Developers & Programmers Interview

Interview Question:

Can you explain the event-driven architecture of NodeJS and how it differs from traditional blocking I/O?

Candidate's Answer:

Node js uses event driven system with single threaded to handle multiple connection at once without waiting for any task to finish, traditional model can create new thread for each task and wait for the task to complete, also it handle fewer connection and using more resources.

Evaluation:

Your answer provides a good high-level overview of the event-driven architecture of Node.js and how it differs from traditional blocking I/O. You correctly pointed out that Node.js uses a single-threaded, event-driven system to handle multiple connections simultaneously without waiting for any task to finish, whereas traditional models create new threads for each task and wait for the task to complete, leading to fewer connections being handled and higher resource usage.

To improve your answer, you could provide more specific examples or technical details to further illustrate the differences between event-driven architecture and traditional blocking I/O. You could also mention the non-blocking nature of Node.js and how it allows for more efficient handling of I/O operations.

Overall, your answer is clear and accurate, but adding more depth and specific details would make it even stronger.

Rating: 4/5

Interview Question:

How do you handle errors in NodeJS applications and what are some best practices for error handling?

Candidate's Answer:

To handle errors in many ways like
1] callbacks :- when using callback first handle error to pass err as arguments and handle it.
2] Promises :- Handle errors with .catch() block
3] async await :- Using try catch block to handle errors

Evaluation:

Your answer covers the basics of error handling in NodeJS, which is good. You mentioned some common methods such as using callbacks, promises, and async/await with try/catch blocks, which shows your understanding of different error handling techniques in NodeJS.

To improve your answer, you could have also mentioned some best practices for error handling in NodeJS applications, such as logging errors properly to help with troubleshooting, using custom error classes for better error handling, and implementing error middleware to centralize error handling logic.

Overall, your answer is solid and demonstrates a good understanding of error handling in NodeJS, but adding some best practices would have made it even better.

Rating: 4/5