How Axios works

axios.get('https://jsonplaceholder.typicode.com/posts')
  .then(function (response) { console.log(response.data);
  })
  .catch(function (error) { console.log(error);
  });

axios.get('https://jsonplaceholder.typicode.com/posts')
  .then(function (response) { console.log(response.data);
  })
  .catch(function (error) { console.log(error);
  });

Performing a POST request with Axios

To perform a POST request with Axios, we need to use the axios.post() method. This method accepts two parameters: the URL of the resource we want to send data to and an object containing the data to be sent.

axios.post('https://jsonplaceholder.typicode.com/posts', { title: 'Post Title', body: 'Post Content', userId: 1
  })
  .then(function (response) { console.log(response.data);
  })
  .catch(function (error) { console.log(error);
  });

In this example, we are sending a new post to the JSONPlaceholder API. When the request is successfully completed, the then() function is called and prints the received data in the browser console.

Handling errors with Axios

It is important to handle errors when making HTTP requests. To do so, we can use the catch() method. This method is called when the request fails for some reason.

axios.get('https://jsonplaceholder.typicode.com/posts/invalid-url')
  .then(function (response) { console.log(response.data);
  })
  .catch(function (error) { console.log(error);
  });

In this example, we are trying to access a non-existent resource on JSONPlaceholder. The request will fail and the catch() function will be called to handle the error.

• Using these simple methods, you can make HTTP requests easily and effectively using Axios.
• Always remember to handle errors to ensure that your applications are robust and reliable.

Handling errors with Axios

Error handling is an important aspect of using any network library, and Axios is no exception. The good news is that Axios simplifies error handling by providing a number of options for handling them effectively.

Request and response interceptors

One of the most common ways to handle errors with Axios is to use request and response interceptors. Interceptors are functions that are executed before a request is sent or after a response is received.

To add a request interceptor, you can use the axios.interceptors.request.use() method. This method accepts a function that will be executed before the request is sent:

• config: the request configuration object
• error: the error generated during request creation

axios.interceptors.request.use(function (config) { // Do something before sending the request return config;
}, function (error) { // Handle the error generated during request creation return Promise.reject(error);
});

Instead, to add a response interceptor, you can use the axios.interceptors.response.use() method. This method accepts two functions:

• response: the response received from the server
• error: the error generated during the response reception

axios.interceptors.response.use(function (response) { // Do something after receiving the response return response;
}, function (error) { // Handle the error generated during the response reception return Promise.reject(error);
});

Global Error Handling

In addition to request and response interceptors, Axios also provides a way to handle errors globally using the method axios.onError(). This method accepts a function that will be executed every time an error occurs during a request:

axios.onError(function (error) { // Handle the error globally
});

It is important to note that if you use both request and response interceptors and global error handling, the latter will only be executed if all previous interceptors have been passed.

Axios vs. Other HTTP Request Libraries

When it comes to making HTTP requests in JavaScript, there are many libraries to choose from. However, Axios has become one of the most popular choices among web developers thanks to its ease of use and flexibility.

But how does Axios compare to other HTTP request libraries like Fetch and jQuery.ajax?

Fetch

Fetch was introduced with the arrival of ES6 and is now available in all modern browsers. It is built into the JavaScript language, which means that no external library needs to be installed to use it.

However, Fetch syntax can be a bit verbose and difficult to read. For example:

• fetch('https://api.example.com/data')
• .then(response => response.json())
• .then(data => console.log(data))
• .catch(error => console.error(error))

In addition, Fetch does not automatically support JSON data conversion or HTTP error handling.

jQuery.ajax

jQuery.ajax is one of the oldest and most familiar libraries for HTTP requests in JavaScript. It has a very simple syntax to use:

• $.ajax({ url: 'https://api.example.com/data' })
• .done(data => console.log(data))
• .fail(error => console.error(error))

However, jQuery.ajax requires the jQuery library to work and does not natively support JSON data conversion.

Axios

Axios has a very simple syntax and is easy to use. For example:

• axios.get('https://api.example.com/data')
• .then(response => console.log(response.data))
• .catch(error => console.error(error))

In addition, Axios natively supports JSON data conversion and HTTP error handling. It is also possible to easily configure requests with options such as query parameters and custom headers.

For these reasons, Axios has become one of the most popular libraries for HTTP requests in JavaScript.

Conclusion

In conclusion, Axios is a great choice for making HTTP requests in JavaScript thanks to its ease of use, flexibility, and numerous features. Although there are other libraries available such as Fetch and jQuery.ajax, Axios offers a simple and elegant syntax and natively supports data conversion to JSON and handling of HTTP errors.

If you are a web developer looking to simplify the process of making HTTP requests in your project, Axios could be the perfect solution for you.