20 Axios Interview Questions and Answers

Axios is a promise-based HTTP client that works in the browser and Node.js. It provides a simple and clean API for making HTTP requests. In this article, we will discuss some commonly asked questions about Axios and how you can answer them.

Axios Interview Questions and Answers

Here are 20 commonly asked Axios interview questions and answers to prepare you for your interview:

1. What is Axios?

Axios is a promise-based HTTP client for making asynchronous HTTP requests. It works in the browser and in Node.js.

2. Can you explain what Axios does with a simple example?

Axios is a promise-based HTTP client for JavaScript which can be used in the browser and in Node.js. It makes it easy to send asynchronous HTTP requests to REST endpoints and perform CRUD operations. For example, you can use Axios to fetch data from a REST API, submit form data to a REST API, or make a simple HTTP GET or POST request to a REST API.

3. Is it necessary to use promises when using Axios? If yes, then why?

Yes, it is necessary to use promises when using Axios. This is because Axios is built on top of the promise API, and so it uses promises to handle all of its asynchronous requests.

4. How do you handle errors when using Axios?

When using Axios, you can use the .catch() method to catch and handle errors. This is similar to how you would use a try/catch block when using other programming languages.

5. What’s the difference between GET and POST requests in Axios?

The main difference between GET and POST requests in Axios is that GET requests are used to fetch data from a server, while POST requests are used to submit data to a server. GET requests are typically used when you just want to retrieve some data from a server, while POST requests are used when you want to submit data to a server (for example, when filling out a form).

6. What are some examples of Get requests that can be made using Axios?

Get requests are used to retrieve data from a server. Some examples of get requests that can be made using Axios include retrieving a list of users, retrieving a list of posts, and retrieving a list of comments.

7. What are some examples of Post requests that can be made using Axios?

Some examples of Post requests that can be made using Axios include creating new data in a database, submitting a form, and uploading a file.

8. What happens if an error occurs while making post or get requests using Axios?

If an error occurs while making post or get requests using Axios, then the request will be automatically rejected and an error message will be displayed.

9. What are some examples of Delete requests that can be made using Axios?

Some examples of Delete requests that can be made using Axios include:

-Deleting a specific resource by id
-Deleting all resources that match a certain criteria
-Deleting a resource that is no longer needed

10. What are some examples of Head requests that can be made using Axios?

Head requests can be made for a variety of reasons, but some common examples include checking to see if a page exists before making a GET request, or checking to see if a user is logged in before allowing them to access certain content.

11. How do you make put requests using Axios?

You can make put requests using Axios by using the axios.put() method. This method takes in the URL of the resource you want to update as well as the data you want to send in the body of the request.

12. How do you upload files using Axios?

You can upload files with Axios by passing the file as a parameter in the post request.

13. What are some advantages of using Axios over other HTTP libraries like jQuery AJAX?

Axios is a promise-based HTTP library that provides a simpler, cleaner interface for making AJAX requests. It also has a number of other advantages over jQuery AJAX, including automatic transforms for JSON data, support for cancelling requests, and built-in support for progress tracking.

14. What are some important features of Axios?

Some important features of Axios include its ability to make HTTP requests from within the browser, its support for Promises, and its interceptor feature, which allows for easy handling of errors.

15. Can you tell me more about the core concepts used by Axios?

Axios is based on a few core concepts:

– Promise: Axios uses promises to handle asynchronous requests.
– Interceptors: Axios has a feature called interceptors that allows you to intercept requests and responses before they are handled by the then() or catch() methods.
– Axios Instance: An Axios instance is a pre-configured instance of Axios that can be used to make requests.

16. How is Axios different from Fetch API?

Axios is a promise-based HTTP client that works both in the browser and in the node.js environment. It provides a simple and clean API for making HTTP requests, and it supports a wide range of features, including interceptors, automatic transforms, and error handling. The Fetch API, on the other hand, is a browser-based API that provides a simpler interface for making HTTP requests.

17. How is Axios different from SuperAgent?

Both Axios and SuperAgent are libraries used for making HTTP requests, but they have some key differences. SuperAgent is a library that uses a more traditional callback-based API, while Axios uses a promise-based API. This means that with Axios, you can use async/await to more easily handle asynchronous requests, while with SuperAgent you will need to use callbacks. Another difference is that Axios automatically transforms the response data into JSON, while with SuperAgent you will need to do this manually.

18. How is Axios different from jQuery Ajax?

Axios is a promise-based HTTP client that works both in the browser and in Node.js. It provides a simple and clean API for making HTTP requests. jQuery Ajax is a library that provides a simpler way to make Ajax requests.

19. Are there any disadvantages of using Axios? If so, then can you give me some examples?

While Axios is generally seen as a positive tool, there are a few potential disadvantages to using it. One is that Axios is not always compatible with older browsers. Another potential issue is that Axios can sometimes be slower than other tools because it relies on promises, which can take a bit longer to resolve.

20. What are some alternatives to Axios?

There are a few alternatives to Axios that are popular among developers, including:

– fetch: This is a built-in browser API that allows you to make network requests.
– superagent: This is a lightweight HTTP library that includes a number of features not found in fetch, such as a request queue.
– request: This is a popular HTTP library that has a wide range of features, making it suitable for use in a variety of situations.