo apt install nodejsStep 3: This is all you need to do to get set up with Node.js if the package in the repositories fits your needs. In most cases, the package manager Node.js will also install npm. This can be done by:$ sudo apt install npmThis allows the installation of Node.js modules and packages.The executable from Ubuntu repositories is known as nodejs instead of node because of conflict with another package. Take this into account when you run the software.Step 4: To check which Node.js version you installed, try this:$ nodejs -vYou can decide if you want to work with different versions, package archives, and version managers, after you have established which version of Node.js you have installed from Ubuntu repositories. The following elements will be discussed with more flexible and robust installation methods.2. Install Using a PPAStep 1: First install curl on Ubuntu:$ sudo apt install curlStep 2: To access its contents, install the PPA first. Use curl to retrieve the installation script in your favourite version from your home directory so that your favourite version (if different) replaces 10.x:$ cd ~ $ curl -sL https://deb.nodesource.com/setup_10.x -o nodesource_setup.shStep 3: nano (or your preferred text editor) can be used to inspect the contents of this script:$ nano nodesource_setup.shStep 4: Now, run the script under sudo:$ sudo bash nodesource_setup.shStep 5: You add the PPA to the settings and automatically update your local package cache. You can install the Node.js package in the same way that you did above after running the Nodesource setup script:$ sudo apt install nodejsStep 6: To check the version of Node.js, use:$ nodejs -vThe nodejs package includes the nodejs binary and npm so that you don't have to install npm individually.Step 7: Npm uses a setup file to keep track of updates in your home directory. The first time you run npm, it will be created. To check that npm has been installed and to create a settings file, execute this command:$ npm -vStep 8: You need to install the build-essential package to allow certain npm packages (for instance those that require compilation code from source) to work.$ sudo apt install build-essentialYou now have the tools to work with npm packages, which require source code compilation.3. Install Using NVMAn alternative is to use a tool called nvm which stands for "Node.js Version Manager" when installing Node.js with apt.  You can access the latest versions of Node.js and manage previous releases by controlling your environment with nvm. However, the Node.js versions that you handle are different from the apt versions.Step 1: You can use curl to download the nvm installer from the GitHub project page. 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MongoDB is the most popular NoSQL database among both enterprise and startups, and the fact that it is highly scalable makes it perfectly suited for current web-apps, which need to scale once the user base increases. MongoDB is different from traditional relational databases because it uses json like objects to store data, instead of tables in relational databases.In this post, we will learn to drop a MongoDB database, using MongoDB Drop Database command. Dropping a database means dropping all the collections (tables in MongoDB) in it, along with the indexes. If you don’t want to drop the entire database, you can drop individual collections.PrerequisitesWe are using Windows 10 in this tutorial. Please make sure you have downloaded the MongoDB Community Server and installed it. It is a very easy setup and you will find a lot of good articles on the internet to guide you through this process. Do make sure that you have added it in the Environment variable in your PC. We have also created an example database, which contains a collection named products.OverviewDropping a database is quite simple and can be done with three methods from the command line and also by any GUI (Graphical User Interface) tool, which is used to connect with the running MongoDB instance.To delete a MongoDB database through the command line, we mainly use db.dropDatabase(). We will first understand how to do this.Drop Database definitionAs mentioned earlier, we drop a database in MongoDB, or delete MongoDB database using the db.dropDatabase() command.db.dropDatabase()This removes the current database, deleting all collections inside it, along with the indexes.writeConcern is the optional parameter, which is a document expressing the write concern to use, if greater than majority. Write concern can include the following fields:{ w: , j: , wtimeout: }w option is used to request acknowledgement, that the write operation has passed to a specified number of mongod instances.j option is used to request acknowledgement, that the write operation had been written to the disk-journalwtimeout option is used to specify the time limit, to prevent the write operations from blocking indefinitely.Using the w option, the following are available:w: 1 – Requests acknowledgement that the write concern has passed to the single mongod instance. It is also the default option.w: 0 – Requests no acknowledgement of the write operation.w: “majority” – It requests acknowledgement that the write operation has passed to the majority of primary and secondary servers.Now, we will look into the j option values.j: true – It requests acknowledgement that the different mongod instances, mentioned in w: , have been written to the on-disk journal.The wtimeout option specifies the time limit in milliseconds, for the write concern. It causes write operations to return with an error after the specified limit.dropDatabaseWe can also use the dropDatabase command directly to delete MongoDB, current database. The command has the following form.{ dropDatabase: 1, writeConcern: , comment: }This command optional fields are-writeConcern is the optional parameter, which is in the form of a document expressing the write concern to use if it is greater than majority. We have just looked into it in detail earlier.comment is a user provided comment, which is attached to this command. Once set, this will appear in the logs.Dropping with dropDatabase CommandWe can drop the database through dropDatabase command. I am connected to my local mongoDB instance from the windows terminal, by giving the mongo command.> mongoAfter that to show all the databases in my MongoDB database, we will use the command show dbs command. It will show all our databases. Out of it I created the example database only.> show dbs admin    0.000GB config   0.000GB example  0.000GB local    0.000GBNow, to drop the example database, first we have to go inside it by using the use example command.> use example switched to db exampleNow, we will use the dropDatabase command from within a db.runCommand(). Now, the runCommand runs the command in the context of the current database. This means it will run the dropDatabase command in the current database, which is seen in this example:> db.runCommand( { dropDatabase: 1 } ) { "dropped" : "example", "ok" : 1 }As discussed, the earlier dropDatabase command accepts an optional writeConcern argument, and also a comment field. The syntax then is written as shown below.{ dropDatabase: 1, writeConcern: , comment: }Dropping with dropDatabase() MethodWe can drop the database through db.dropDatabase() method also. It also removes the current database, deleting all associated files.Once again connect to mongoDb database by giving the command mongo. After that we can check all the databases with show dbs command.For db.dropDatabase() method also, we need to go inside the database that we are dropping, by using use command.Now, we will use the db.dropDatabase() command to drop the database, which is example in our case.> db.dropDatabase() { "dropped" : "example", "ok" : 1 } The db.dropDatabase() method also accepts an optional writeConcern argument. The syntax then becomes: { w: , j: , wtimeout: }Dropping with Unix Shell and Eval commandThis method only works in a Unix environment like Ubuntu, Mac or WSL2 for Windows. Here, the mongo command with the database name can be used to connect to a specific database. For example, to connect to the example database, we can use the below command.$ mongo exampleNow, we can drop our example database with one line command, where we use the eval command followed by the JavaScript code that we wish MongoDB to execute. As seen earlier to drop the database, we use the db.dropDatabase() command. Now, we will wrap this method in printjson function, to get the output of the command.$ mongo example --eval "printjson(db.dropDatabase())" MongoDB shell version: 3.0.9 connecting to: example { "dropped" : "example", "ok" : 1 }Dropping with MongoDB CompassNow we can drop a database or delete MongoDB database very easily using a Graphical tool like MongoDB compass. Infact this tool was auto-downloaded when I had installed MongoDB on my Windows machine.So, first open the MongoDB Compass and you will see the option to connect to a database. We want to connect to our local database, in which the hostname is localhost and port is 27017. These are the default values for all MongoDB connections, unless you changed it during installation.Don’t change anything and click on the Connect button.We are now connected to the MongoDB running on our localhost and we can see all the databases including example database. Next, hover over example database, which will show a delete button. Click on the delete button.We will be shown a pop-up where we have to write the name of our database, which is example in our case. Then click on the DROP DATABASE button, to MongoDB remove database.After that it will take us back to the earlier screen and we can see the example database is dropped.ConclusionIn this article, we have learned about the different MongoDB delete database commands. We have also learned about the write concern optional parameter, which can be passed to both db.dropDatabase() method and dropDatabase command. This parameter is mainly used in large database systems, which have several servers. We hope you found this article useful! Keep learning.
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How to Drop a MongoDB Database?

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The 2021 Learning Path To Becoming a Full Stack Web Developer

Full stack developer roles are among the hottest careers in the tech space now. These talented folks can develop a whole product from scratch. A full stack developer is a combination of Front-end developer and Backend developer. These two in themselves are full time jobs and most people make careers out of one of them. So, we will start with Front-end roadmap and then go to Back-end roadmap. A person interested in becoming a Full-stack developer needs to have proficiency in both the front end and back-end tools, just like I started as a Front-end developer and later on become a Full stack developer by mastering JavaScript backend technologies and databases.The demand for Full Stack Web DeveloperThe demand for Full stack developers is the highest in early-stage startups, where they want to create a Minimum Viable Product at the earliest to showcase to the investors. It is also a nice skill to have in addition to frontend technologies or backend technologies alone, since an employer prefers people with both skills.There are a lot of technologies to learn to be a Full-Stack developer. We will discuss about them in the coming sections.   List of technologies to master to become a Full-Stack developer A full-stack developer is actually a combination of Frontend developer and Backend developer. We need to master both, and both have different Roadmaps. Let’s start with the basics. The frontend is the web-site which we see and it is primarily made with HTML and CSS.  JavaScript was also used earlier but nowadays, it is created with JavaScript frameworks like ReactJS, Angular or Vue. All these frameworks require one to learn the basics of HTML, CSS, & JavaScript. So, we need to learn the basics followed by at least one framework.In the backend we have a lot of technologies and databases also. So, we need to choose one backend framework from Java (Spring Framework), JavaScript (NodeJS) etc and then also learn databases. Databases are divided into two categories, which is NoSQL(MongoDB) and SQL(PostgreSQL, MySQL, Oracle) databases. So, you need to choose one of the databases.We are also required to know about DevOps, which is a practice of harmonizing development and operations whereby the entire pipeline from development, testing, deployment, continuous integration and feedback is automated. The knowledge of either AWS or Azure based cloud ecosystem is required, and also CI/CD like Jenkins and containerizing & orchestrating applications using Docker and Kubernetes.1. Frontend RoadmapLearn the BasicsPlease refer to the attached figure for Front-end roadmap, as we will be referring to this throughout this article. We have to start our journey by learning HTML, CSS and JavaScript which is the base for a web-app or website. HTML has changed a bit over the years, with the introduction of HTML 5 and semantics tags, so make sure to update yourself. JavaScript which was released in 1995, didn’t change much during the next 20 years. But once more and more developers started using it, the ECMA committee decided to add some very nice features and enhance the language, and renamed it ES6 in 2015. After that they regularly added new features to the language and have just released ES2020 in June 2020, which has many additional features. So, learn the basic JavaScript first and then upgrade to ES6 and newer versions. CSS is what makes a website or web-app beautiful, and is often considered the hardest part by a developer. Earlier, CSS was very confusing and had a steep learning curve, because of the use of floats to create a layout. Developers usually used to work with CSS frameworks like bootstrap to design a site. But things have changed a lot with the invention of CSS Grid and Flexbox. Some of the best resources to learn the basics are - html.specdeveloper.mozilla.HTMLStyle CSSdeveloper.mozilla.CSSdeveloper.mozilla.JavaScriptGetting Deeper Now, just learning JavaScript and some basic CSS will not make you a good Front-end developer as you have to take a deep dive into JavaScript. We will discuss CSS later, after learning the essentials of JavaScript.JavaScript EssentialsThere are many things associated with JavaScript which we need to learn before moving forward.The Terminal The first thing to learn is to work in a terminal, and master some of the basic commands. If you are on a Mac, it’s already based on Linux and runs most Linux commands. If you are working on Windows then you must install git bash, which will give you a Linux environment to work with. In JavaScript frameworks, we need to run a lot of commands from the terminal, like if we want to install a third-party dependency by npm.  The basics of Linux can be learnt from their official site.Version ControlNext, learning version control is very important because we should always keep our code in some remote repository like Github. The industry works on Git, which is version control software. It is completely command-based and is used heavily everywhere. Learn the basic commands which will be useful even for an individual developer. Later on, when working with teams, more advanced knowledge of the git command is required.Through the git commands, we store our code in repositories. The most popular ones are Github and Bit Bucket, so we need to learn how to store and link them.The basics of git can be learnt from this awesome tutorial.freecodecamp.orgTask Runners Task runners are applications which are used to automate tasks required in projects. These tasks include minification of JavaScript and CSS files, CSS preprocessing like from SASS to CSS, image optimization and Unit testing. The three popular task runners are npm scripts, gulp and grunt. The npm script is nothing but the package.json file which comes with React projects or is created in a Node.js project using npm init. Gulp and Grunt are much bigger applications and also have a plugin ecosystem that is suited for large JavaScript projects. The basics for these two technologies can be learnt from here. Module Loader and Bundler Both module loaders and bundlers are required for large JavaScript applications. Knowledge of both is required, if the project you are working is a big Vanilla JavaScript project. When a large JavaScript application consists of hundreds of files, the module loader takes care of the dependency and makes sure all the modules are loaded when the application is executed. Examples are RequireJS and SystemJS.Module bundlers also do the same thing, building it at the time of application build rather than at the runtime. Popular examples are Webpack and Rollup. Testing Testing nowadays is very important in any type of project. There are two types of testing; one is known as Unit testing and other as end-to-end testing. For unit testing we write test cases and the most popular tool nowadays is Jest. End-to-end testing is automated testing, which emulates the whole app. Suppose, an app has a login screen and then it shows posts. The testing tool will run the web-app to check whether all the functionalities are done correctly. The two most popular options today are Puppeteer and Cypress. The tutorials to refer for these topics are - Libraries and FrameworkThey are the most important part of the JavaScript ecosystem nowadays. It all started with the release of AngularJS in 2010. Before that period most enterprise apps were made in Java and were desktop apps. But AngularJS changed everything, because it made it easy to manage big projects with JavaScript and helped to create complex web-apps.1. React It is the most popular JavaScript library today and is used by both enterprises and startups that have a huge ecosystem. It is not a complete framework like Angular and we have to install third party dependencies for most things. But if you want to learn a framework that will get you a job, then that framework would be ReactJS, and its demand is not going away for the next 5 years. The component approach and its easy learning curve have made React more popular than other frameworks. A good starting tutorial for React isState Management In React state management can sometimes become complex, when we need to share data between components. We generally take help of external packages in it with the most popular being Redux. But we also have other state management libraries like XState and Recoil. Server-side rendering With performance becoming important nowadays, Server-Side Rendering speeds up the React projects even faster. In SSR projects, the React code is rendered on the server and the client browser directly receives the HTML, CSS, JS bundle. The only framework to do it is NextJS. Static Site Generators Lot of sites don’t need to be updated frequently and it is the place where the only Static Site Generator for ReactJS, which is GatsbyJS shines. With the help of GatsbyJS we can create extremely fast static sites and it gets into Wordpress domain a lot with it. GatsbyJS also has a huge ecosystem of plugins, which enhances its functionalities. React Testing Unit testing is a very important part of ReactJS projects, especially the ones which are very large. Unit testing ensures that we have lower bugs in Production build. The two popular libraries are – Enzyme and Jest. 2. Angular It is a complete framework and unlike React requires very few external dependencies. Everything is built within Angular and we don’t have to go outside for more features. Since it was among the earliest frameworks, older projects are in Angular and it is still widely used in enterprises. A good tutorial to learn Angular is below. 3. Vue Vue is another very popular JavaScript library, which has the best features of both ReactJS and Angular and has become very popular in recent years. It is widely used in both enterprise and startups. A good tutorial to start with Vue is below. 4. NuxtJS It is used for Server-Side Rendering in Vue projects and is similar to the NextJS framework used in ReactJS for SSR.  5. Svelte It is the newest of all frameworks/libraries and has become quite popular, but still not used much in enterprises and startups. It is different from React, Vue and Angular and converts the app at build time rather than at run time as in the other three. Good tutorials to start with Svelte are below. CSS Deep DiveA lot has changed in CSS after it included CSS Grid and Flexbox; it has become much easier for developers to work with. CSS Essentials It is now mandatory for frontend developers to learn CSS Grid and Flexbox, because through it we can develop beautiful layouts with ease. More companies are moving away from CSS Frameworks and have started working with CSS Grid and Flexbox, which are now supported by all browsers. Good tutorials to learn Flexbox and CSS Grid are below. Preprocessors CSS preprocessors are used to add special functionalities in CSS, which it lacks. 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 - JavaScript 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 - Python 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 - C# 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 - Go 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 - PostgreSQL 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 - Oracle 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 - MS-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 - 2. 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 - It 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-Cassandra 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 - 3. 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 - StorageStoring 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 -2. 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. Top 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 by KnowledgeHut are appended below-CSS3JavaScriptReactJSNodeJSDevopsConclusion 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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