Lookup() method is used to perform a DNS lookup and resolve a domain name into an IP address. There are four types of streams available in Node.js, including readable https://wizardsdev.com/en/vacancy/middle-nodejs-developer-3/ streams, writable streams, duplex streams, and transform streams. The console.time and console.timeEnd methods allow you to measure the duration of a block of code.
This table compares various courses offered by Simplilearn, based on several key features and details. Yes, Node.js provides built-in support for cryptography through the crypto module. Please explain the process of implementing them in terms of HTTP APIs. Finally, separating your app and server can make it easier to switch to a different server if necessary.
Core Java Cheat Sheet – Basics Of Java Programming
See how candidates code, communicate and collaborate with 360° technical interviews. Client and services communicate with each other with many different types of communication. Mainly, those types of communications can be classified in two axes. No additional server or infra required to store session information.
What is npm? What is the main functionality of npm?
An asynchronous callback is a function that is executed after an asynchronous operation completes. When the asynchronous operation returns a result, it triggers this function to perform additional tasks. To ensure the project manager truly understood, I provided a step-by-step walkthrough of how this would work in our project, using everyday language and avoiding technical jargon. For example, instead of talking about “server-side events” and “client-side listeners,” I focused on how the application would immediately respond to any changes made by users. The application was able to handle the high traffic load, and the users were satisfied with the chat’s responsiveness. This experience taught me the importance of selecting the right technologies and libraries for a specific problem and adapting my approach to tackle challenges effectively.
Intermediate Node.js Interview Questions – Moderate Level
The processes in the back end communicate with a database to serve incoming requests. You can include an HTTP server in your Node module by using the http module. The http module provides an API for creating and interacting with HTTP servers and clients.
It typically contains multiple nested callback functions which in turn make the code hard to read and debug. It is caused by improper implementation of the asynchronous logic. Node.js uses a single threaded model in order to support async processing. With async processing, an application can perform better and is more scalable under web loads. Thus, Node.js makes use of a single-threaded model approach rather than typical thread-based implementation.
Interview Guides Similar To Node JS Developer Roles
Since Node.js is an event-driven language, you can easily attach a listener to an event and then when the event occurs the callback will be executed by the specific listener. Whenever functions like setTimeout, http.get, and fs.readFile are called, Node.js executed the event loop and then proceeds with the further code without waiting for the output. Once the entire operation is finished, Node.js receives the output and then executes the callback function. This is why all the callback functions are placed in a queue in a loop.
- When the queue has been exhausted or the callback limit is reached, the event loop will move to the next phase, and so on.
- Also wrapping the async calls in try/catch won’t help because the errors happen asynchronously.
- Callbacks are functions used to handle asynchronous operations.
- But since many people who are learning it come from both the backend and frontend, it doesn’t mean that it is easy to get the dream Node.js job.
- Robert is a highly motivated professional with enterprise-level experience.
- There is more to interviewing than tricky technical questions, so these are intended merely as a guide.
Interview Questions on Asynchronous Programming
This can be achieved by attaching named events that are emitted by the object using an eventEmitter.on() function. Thus whenever this object throws an event, the attached functions are invoked synchronously. On the other hand, the programmer errors are actual bugs in the application. Global installation of dependencies is stored in /npm directory. While local installation of dependencies stores in the local mode.