20 Server-side Interview Questions and Answers

Server-side programming is a vital skill for any web developer. In a server-side programming language, code is executed on the server rather than the client, meaning that the client only needs to load the final output of the code. This can be contrasted with client-side programming languages, such as HTML and CSS, which are executed on the client-side (the user’s web browser).

If you’re applying for a position that involves server-side programming, you can expect to be asked questions about your experience and skills. In this article, we review some common server-side programming questions and provide guidance on how to answer them.

Server-side Interview Questions and Answers

Here are 20 commonly asked Server-side interview questions and answers to prepare you for your interview:

1. What do you understand by the term ‘server-side’?

Server-side refers to the side of a client-server architecture that is responsible for handling the back-end processing. This includes tasks such as database interactions, application logic, and user authentication. The server-side is typically written in a server-side scripting language like PHP, Ruby on Rails, or ASP.NET.

2. Can you explain what server-side scripting is?

Server-side scripting is a type of programming that is executed on the server rather than in the user’s browser. This means that the server will do all of the heavy lifting when it comes to running the script, and the user’s browser will simply display the results. This can be contrasted with client-side scripting, which is executed in the user’s browser.

3. Is there a difference between client-side and server-side validation of forms? If yes, then what are they?

Client-side validation of forms is done entirely on the client’s computer, without any communication with the server. Server-side validation, on the other hand, involves the server checking the form data before it is processed. This can be more reliable, but can also be slower and more resource-intensive.

4. How can you create a server-side session in PHP?

You can create a server-side session in PHP using the session_start() function. This function will create a session and store it on the server.

5. What’s the best way to access form data sent from a client to a server using GET or POST methods?

There are a few different ways to access form data sent from a client to a server using GET or POST methods. One way is to use the $_GET or $_POST superglobals, which are arrays that contain all of the data sent via the GET or POST methods, respectively. Another way is to use the php://input stream, which can be used to read raw data from the request body.

6. Why would you choose to use server-side processing over client-side processing for your next project?

Server-side processing has a few advantages over client-side processing. First, server-side processing can be more secure since the data is not exposed to the client. Second, server-side processing can be more efficient since the server can optimize the processing of the data. Finally, server-side processing can be more scalable since the server can handle more requests than the client.

7. How does AJAX help improve the performance of web applications?

AJAX helps improve the performance of web applications by allowing for asynchronous communication between the web browser and the web server. This means that the web browser can request data from the web server without having to reload the entire page. This can help improve the performance of web applications by reducing the amount of data that needs to be transferred between the web browser and the web server.

8. How does Server Sent Events (SSE) differ from Web Sockets? Which one would you recommend for building real-time apps?

Server Sent Events (SSE) is a technology for delivering push notifications from a server to a web application. It is a one-way communication protocol, meaning that the server can send messages to the client, but the client cannot send messages back to the server. Web Sockets, on the other hand, is a two-way communication protocol, meaning that both the server and the client can send messages to each other.

I would recommend using Web Sockets for building real-time apps, as it provides a more robust communication channel than SSE.

9. What are some differences between NodeJS and ASP.NET MVC?

NodeJS is a JavaScript runtime environment that is used for developing server-side applications. ASP.NET MVC is a framework for building web applications that can run on a web server. Both can be used to develop web applications, but NodeJS is typically used for developing applications that are more lightweight and require less resources, while ASP.NET MVC is better suited for developing more complex applications.

10. Can you explain how HTTPS works?

HTTPS is a secure communications protocol that is typically used to protect sensitive information from being intercepted by third parties. When you connect to a website using HTTPS, your browser will first establish a secure connection with the server. Once the connection is established, your browser will send a request to the server for the desired information. The server will then send the information back to your browser, encrypted so that it cannot be read by anyone except for your browser.

11. What security issues should you be aware of while working with server-side code?

There are a few key security issues to be aware of when working with server-side code. First, you need to be careful about how you handle user input, as it can be easy for malicious users to inject code that can wreak havoc on your server. Second, you need to be careful about what information you store on the server, as it can be easy for hackers to gain access to it. Finally, you need to be careful about the permissions you give to users, as they can use them to gain access to parts of the server that they should not have access to.

12. Can you give me an example of a time when you used cookies as part of a server-side solution?

A common use case for cookies on the server side is to keep track of user sessions. For example, when a user logs into a website, the server can set a cookie containing a session ID. The server can then use this session ID to look up the user’s information on subsequent requests. This allows the server to keep track of which user is making which request, even if the user is not explicitly logged in.

13. In which situations will you prefer to use session storage over local storage?

Session storage is generally preferred over local storage for server-side applications because it is more secure. With session storage, the data is only stored temporarily and is automatically deleted when the session ends. Local storage, on the other hand, stores the data permanently, even if the user clears their cookies. This makes local storage less secure and less private, which is why it is not generally used for server-side applications.

14. What is the purpose of Cross Origin Resource Sharing (CORS)?

CORS is a mechanism that allows restricted resources on a web page to be requested from another domain outside the domain from which the first resource was served.

15. Can you give me an example of a time when you used JSONP instead of CORS?

CORS is a standard that allows for cross-origin requests, while JSONP is a technique that allows for cross-origin requests. JSONP is generally used when CORS is not available or when it is not possible to use CORS.

16. What is the role of Object Relational Mapping (ORM) in server-side development?

ORM is a technique that allows developers to work with databases using objects instead of SQL queries. This can make development more efficient and can also help to reduce the amount of code that needs to be written.

17. When developing server-side JavaScript applications, why is it important to consider possible injection attacks?

Injection attacks are a type of attack where malicious code is injected into an application in order to exploit a vulnerability. This can be a serious issue when developing server-side JavaScript applications, as the code that is injected can potentially gain access to sensitive information or perform other malicious actions. In order to protect against injection attacks, it is important to validate all user input and escape any potentially dangerous characters.

18. What are some advantages of using server-side rendering for frontend development?

Some advantages of using server-side rendering for frontend development include:

– Reduced load times: Server-side rendering can result in faster initial load times for a website or application, as the HTML is already generated on the server and does not need to be generated on the client-side.

– Improved SEO: Server-side rendering can also be beneficial for SEO, as search engines are able to index the HTML of a website or application more easily when it is generated on the server.

– Enhanced user experience: Server-side rendering can provide a smoother user experience, as the HTML is generated before the user even begins interacting with the website or application.

19. What are the pros and cons of using a single page application framework like AngularJS on the server side?

The main advantage of using a single page application framework like AngularJS on the server side is that it can make your application more responsive and faster. The downside is that it can be more difficult to debug and test, and it can also make your application more vulnerable to security risks.

20. What are some common pitfalls that developers run into when writing server-side code?

A few common pitfalls that developers run into when writing server-side code include:

– Not properly handling errors and exceptions
– Not properly validating user input
– Not properly sanitizing user input
– Not properly securing sensitive data
– Not properly scaling the code to handle increased traffic