Node.js Interview Questions and Answer for freshers set 3
Categories: Interview questions and answers Freshers Node JS
Node.js Interview Questions and Answer for freshers (set3)
Q1. What is the framework that is used majorly in Node.js today?
Answer: Node.js has multiple frameworks, namely:
- Hapi.js
- Express.js
- Sails.js
- Meteor.js
- Derby.js
- Adonis.js
Among these, the most used framework is Express.js for its ability to provide good scalability, flexibility, and minimalism.
Q2. What are the security implementations that are present in Node.js?
Answer: Following are the important implementations for security:
- Error handling protocols
- Authentication pipelines
Q3. What is the meaning of a test pyramid?
Answer: A test pyramid is a methodology that is used to denote the number of test cases executed in unit testing, integration testing, and combined testing (in that order). This is maintained to ensure that an ample number of test cases are executed for the end-to-end development of a project.
Q4. What is Libuv?
Answer: Libuv is a widely used library present in Node.js. It is used to complement the asynchronous I/O functionality of Node.js. It was developed in-house and used alongside systems such as Luvit, Julia, and more.
Following are some of the features of Libuv:
- File system event handling
- Child forking and handling
- Asynchronous UDP and TCP sockets
- Asynchronous file handling and operations
Q5. Why does Google use the V8 engine for Node.js?
Answer: Google makes use of the V8 engine because it can easily convert JavaScript into a low-level language. This is done to provide high performance during the execution of an application and also to provide users with real-time abilities to work with the application.
Q6. What is the use of middleware in Node.js?
Answer: A middleware is a simple function that has the ability to handle incoming requests and outbound response objects. Middleware is used primarily for the following tasks:
- Execution of code (of any type)
- Updating request and response objects
- Completion request-response once iterations
- Calling the next middleware
Q7. What are global objects in Node.js?
Answer: Global objects are objects with a scope that is accessible across all of the modules of the Node.js application. There will not be any need to include the objects in every module. One of the objects is declared as global. So, this is done to provide any functions, strings, or objects access across the application.
Q8. Why is assert used in Node.js?
Answer: Assert is used to explicitly write test cases to verify the working of a piece of code. The following code snippet denotes the usage of assert:
var assert = require('assert');
function add(x, y) {
return x + y;
}
var result = add(3,5);
assert( result === 8, 'three summed with five is eight');
Q9. What are stubs in Node.js?
Answer: Stubs are simply functions that are used to assess and analyze individual component behavior. When running test cases, stubs are useful in providing the details of the functions executed.
Q10. How is a test pyramid implemented using the HTML API in Node.js?
Answer: Test pyramids are implemented by defining the HTML API. This is done using the following:
- A higher number of unit test cases
- A smaller number of integration test methods
- A fewer number of HTTP endpoint test cases